Here’s the list of products reviewed. More details in the video description. Thank you! Beyondlife: amzn.to/440PxbG RXXXWELD: amzn.to/3DQy5ft OIMERRY: amzn.to/3qkKdCh JOUNJIP: amzn.to/445DE43 Allturn: amzn.to/44eeIYw Ryobi Hot Glue Gun: amzn.to/3YyYXtC J-B Weld Plastic Bonder: amzn.to/3s6s77B J-B Weld Original: amzn.to/3KAp3qo
I'm sure you knew this, but, the ideal repair method for those comparison slices you made would be to slice a pair of ~45° cuts that intersect the slice at the back so that the plastic, so that the hot plastic 'stitches' the slice shut. After which, you sand it to make it look good. That is under the presumed objective that this not only to seal it, but to make it look undamaged.
As an automotive technician I use the jounjip kit and found that for best results melt the wire mesh into the plastic before using the filler. Often times it’s stronger than the original piece and has saved my butt countless times. There is a learning curve and results become stronger and look better with practice.
You beat me to it. I said the same thing in my comment. It's a bit of a learning curve, but once you get it right, the repair is often stronger than the original piece. It's best to heat the mesh directly to melt into the original plastic then use the filler.
I really appreciate you deciding to do a video on plastic welders and hot staplers as I've used both for several years, and was excited to see this one come out. Unfortunately, the processes used in the video were all wrong and completely invalidated the tests. Most of the principles used in metal welding apply here too. 1. You should make a small bevel at the junction of the 2 pieces, on all sides to be welded. 2. The plastic representing the base and the plastic representing the filler should both be melted and mixed together. 3. You can buy different types of filler rods online. The plastic used as filler needs to be the same as the base plastic. 4. The wire screen is supposed to be completely embedded into the base plastic. Not just "glued" on top using filler. 5. When inserting the staples into the base plastic, you should end with a slight twist to completely embed the staple and cover the entrance grooves. Would love to see a redo of this video if you decide it's appropriate. Thank you.
His video pretty much showed how most uniformed DIY guys would proceed. Can you recommend a video or source that goes in to detail for maximum efficiency? Thanks.
I hope he revisits. There’s always great comments on PF’s videos but this one has some top notch ones. I really wish I had the time to sit here and read them all!
Thanks for being the most thorough and honest reviewer out there. Your lack of taking sponsors helps you stay unbiased. Thats why we all love your content. Keep it up!
For those who don't know what HDPE means, it means high density poly-ethylene, and is manufactured differently than is Poly-ethylene. HDPE is typically used for fuel tanks, and fuel and oil containers in consumer goods. For one that is desperate to fix a plastic gas tank, cutting an oil container into strips the color of the tank, as this is the same plastic in both. I repaired a generator gas tank this way, and used a 100w soldering gun. It was leak proof, and was tested by two different mechanics, and they both approved. For white plastic repairs, isopropyl alcohol bottles are HDPE, and work just as well.
Milk jugs are also HDPE. Look for the triangle with a 4 in the middle. There are many videos of making really cool things via melting milk jugs in the oven and using the block of plastic. It's a very interesting rabbit hole to go down.
I've done quiet a bit of plastic welding at a previous job and one flaw in this test I noticed is you're using dissimilar materials. For instance, if you're work piece is polyethylene you need to use a a PE filler rod and if it's polypropylene you need to use a PP filter rod. Using PE filler rod on abs you will never get it to bond and make a strong weld. Just a bit of advice if you ever do another plastic welding video, make sure to get filter rods of the same family as the work pieces to get professional results. I do like how you compared hot glue and JB welds.
@@rc-t3k if I'm understanding your question correctly it doesn't matter as long as you can melt the material and filler rod slightly to get everything to bound together.
I work in the plastic dam lining industry. Plastic (particularly HDPE) oxidises quite rapidly, we what we do is use an angle grinder with a flap disk to scuff away that layer before doing any extrusion welding as it makes the bond much stronger. Also, for butt joins you need to fillet/v-groove the edges to increase the surface area, and also ensure all contact points are at melting temp so the new material can become part of the old. P.S. If your hot air gun is melting holes in stuff, turn it down - It's too hot! Just like MIG.
Absolutely right about the need for fillet in butt welds. 45 years ago we used hot air guns on PVC sheet that had a feed hole for PVC filler rod. We used a hand held "Scarcen Scraper" to cut the v shaped grooves immediately prior to welding, and isopropyl alcohol to clean the sheets. Probably not a good thing to breathe up, nor were the shredded fibreglass particles we breathed up from the adjacent workshop.
I have some cracks in HDPE totes (Rubbermaid Roughneck). I had a hard time trying to get undamaged totes in the 50 gal so I decided to try plastic welding instead of play the return game (in hindsight I should have just ordered 3-4 and play mix and match since their shipping packaging is terrible). If I want to attempt a HDPE weld of some hairline cracks, what's the best method to try to weld these? I don't want to fill totes with weight and then cause more cracking. I plan to practice on milk jugs to see if I can get a method to work, but any hints would be nice. Can I tape a non-stick material like teflon and then use a heat gun and apply pressure to the area, then let it cool and peel the teflon off? I also have the Jounjip and could try to weld plastic from milk jugs since they seems to both be HDPE.
I've done a lot of plastic welding on airline luggage pods. The welder I used is similar to the Beyond Life type which has a preheating air jet. They work extremely well. The trick is to let the hot air do the work, and then force the rod into the molten plastic. It's about technique. For something as thick as your test pieces, you need to make V-cuts into the ends and then weld both sides. It would be very strong if done that way.
Having worked at two machine shops that employed in-house plastic welders, I concur withe the use of the Beyond Life type welder. There were two types of tips I saw frequently used, one was like a 1" hot knife that they would run along the bottom of the chamfers to tack the parts together. The second tip was like the one shown where the filler rod was fed through the tip to preheat the rod and the path the rod was going to be laid in. The trick is to only heat the air/tip enough to barely melt the plastic. You want both the part and the filler rod just soft enough to use the tip to force the rod into the groove made by the mating chamfers. The finished bead should be proud of the surface.
Using a hot air jet is a fairly old method. I learned it 20+ years ago and it wasn’t new then either. Trick is to treat it more like a tig process. You are melting the substrate with the air jet then adding the rod. Keep the air jet pointed at the point where all 3 meet and slowly move across your joint. Definitely takes practice to get the speed and heat right.
I came here to say that. I used to work at a company that made plastic enclosures and we used similar style welders. There’s a learning curve that I never climbed, but with practice the bonds can be ridiculously strong.
PF added the weld before the mesh then additional weld on top. When it comes to plastic welding, I usually heat the mesh directly to melt into the original plastic before adding weld with the sticks. I've found this to be a better way of reinforcing the structural integrity.
@@NoughtSure It truly depends on the thickness of the plastic combined with the expected forces applied during active use. I'm sure something as thick as a kayak would do slightly better with the staples by themselves than it would with the mesh. This is due with the forces coming from the top down rather than lateral force. With that being said, for a kayak, I would probably do both staples and mesh due to the fact that the mesh has a wider surface area to hold against any lateral force.
One of the biggest flaws, if you ever want to revisit this, is that the plastics need to be flame/plasma treated if you’re using epoxy (JB Weld) or other adhesives on them. We use epoxy all of the time to bond to plastic parts, the ONLY way they stick is if you flame treat or plasma arc the surfaces. Sheet molders/casters may also use mold releases and those have to be completely removed/burned off for the adhesives to work. Easiest way is to just use a blow torch and barely melt the surface, it’s essential to get the epoxy to bond. We’ve had employees forgot to flame treat plastic parts before potting and the epoxy pops out like a cake in a well greased pan.
Few people know about flame treatment before adhesive bonding and its the easiest thing to do. A butane gas torch with a clear/blue flame will work. You can test the surface energy using dyne pens (>38dyne-cm should be good) or even a distilled water fog spray to see if it wets out on the surface. If you want it more fool prof you can also buy handheld corona or plasma treaters that will do the same thing, but with less risk of burning/melting. However, they are $$$!
I sorta discovered this on my own when gluing fittings into polycarbonate tubes. On some, I flame polished the machine marks from where I cut them, on others, I just sanded and cleaned with isopropyl. The ones I flame polished have such and incredible bond that I'm pretty sure it's stronger than the original material! The other ones just kind of cracked and felt like the glue never cured. I was thinking it might have had something to do with tempering some internal stresses within the polycarbonate that locked in during manufacturing, but after reading your comment, it makes so much more sense!
The thing about this video is you may not have seen that he is not using molded parts and he sanded it down before gluing so reconsider that he might be using it properly for epoxy but other parts he should have melted mesh into plastic to get best results
I tried spin welding polypropylene and the fittings kept popping off with little effort. The interface between the parts always seemed waxy. She's flame treating sound like something that could help with that defect?
Technically speaking, I am a professional plastic welder. Some tips. Hot air welders are the best, they just take a little practice. The key is looking up the proper welding temperature, for HDPE it is 560-570 F. If you are too hot it will ruin the integrity of the plastic. Use the same filler material as the base material! Different plastics do not stick to each other. The base material and the filler material should be heated/melted the same amount and allowed to cool before you move anything. You are welding, not gluing despite how it may seem. Lastly, cleanliness is very important. Instead of sanding, I suggest scraping. You need to remove the oxidized layer of plastic on top because that cannot be welded properly. Cleaning with alcohol is important too. Look up videos on proper hot air plastic welding for more info. I think Leister has helpful content available.
@@dubmob151 I was wondering the same - whether my hot-air rework station could be used as a hot-air plastic welder. My station supports temperatures between 100 to 500 celsius (212 to 932 fahrenheit) along with adjustable air flow and different size nozzles, so maybe, but I'm sure technique will make a big difference between messy failure and success.
The wire mesh should be thru-melted into the base piece being repaired and THEN have filler added to smooth. This can ONLY be done with the higher heat tools....also, when you retest using this method you should also add steel wool as this has been common for years and in pieces that really NEED to remain flexible without breaking the individual strands of steel wool seem to add a lot of flexibility without sacrificing breaking strength.....but as always GREAT FREAKING JOB!!!! One of my top 5 creators on UA-cam no doubt
I was going to suggest melting the screen in as well. It worked well while repairing a plastic ATV skid plate and I used the side edge of a box wrench to further push in the screen. The wrench cools the spot to secure it as you work the screen in.
I have been plastic welding as part of my job for 35 years and steel wool is a poor choice since it is covered with oil and would quickly rust once the oil coating is cleaned off. Stainless steel screen is all you need but if you want something like steel wool, get some s.s. shavings from a machine shop.
FYI: Not only showing us what are the best products but helps most of us who have never tried any form of the tools you show....a big THANK YOU from all of us.
In this particular instance, the "best product" can very much be situational and technique makes a big difference. When plastic welding with HDPE, PE and PP plastics ideally, you want to melt the original material back together before adding new material. If you're using staples or wire mesh, melt it into the plastic before adding new material. The new material should fill in the void left from melting the original plastic back together. This will give the best result and in most cases you have to add very little new material. If done properly, the repaired area will be as strong or stronger than it originally was.
I've been welding plastics for 10+ years now after an autobody guy showed me his methods. I've adapted it over time and have had great success with aluminum window screen mesh, 2 part epoxies, and a $20 Weller soldering iron I purchased from Home Depot 10 years ago. I've fixed several different types of equipment and haven't had any failures that weren't from user error after the repair. Never had luck with a hot glue gun when I attempted it. Great video! I always check your channel before making purchases on tools lol. Keep up the great content.
🤩 I used a JB Weld product and plastic strips from an electrical box to fix our old pool cleaner head: worked fine for two more years! Plastic welding is something I should learn, however! Thank you Todd! 😎✌️
The problem with plastic welding is knowing the exact plastic and if it's got any additives. I worked in a plant making dielectric insulators to nylon (nylatrol and other nylons) for chemical rated bushings. Some of that stuff was almost like oil-impregnated bronze but without being labeled as such. Imagine trying to weld oil impregnated bronze 😂
Awesome! I have a kayak hanging in the garage that has a crack from an encounter with a pointy rock. I have debated the JB weld vs a welder. Many years ago my father would repair his green Colman canoe with quakerstate oil bottles... used some hot melt glue and a propane torch. The smell flooded back to me as I typed. Keep up the great work. Cheers from Wisconsin!!
I have zero experience with these gadgets but we routinely repair abs plastic tabs that are broken by knucklehead mechanics using impact tools on semi truck dash parts. We use a combination of wire mesh and fiberglass mat/resin to build new tabs. These trucks see 150k miles a year of pounding on the interstate and we have never had a failure. We have found that the few times that guys have come in with DIY plastic welded repairs, the plastic around the repair is brittle from the heat of the repair tool and is the point of breakage. Great vid Todd.
I briefly worked for a company where we welded together huge research fish tanks with a plastic welder like the Beyond Life style you have here. The technique is very similar to arc welding and takes a lot of time to learn how to use well, but it did a great job of welding plastic parts together. We didn't use any metal reinforcement on our plastic tanks and they held up just fine with hundreds of gallons in them. The trick is to get the heat setting correct first and foremost, and then you have to move fairly quickly to avoid burning through. Like I said, it's just like arc welding, so you have to put some hours in to get it right.
Harbor Freight sold a tool similar to this years ago. I got one, but I haven't used it as I have nothing to test on...I knew I needed to develop technique first before using. All the stuff I have (classic motorbike plastics) is a one-shot deal...either I get it perfect on the first try or it's ruined. Sounds like I might have to take it to a professional!
For ABS, acetone welding and ABS/acetone slurry have never let me down. Sometimes it takes a very long time for the acetone to evaporate out if the slurry is put on very thick.
When doing plastic repairs in the past I have used a soldering iron, I find that works well enough for me considering its very rare that I repair plastic. Thanks for another great video as always :D
Plastic welders are cool, but I'd really love to see you test budget multimeters. You can probably use a fluke as a control to compare the budget multimeters one feature at a time, ohm's, volts, amps etc.
Having used countless multimeters over the decades, I've found even the cheapest have reasonable tolerances and provide good results.What they don't have (and which would be difficult to test), is the ability to withstand the test of time. My Fluke is ancient and could use a fresh set of sockets. All the cheap stuff was binned years ago.
I have tried several small multimeters looking for one that would take up less space than. a Fluke 179. The most frequently evident shortcoming of the less expensive meters is how long they make you wait before they settle in on a reading. The two I ended up carrying are the tiny Fluke 107 and the Hioki pen meter. Other than its larger size, the annoying thing about the tiny Fluke is the lack of probe clips on the case. Of course, the safety category should be the highest priority consideration, but it's hard to want to test whether they're lying on that score.
I think you need to revisit this one ASAP. I thought that the Polyvance plastic welder was the model that most people that were serious about plastic repair bought. I’m disappointed that this wasn’t added to the line for testing. Another point I’d like to add is that (Like with most things) technic is key and was lacking a little bit. I just want to see a fair shakedown. As always, Thank you for your Time and Dedication to making these unbiased videos! It’s greatly appreciated.
I think most people are going to do this type of repair one or twice in their lifetime. So doing these tests without having any experience or practiced skill with each system is a real world example to base your choice on.
@@troyreed7942 Exactly. People aren't going to become expert welders before they do something like this, not at this point in time anyway. I found this very real world and great for the average DIYer.
@@troyreed7942while what you say is true, the title of the video is "best blastic welder" not "easiest plastic welder for beginners" As is typical with this channel, a lot of care is out into the testing process, and unfortunately this product requires a lot of technique to get proper results. Either the title of the video should change, or it should be revisited and updated!
I’d be interested in seeing the PolyVance tested as well. You do a great job testing, but with almost 3M subs, it isn’t surprising a few people have something to add.
I always appreciate your video's! I do have to say that there seem to be some glaring problems with this test and I'd suggest if you do it again you try some of the following. 1: Use a soldering iron with a fairly small tip, maybe between 1/16" - 1/8" and press it down through the plastic between the crack/break. Then either do a stir weld technique (spinning the iron or piece) or make small circles and move along the crack as it melts. I usually melt about 2x the width of the soldering tip. I've even used the tip of a hot glue gun if it gets hot enough 2: you need complete penetration of the heat on both sides of the plastic. If it is thick plastic I suggest warming the area (about 1-2" on either side of the crack/break) some how. A heat gun, hair dryer, hair straightener (ironer/flattener), toaster, toaster oven, torch (be careful & don't get too close). The warmed plastic melts much easier & kind of tempers the weld line and it seems to be less brittle 3: Use filler plastic of the same type. Identify the plastic by the recycle number (1-7 I think). Most 5gal buckets are HDPE and I use one of these for filler/patch material. Just cut strips to different widths. It's really nice to have some very thin ones to be able to feed it into tight areas. 4: Apply the staples after making the weld described above. Apply a top layer of plastic if desired. I'm sure you can make staples from any metal, even normal wood or cardboard staples (heavy duty shipping staples that so love to slice people open). Just bend to shape & heat with a torch. You can bond 2 layers/sheets of plastic together (on top of each other) at the edges by using a thin soldering iron tip about the same diameter as a single layer of plastic is thick. Do the spin weld or small circles with the tip inserted as far as possible along the edge.
Been doing steps 1 and 3 with a cheap, chisel-tip soldering iron for a year and it works great, especially on cracks. And is neater than most of the demonstrated techniques.
This is great stuff. I have fiddled with plastic welding just enough to know its insanely complicated. Much like metal welding, you need the appropriate filler rod. Can't use ABS rods on PC base material or such. Prep is key too, I repaired a HDPE tank for a boat lift, and I had to carve out the crack to get some good penetration and actually stick the new filler plastic to the old plastic. Ended up holding up great for a long time, but the learning curve was a challenge. Thanks so much for making a great video!
The beyond life welder requires a lot of practice and technique to use right but way more versatile. We use that style of welder for vinyl floor welding in hospitals in surgical rooms. You can't use any of the other style welder in situations like that Id recommend looking up vinyl floor heat welding. It should give you a good idea for how to make a good hot air weld. Nowadays even if I do not have a hot air gun, If I need to weld plastics I will melt both the base material and the filler rod right at the Joint area to get a very good repair. Similar to tig welding
@@kittytrailI install welded vinyl flooring and I like Steinel heat guns. They're a lower price than the Leister guns but seem to be of similar quality. I think the Steinel guns are made more for flooring so they don't have to be as powerful as the Leisters that are more designed for roofing. I know on my Steinel I can weld floors with the heat and fan all the way up but if I try that with a Leister I'm scorching the vinyl unless I'm moving fast and perfectly smooth. And that's with a good Turbo brand speed welding nozzle on both guns.
@@ProjectFarmBetter quality versions of that tool have independently adjustable controls for heat and fan speed. I also believe the Chinese knock off versions use weaker heating elements with a duty cycle that causes fluctuations in air temperature. It's the kind of thing where the quality of the tool makes as much difference as the skill of the operator. Don't beat yourself up, there's a steep learning curve and using cheap tools is a handicap by itself.
@@simpsonryan32I have two types of Steinel heat guns, the traditional gun shaped, and the inline style I bought specifically for plastic welding. Where can I buy one of those Turbo tips you spoke of? I only have narrow, wide, and heat shrink nozzles.
@@simpsonryan32 yep, the Steinel ones are fine too and they also make quality heat guns for lots of other brands too. 😉👌 still preferring, for my work, them Leisters as they can run for hours without much temp variations in the output. 😽
I appreciate the video. I was planning on ordering one of the Allturns for installing the staples to help strengthen the welds that I occasionally need to do and this seems to confirm that it will help. I have just been getting by with a soldering iron while doing these repairs. When I do a repair, I first clean the plastic with soap and water and then rub it down with rubbing alcohol. I then stitch the existing plastic together with the tip of the soldering iron going perpendicular to the crack. This holds the pieces together while I'm working on it. I then go back over it with the tip angled down at a 45 degree angle to create a V pocket into the crack. This gives me a pretty good weld with the existing plastics. I then melt additional plastic to the V pocket and work the new plastic into the old. I'm sure I could make stronger welds if I knew how to identify what plastic I was working with and obtained the correct filler plastic but since I don't know this I just do my best. So far I haven't had a repair fail and the plastic that I typically use as a filler is the black automotive plastic that I find that at almost any intersection from traffic accidents. Most of my repairs are on plastic parts on mowers and other lawn care equipment. I only end up plastic welding once or twice a year.
Good video, I've been using a soldering gun to repair plastic for years now. Word of advice, place/clamp the wire mesh on the plastic then use the welder/iron to heat the mesh till you can press it into the plastic. Then use the plastic rods to cover the mesh so it can be sanded smooth.
Another great video! I used black zip-ties, a big flathead screwdriver, and a propane torch to fix the plastic tank on my radiator. Worked great for over a year. I would rather have had a hot iron like these, but when you have to get to work. You use what you've got.
Cheap zip ties are made from plastics with low melting points and as such are not a great choice for repairing radiators. Might be why your repair did not last forever. Radiators I think are usually made from glass reinforced high temp nylon, repairing them with the same material would give the best result.
@infernaldaedra an emergency repair .eant to get you to work that day, that last over a year is a win. Any plastic weld job on a radiator tank is likely to be temporary, it dirty hot and under pressure.. all repairs are short term patches in that setting..
I noticed the plastic glue sticks are much better than years ago. I had some glue from 15 years ago that is brittle and doesn't bond well, and I recently bought some sticks and they hold and glue great, much stronger and flexible.
@@elitescouter To be fair, that's also basically how Apple weatherproofed the new Airpods Pro 2, just filled the interior seams with globs of hot glue.
You do such a great job with your reviews. For plastic repair as many others have noted, there is a lot more to know to make successful and durable repairs. The first thing to know is when to give up and replace the piece rather than attempting a repair. For many plastics in commercial use, a repair will never truly be successful. The key ideas to know are these: first - know which plastics are which, and what repair techniques can and do work. For many thermoplastics that means knowing what temperature to use, what pressure, surface removal, and technique. For some, heat is not the answer, and some glues may be effective, at least temporarily. For some plastics (fluoridated polymers like Teflons) high temperatures are a no-no, and exceptionally good ventilation is required. Best is to not attempt to repair those if you do not know. At high temperatures these plastics give off highly toxic fluoridated organic compounds. These can be fatal. For beer drinkers, attempting to repair these with poor ventilation can rapidly lead to nausea, giant purple splotches, flu like symptoms and a trip to the emergency room where the doctors will be baffled. For common plastics like the olefins (polyethylene, polypropylene and copolymers of these), repair is easy. First drill a small hole right at the ends of the fracture. This terminates the break so that it doesn’t continue. Next, champfer the split so that the full thickness is exposed and oxidized polymer is removed. Next, use a rod of the same material and a heat gun to gently raise the local area to the “glass transition temperature”. This is just shy of melting. The visible properties will change slightly. It will turn “glassy”. Now gently insert the rod into the fracture and melt it along with the base material. This is similar to metal welding, but you don’t make a “puddle” or use circular motions. Gentle straight motions are fine. Just as with metals, thick cross sections may require two or more passes to fill the fracture and melt the entire surface together. The end result will be a smooth surface. It will be quite noticeable unless you have exceptional technique. Sanding and then surface flowing with mild heating can create a very nice joint. Some plastics, such as highly cross linked polyethylene or polybutylene may not successfully be repaired in this way. Others like ultra high density polyethylene may appear to be repaired, but will fail later. What happens here is that the polymers don’t truly interpenetrate. Instead the surfaces weakly join, and a fracture will reopen later as the join line splits. High density polyethylene can be successfully butt fused or be welded. But careful control of temperature and pressure is required, and a good eye is essential. If the join has a right angle or worse, it will fracture. The transition must be smooth with no distinct corners. Other plastics work similarly. Which can be successfully joined or repaired depends on a lot of factors. Knowing what plastic you are dealing with is key. And just as with metals, it is possible in some cases to seemingly join dissimilar materials, only to have them fail later. Just as you can weld monel to stainless steel in a seemingly perfect join, only to be able to shatter the weld by rapping it an hour later with a hammer. Some plastics, like PVC can be easily repaired using solvent based glues. However, it is vital to know why the plastic failed. PVC fails easily under UV exposure. It is also a “garbage” plastic with dozens to hundreds of chemical additives. Most common are phthalates. These leach out with warm caustic solutions that can redeposit into the plastic in another place. As a result, one section of pipe for example can become extremely brittle, with another section turned into something akin to rubber. Phthalates are toxic. PVC should NEVER be used in drinking water systems - despite that being allowed in many jurisdictions. Etc…
Wow! This is a really good idea for a review. I have looked into solutions for cracked parts on my dash and stumbled across these kits a few times. Much appreciated. 👍
I think you should re-do this one and give it fillets or somehow else melt the joint. From what I've done and seen others do, it helps to (if possible) get the break melted. Otherwise the only strength comes from the thin layer you applied after the damage. Since it's plastic, it's possible to melt it back to almost original.
Thanks for also providing a forum for folks with experience to give tips in the comments! I learn a lot from these videos but also from reading what everyone says after
I have the Harbor Freight model, similar to the RX Weld, but same colors as the Jounjip. The Jounjip tips will fit as replacements but you need to rethread them as they are a bit larger (and more durable). I also have the hot staple gun, just one of the $25 ones from Amazon, they're all the same. Staples are universally sized. At the horse rescue I volunteer at we have one of the hot air ones but I haven't touched it. So I flip the soldering iron style ones over and use the tip to push into the plastic, lifting and pushing, making it look like I'm running a bead with a welder. I'm getting penetration that way and getting both pieces to bond together completely. I'll follow up with melting some of the plastic over top of the repair and smoothing it out. The wire mesh I'll use for anything that will see abuse or that really needs the structural integrity. I melt it into the plastic though, whereas it seemed you melted it to the plastic. I will often follow up with reinforcing it by melting more of the plastic sticks over the repair. The staples I find come in handy when doing larger cracks or getting into corners as they come with different shapes. (Sorry this is getting long winded) I will still weld around the staples and melt more overtop of them as I don't have flush cutters and regular wire cutters leave a little metal exposed to snag your skin on. We've been repairing plastic feed buckets that the horses have split by walking on them or whatever happens. The repairs have been holding up great. I've even repaired a damaged 5 gallon fuel can. ATV fenders? Oh, soooo many. I've been at this for several years now and have fine tuned my craft. Even structural tabs that maybe a screw will go through or a clip have been repaired with zero failures. Just had to pull apart a Honda Foreman to adjust the valves. Months ago I had done plastic repairs to fastener tabs and clips. They're all still holding up and this ATV gets ridden multiple times per day. It gets used for morning and evening feedings as well as normal ranch use, even for moving cattle. I think if you refined your methods you'd see a lot different results, but regardless, you're able to repair damaged pieces, potentially saving hundreds of dollars with a very minimal investment on tools. Time however, it's a very time consuming process.
Good plastic welding is somewhat of an art form, and making sure you use the right weld method and rod for the kind of plastic is critical. It might be worthwhile getting an experienced plastic welder as a guest sometime and revisiting this one. I’ve seen good HDPE welds be stronger than the straight part and look beautiful, but that’s by an experienced plastic welder.
I experimented with a few of these last year and found the metal staples to be awesome for adding strength to the piece. For some repairs, they are enough to hold the piece together by themselves. For the strongest repair, I’ve used the staples, mesh, and plastic welded into the crack. If you hold the welder onto the mesh so it gets hot and actually melts down into the plastic, it’ll be a lot stronger. One thing I’ve learned is that there is quite a steep learning curve with this type of repair. I would LOVE to have that OIMERRY one. It looks like a do-it-all machine that will make professional-level repairs. Thank you for doing this video, this is something I wish existed in the past before I had to learn by trial and error what works best for plastic repairs.
I didn't even know these existed! I always used a flat iron tip piece on my soldering iron. I really like that jounjip one with the tip that allows you to feed the repair stick through it. Definitely getting one now before the price goes up!
After having just repaired a car bumper with a couple of cracks in it. I can say that the effectiveness' of the repair is really more about technique than the tools used to achieve it. I bought the Allturn gun with the staples and mesh kit, before this review. Melting the mesh into the base plastic rather than using the plastic sticks to bond it is far more effective. Cleaning and sanding the base plastic is really more for decontaminating it than for for providing a good bond. Melting the base plastic to itself rather than relying on the filler material for the initial bond is also the best. Try to use the filler material as filler, but to also melt the base material into it. The Allturn setup is a really good value at $35 and it works really well. That's the one I would recommend for the occasional plastics repair. It'll pay for itself the first time you use it and it comes with everything you need to tackle many repair jobs.
I do plastic welding very often to repair anything that breaks like plastic porch chairs and the grass exit Shute on my riding mower. It is always as strong or stronger than original. I do often use the staples to bond it and make it strong but the major key to plastic welding is to get the plastic melted very deep for maximum penetration. I try to get halfway through the thickness then again halfway through on the other side for complete penetration. even with the staples. and if you use wire mesh it should be melted deep into the plastic and not just stuck on the outside, the welding rods are really only to fill gaps in the plastic that the original plastic leaves as you weld it. Not to put a thin coat over the break as you did. I actually was surprised that it held as much in your tests as it did. But it was interesting to watch. I enjoy all the testing you do and often make my purchases of items based on how well they did in your tests!!
Wow. I always wondered how good plastic welding worked. I love all the comments and constructive feedback. What a great video idea! And what a great community. Definitely in my top ten UA-cam creators. Thank you!!!!
Awesome stuff. I have a plastic welder, I've used it to repair cracks and breaks in plastic bumper covers a few times. The staples are the way to go for strength for sure. You can make stuff look new again with enough time and other products! haha
I liked that you included jb weld. It wouldn't of occurred to me to out in a welder review, but it really increases the value of the results. This is why I've watched your videos before making major purchases (drill, generator, chainsaw)
There's one other method of welding plastic components together that I learned as an Airframe and Powerplant mechanic, following the Cessna 152/172 Series Service manuals: Chemical welding. In essence, take some plastic chips that match the plastic you are trying to fix (don't use Polyethylene on ABS, for instance), and dissolve them in hard solvent (MEK or full strength acetone), best done in a resealable mini can. Mix it up thoroughly, to get a smooth consistency of this now thermoplastic paste. makes sure the repair area is clean, then wipe the area with some of the solvent and let it sit for a minute or two. Then you fill the repair area with your thermoplastic paste like you would using JB weld and let dry. once the solvent evaporates completely, you should wind up with the plastic weld being completely indistinguishable from the base material, but I've never actually put that to the test. Since you put it into a resealable can, the paste you have made will stay ready to use almost indefinitely, and if it does dry out, just add more solvent. Thank you for listening to my idea. I did enjoy the video, Though as other people noted, using dissimilar materials when trying to weld some of the plastics did not do you too many favors. There was still really good information on the welders involved.
@@bostonmarketfeministbookclub Working at a flight school, I've done this kind of repair to a few aircraft, always on the non-structural fairings. The Maintenance manual definitely has dissolved thermoplastic bits as an acceptable repair under "Repair of Thermoplastics" in the Structural repair sections of Cessna 152 and Cessna 172 (Pre-R models) Series service manuals. In our flight school environment, this was almost entirely done for cosmetic reasons. Pilots squawked aircraft all the time because things didn't look right, even if it had zero impact on function or safety. But when pilots don't fly, school doesn't make money.
Some say with the staples, when you penetrate halfway into the material, you twist it slightly to gain more new material to anchor from...kind of like a twist-lock. I'm motivated to break something to test mine out that way 😁
I was really surprised at how well hot glue with wire mesh did. Seems to me like JB Weld is the most practical solution unless you regularly find yourself needing to weld plastic.
JB Weld is a chemical miracle. If it's mixed properly, and the surfaces are cleaned and roughened, and it's allowed to fully cure, it can do almost anything. I score surfaces with a knife blade or the edge of a tiny file, instead of using sandpaper. I feel it gives it a bigger tooth to grab onto, and it seems to work very well. SO glad I found JB Weld.
Just like traditional metal welding, polymer welding has one hell of a learning curve. Ive used hot air and iron style welding and prefer hot air because you have an indicator before everything gets messy.
Great vid. I can see that a decent soldering iron can cover the jobs of any of these, but the iron tip with a hole and triangular shoe looks worth buying / copying. One idea that came to me for testing was multiple buckets to repair so you could pressure test each repair. And with the butt weld test pieces, bevelling the join would really help as would much, much more heat and time before feeding in filler material. It looks like none of them melted into the parent material. The Beyondlife is beyond hopeless, however. It's not you it's him!
I use my soldering iron all the time to fix broken plastic. To make it look great you can file it smooth then hit it with a hot air gun. I use the hot air soldering station I have but any old heat gun would work. Just slightly melt the filed surface and it dries really smooth and does not look too bad. A temperature controlled soldering iron is better because you can dial in the temperature for the melting point of the plastic you are welded. Heating plastics too high will weaken them.
Part of the issue with bonding plastic is that the heat adds extra carbon, which makes the repair area more brittle on parts that have to flex (motorcycle fairings). You can use a soldering iron or wood burner. V notch you repair on both sides and gently heat the area with directed heat from a heat gun with a nozzle. Tack the parts together at several points. Get a wire screen patch cut, Fill the V notch with plastic, zip ties work well, and embed the mesh making sure to fill the v notch on both sides. Then use JB weld like Bondo to feather the repair on the presentation side. The other side can be left a bit rougher.
When I wad 18 I worked for an auto body shop..specifically I rebuilt plastic bumper covers. We had a few of those hot iron and rod type welders but they never got used. We used a plastic welder that used heated nitrogen to melt these gnarly 1/8” thick x 1” wide strips of some sort of plastic. The strips would go on the inside of the bumper cover and the outside would just get finished cosmetically. That stuff was invincible. You’d tear a new hole in the bumper cover before you pull the repair apart.
Very interesting. I have quite a bit of gear for plastic welding, but saw some new stuff in there to ramp up my gear lust! In my own experience, I've found that the first and most important thing is the type of plastic that you're working on. HDPE, ABS, and acrylic are all totally different. For most repairs, I like staples with steel mesh melted into the repair piece, and then additional material over top of that.
hey Todd !! i dont know about dedicated " welders " but I AM A HUUUGE JB FAN. i have done radiators, exhuast pipes and headers. also, intakes, blocks. and yes ALL KIDS of plastics from dashs to bumpers ..... misc household iems. it sands, fills, drills, tapabilitie, sand it, prime it n paint like bondo !!!! there r tricks n technigues to work the stuff. 1 is that like REAL welding FULL PENATRATION is paramount !!!!!!! another is learning 2 control how much hardner to use 4 the type of job ur doing..... more flex ..less flex etc !!!! it is a very versatile material !!!!!
Making battery packs using spot welders are hit and miss. A review of these would be fantastic. Great job with this one, Mr. Farm, always a nice Sunday with a tool review.
I'll second this! But there's lots of similar ones on AMZ and even the more expensive ones can have bad reviews either because of actual poor performance or bad technique. It's a tricky subject, perhaps just like the plastic welding test.
I use a simple soldering iron and mix the breaks together going back and forth lengthways completely mixing the two halfs together at the break. Works great for me. Seems like these methods just add stuff to the top and bottom and don't do anything where the two pieces touch.
I used a cheapo $20 kit a few years ago from Harbor Freight to weld the plastic gas tank on a Honda Element after my wife ran over a tire jack that fell off a truck on the highway. Not going to lie, even with the tank empty due to where the jack ripped into the tank, it was a scary process but it did work and it held for over a year while I had the vehicle before trading it in. I used wire mesh when I did the weld. Prior to having the Element towed 40 miles, I didn't even know plastic welders existed. This video definitely shows there are some much nicer options!
Something I've noticed is the method of sanding that you use is in only a single direction and that is hurting the overall strength of your repairs. When sanding you should always use a cross method. The idea is to provide the most surface area possible. You should be able to see little crosses in your sanding grooves. You will be surprised at the difference it will make. Also I noticed that you are a little impatient with your iron give yourself a little more time starting out to sink the tip into the parent material. Just like with normal welding you gotta get penetration. It's not like hot glue. You have to make both half's into a state of matter that is borderline molten in order to achieve fusion.
I bought 2 of them recently and used them right away to fix one of our large recycling bins. The Allturn is definitely one to go with. If you do it carefully and if conditions are just right, you may not even need to use the "sacrificial" plastic sticks to build up the plastic. You will want to use a Dremel sanding tool drop the height of the metal clip ends once they are embedded. Be careful about the temperature of the Allturn and how you handle it or where you put it to cool down because it is quite hot once used. I also bought the Harbor Freight one that looks like the Joonjip which seems fine for small areas but the Allturn was flexible with the items you can fix with it, it was fast, and seems effective.
Tip I picked up: You can chuck a short piece of 3d printer filament into a Dremel tool and use that as a stir welder. Works pretty well with some practice. Use the same type of plastic filament as the part you're repairing.
Didn’t Fran Blanche do a video showing some old plastic stir welding device that worked just like that? Either way, great tip about using 3D printer filament. I’ll have to try that sometime!
Not how you plastic weld, you use the tip to melt the plastic together then fill if needed with more material. Try and use the same material, however the fiberflex works really good.
@@ProjectFarm No problem, now I might have to do a how to video with my plastic welder...LOL You kept that tip off the base material, you need the base materiel to melt to bond The head with the feeder hole you put the head on the base material so that melts and you push in some new material through the hole. Maybe this is just an art and I have done it a LOT...best investment on the Polyvance I have ever made.
What i noticed was that on the polycarbonate you weren't using the appropriate weld stick. It needs to match the type of plastic you are working with. That's why they all separated on the polycarbonate.
Cheap plastic weld kits probably come with limited types of weld sticks. I feel that his tests are supposed to simulate the use of what comes in the kit, not specialized items you can buy. If some one wants to repair plastic they should do research to understand how to make proper repairs. Plastic is harder than stick welding. This channel is not to teach you to be a master stick/mig or Tig welder or to teach you how to repair plastic. Just to review products. He does a fine job on that.
Excellent tests! Out of necessity, I've repaired several plastic items, mainly with a 140v/100v weller soldering gun. As others have mentioned, I've had better luck heating the screen directly into the original piece & using minimal filler. Great content & thanks!
Loved this video!! A very common problem is cracked gas tanks. Perhaps you could use the plastic welding kits you already have and see which works best on cracked plastic gas tanks. If you do please be sure to use a new tank or one you have cleaned and are sure no gas fumes are present. Thank you
I worked at a plastic Fabricating company for many years. We built polypropylene water tanks for fire trucks. We used Laramy hand welders and Munsch extrusion welders
Can confirm. I have the Jounjip AND the Allturn for the staples. I've learned you need both, they complement one another. And you do indeed need a lot of practice. Last tip is to make sure you get the same weld rods as the plastic you're repairing.
I'm surprised you didn't try acetone - it's a great option for certain plastics when you can't use heat. Being practically as viscous as water, it penetrates deep.
I just purchased the Jounjip plastic welder (sight unseen) literally 60 seconds after viewing this video. I used one (with transformer in box) decades ago and the wire mesh held up fine. Too bad you couldn't torture a tool into extinction this time, but I still always enjoy your videos! I've made many purchases over the years based on your recommendations alone..
Could I request best electric pencil sharpener? Teachers are struggling with poorly made products. Compare them with cheap/expensive pencils and to the old crank sharpener in most classrooms still
Excellent tests. The staples are great for tensile strength and work better if you twist them once sunk into the plastic. I was really surprised the Ryobi glue gun did so well comparatively. Thanks for the video
@@ProjectFarm all glue fails on pe after some time, the only thing that works on pe is pe. Did plastic welding for some years, and the joke was always to invent a glue for pe and retire of the monney
Hot glue is fine at more or less room temperature but get it up to 95 or 100° or more and it will start to soften. A friend of mine hotglued new speakers into the dash of his Saab 900, onto the mounting plates that sit under the corners of the windshield, where the sun would beat down on the dash, and as soon as we had a hot day the speakers fell off the mounting plates.
Thanks for the testing. your tests more or less confirm my experiences repairing plastic which is that it is for the most part a waste of time in applications that require strength. Once those molecular bonds are broken not much short of sonic welding does much more than disappoints you when the part breaks again. Plastic has replaced a lot of items that used to be made of metal, it is not much fun to work with when it breaks, and regardless of the amount of plastic in the part is generally very expensive to replace something that if made out of most metals would have been easier to repair or wouldn't have broken in the first place. I just used JB weld original on a plastic housing that covered the intake end of a diesel air filter. There were 3 cutouts on the end that could flex a little to slide over the filter. All 3 places had cracked. I sanded and cleaned the areas then applied Original JB Weld along the crack opening the crack some so that some glue got into the crack then applied more glue all over the outside of the crack. upon installation one of the sites re cracked. It was on the intake side so that the air was still filtered so have not gone back to reseal it. The filter has to be loosened from underneath but the only way that it can come out is out the top of the engine after some of the inter-cooler piping and other things have been removed. Not fun and really not much of a problem. One product that I have had limited good luck is Seal-All. I have a 1984 Toyota Corolla that runs on diesel. It developed a very slight leak in the fuel tank. As a temporary repair I used Seal-All on the spot without draining the fuel. At the time it recommended that I use a single thickness of cardboard like a heavy end flap of a box lid or the cardboard backing of a note pad placed over the Seal-All and held in place for a short period of time. I did that temporary repair over 20 years ago and it hasn't leaked yet.
The Beyond Life one is a design used for heat welding vinyl and linoleum flooring. It requires a beveled grove, like welding steel. You use the hot air to heat both the parent and filler materials to just shy of liquid and press the rod in with the tip. There's definitely a learning curve and it's kind of becoming a lost art. Next time you're in a hospital, look at the vinyl floors, every 6ft you'll see the weld joint.
This was a fun video. I got the harbor freight plastic welder, and with a little practice and patience I’ve managed to make some fairly decent repairs. What I found worked the best was using the triangle tip to gouge out a channel into the crack or split, and then using filler material to join the two pieces. I let one side cool and then repeat the process in the other side, if I can get to it. then build it back up over the surface so I can buff it back down with a scotch wheel.
I was committed to buying a new headlight bucket for my 240 Volvo, but I figured since I had it out anyway, why not try to fix it (I hadn't found one yet). I used fresh super glue (cheap), and finished it off with baking soda. I was pleasantly surprised to see the shattered plastic (three pieces) all went together and held up under light flexing (stress they shouldn't be exposed to in real life). I did fill some of the cavities in the reverse side with epoxy, since I had it on hand. Has held up so well, that when I finally did find the correct part, I passed it up. In other applications, I've dusted one side of the break with baking soda, and applied CA glue to the other part. Instant, strong bond.
The weekly content never ceases to amaze me-week in/week out everything applies to our day-to-day needs on a genuine/useful level. Thanks Todd. God bless. Btw, I love hearing you say: *"Made In The USA."* It's good to know we're cranking out more than potato chips, SNL skits, and corrupt politicians. 😳
I’m at the point that I will pretty much pay double for some thing if it’s made in the US knowing that I’m providing work locally, have a good customer service, and the product people will stand behind. I needed a screw for a Leatherman tread that I couldn’t find anywhere and simply called the company that’s local in the San Francisco Bay area. I was shocked when someone who spoke English answered their phone and sent me the screw in the mail No charge. Would be a great video of you highlighting companies that do this(even if some of them do have components built in other countries)
I got my first plastic welder 2 weeks ago, the "Sonnler" SN-B150, it looks exactly like the Altern , but speced at 150 watts power, the staples will get Red Hot in seconds, I've been repairing broken Motorcycle body parts , battery tray, rear fender, side panels etc. The squilly shaped staples give more support than the straight ones, i find it important to let the staple and plastic cool , before removing the welder from the item being repaired, to prevent pulling the hot staple out of the repair , also on your bucket, i would have used the squilly Staples , and put them length wise on the cut, using two or more not just one straight one across the cut, your cuts simulated a stress break, and should be supported across the complete break, you are always very thorough in your testing, but i don't think the breaking test reflected real world experience, as most plastic is either broken by impact, or by repeated stress such as vibration or repeated flexing, i don't expecting my plastic weld repair to be as strong as the original factory new, i just want it to hold together and extend the life of my motorcycle or generator or patio chair etc, seal my bucket until i buy a new one, repair a cordless tool storage box etc..
The reason you had problems using the hot air welder is you set the temperature way too high. You need to set it high enough to melt the substrate and rod but not melt either one to liquid form. For HDPE I would probably set it to 325 to 375 F. For thicker materials you can got higher. If used properly, the gun will melt the contact area of substrate and rod, creating the weld bond. I’ve used this type of gun for a lot of welding HDPE, PVC, ABS, PP with great results both for physical strength and water tight containers. It does require more skill and practice than the hot iron methods but the results are much cleaner. Not what you experienced.
FYI I use hot air guns and hot glue guns for a living, the Beyondlife type hot air gun is not for glue sticks, they are specific for poly ethylene or similar welding rods and they work great for building and repairs of rotomolded pieces. Not for plastic buckets . also when welding the two HDPE square rods together ya really botched that up. the objective is to melt both ends then force them together, wait till it cools off about a minute, release pressure, then wait for complete cooling... now you essentially have one rod. it would have been the strongest test result.
Got one for you, buddy! Soil testers - there's a huge amount of these sold on amazon and elsewhere but nearly NOTHING online about the quality, accuracy, or longterm reliability of these. I notice in some reviews that you just abrasively clean the contacts/sensors frequently, some mention how deep it needs to go to get a good reading, others mention how much prep into the soil is needed to get a good reading (watering, tilling, etc). Plus I'd really like to see how accurate they are compared to a lab test. Since you're a farmer I bet you've got great thoughts on this too. Hope to see this one soon!
Here’s the list of products reviewed. More details in the video description. Thank you!
Beyondlife: amzn.to/440PxbG
RXXXWELD: amzn.to/3DQy5ft
OIMERRY: amzn.to/3qkKdCh
JOUNJIP: amzn.to/445DE43
Allturn: amzn.to/44eeIYw
Ryobi Hot Glue Gun: amzn.to/3YyYXtC
J-B Weld Plastic Bonder: amzn.to/3s6s77B
J-B Weld Original: amzn.to/3KAp3qo
I'm sure you knew this, but, the ideal repair method for those comparison slices you made would be to slice a pair of ~45° cuts that intersect the slice at the back so that the plastic, so that the hot plastic 'stitches' the slice shut. After which, you sand it to make it look good. That is under the presumed objective that this not only to seal it, but to make it look undamaged.
I have broken polyester back of office chair. Which one would you recommend?
As an automotive technician I use the jounjip kit and found that for best results melt the wire mesh into the plastic before using the filler. Often times it’s stronger than the original piece and has saved my butt countless times. There is a learning curve and results become stronger and look better with practice.
That's a great tip! I should have done that! Thank you
Yeah you need to get in there melt the damage so it can fuze together.
I like this....well stated.
You beat me to it. I said the same thing in my comment. It's a bit of a learning curve, but once you get it right, the repair is often stronger than the original piece. It's best to heat the mesh directly to melt into the original plastic then use the filler.
I was thinking the mesh should definitely be in place before inserting the staples on the products that use them.
As someone who suffers from Analysis Paralysis on anything I purchase I'm truly thankful for the time and energy you put into each comparison
Thanks so much!
Is that what it's called? I guess I have a name for it now at least.
@@Bigdude0444 it's a widely used term in board games too.
What you said!
@@Bigdude0444 Yep. Common affliction for those of us with analytical minds, a touch of ADD and a skosch of perfectionism.
I really appreciate you deciding to do a video on plastic welders and hot staplers as I've used both for several years, and was excited to see this one come out. Unfortunately, the processes used in the video were all wrong and completely invalidated the tests. Most of the principles used in metal welding apply here too.
1. You should make a small bevel at the junction of the 2 pieces, on all sides to be welded.
2. The plastic representing the base and the plastic representing the filler should both be melted and mixed together.
3. You can buy different types of filler rods online. The plastic used as filler needs to be the same as the base plastic.
4. The wire screen is supposed to be completely embedded into the base plastic. Not just "glued" on top using filler.
5. When inserting the staples into the base plastic, you should end with a slight twist to completely embed the staple and cover the entrance grooves.
Would love to see a redo of this video if you decide it's appropriate.
Thank you.
His video pretty much showed how most uniformed DIY guys would proceed. Can you recommend a video or source that goes in to detail for maximum efficiency? Thanks.
I hope he revisits. There’s always great comments on PF’s videos but this one has some top notch ones. I really wish I had the time to sit here and read them all!
Thanks for being the most thorough and honest reviewer out there. Your lack of taking sponsors helps you stay unbiased. Thats why we all love your content. Keep it up!
For those who don't know what HDPE means, it means high density poly-ethylene, and is manufactured differently than is Poly-ethylene.
HDPE is typically used for fuel tanks, and fuel and oil containers in consumer goods.
For one that is desperate to fix a plastic gas tank, cutting an oil container into strips the color of the tank, as this is the same plastic in both. I repaired a generator gas tank this way, and used a 100w soldering gun. It was leak proof, and was tested by two different mechanics, and they both approved.
For white plastic repairs, isopropyl alcohol bottles are HDPE, and work just as well.
Great tips! Thank you
I hadn't thought of using plastic bottles, thanks.
Milk jugs are also HDPE. Look for the triangle with a 4 in the middle.
There are many videos of making really cool things via melting milk jugs in the oven and using the block of plastic.
It's a very interesting rabbit hole to go down.
@@TheSshadow7 I've got a 30 year old scar on my hand from burning a milk jug as a kid, got a good drop of molten plastic on my hand 😂
HDPE is extensively used for water piping and underground dedicated fire fighting piping (usually for industrial applications).
I've done quiet a bit of plastic welding at a previous job and one flaw in this test I noticed is you're using dissimilar materials. For instance, if you're work piece is polyethylene you need to use a a PE filler rod and if it's polypropylene you need to use a PP filter rod. Using PE filler rod on abs you will never get it to bond and make a strong weld. Just a bit of advice if you ever do another plastic welding video, make sure to get filter rods of the same family as the work pieces to get professional results. I do like how you compared hot glue and JB welds.
Acrylic, Polycarbonate and ABS are compatible. It's messy when done with low DIY level tools.
Does plastic had to have concave like metal welding prep?
@@rc-t3k if I'm understanding your question correctly it doesn't matter as long as you can melt the material and filler rod slightly to get everything to bound together.
Yeah I use the beyond life style plastic welder to make polypropylene tanks and the high heat is required. That bucket never stood a chance
mixing with different plastic is not good at all will yield random strength (bonding) results as seen
I work in the plastic dam lining industry. Plastic (particularly HDPE) oxidises quite rapidly, we what we do is use an angle grinder with a flap disk to scuff away that layer before doing any extrusion welding as it makes the bond much stronger. Also, for butt joins you need to fillet/v-groove the edges to increase the surface area, and also ensure all contact points are at melting temp so the new material can become part of the old. P.S. If your hot air gun is melting holes in stuff, turn it down - It's too hot! Just like MIG.
Thanks for sharing.
Absolutely right about the need for fillet in butt welds. 45 years ago we used hot air guns on PVC sheet that had a feed hole for PVC filler rod. We used a hand held "Scarcen Scraper" to cut the v shaped grooves immediately prior to welding, and isopropyl alcohol to clean the sheets. Probably not a good thing to breathe up, nor were the shredded fibreglass particles we breathed up from the adjacent workshop.
Thats a standard in all welding i guess
I have some cracks in HDPE totes (Rubbermaid Roughneck). I had a hard time trying to get undamaged totes in the 50 gal so I decided to try plastic welding instead of play the return game (in hindsight I should have just ordered 3-4 and play mix and match since their shipping packaging is terrible).
If I want to attempt a HDPE weld of some hairline cracks, what's the best method to try to weld these? I don't want to fill totes with weight and then cause more cracking.
I plan to practice on milk jugs to see if I can get a method to work, but any hints would be nice. Can I tape a non-stick material like teflon and then use a heat gun and apply pressure to the area, then let it cool and peel the teflon off? I also have the Jounjip and could try to weld plastic from milk jugs since they seems to both be HDPE.
I've done a lot of plastic welding on airline luggage pods. The welder I used is similar to the Beyond Life type which has a preheating air jet. They work extremely well. The trick is to let the hot air do the work, and then force the rod into the molten plastic. It's about technique. For something as thick as your test pieces, you need to make V-cuts into the ends and then weld both sides. It would be very strong if done that way.
Thanks for the constructive feedback.
Having worked at two machine shops that employed in-house plastic welders, I concur withe the use of the Beyond Life type welder. There were two types of tips I saw frequently used, one was like a 1" hot knife that they would run along the bottom of the chamfers to tack the parts together. The second tip was like the one shown where the filler rod was fed through the tip to preheat the rod and the path the rod was going to be laid in. The trick is to only heat the air/tip enough to barely melt the plastic. You want both the part and the filler rod just soft enough to use the tip to force the rod into the groove made by the mating chamfers. The finished bead should be proud of the surface.
100% definitely want to bond into the base plastics an the bevel will get a good through an through bond. What was done here was a patch/makeup job
Using a hot air jet is a fairly old method. I learned it 20+ years ago and it wasn’t new then either. Trick is to treat it more like a tig process. You are melting the substrate with the air jet then adding the rod. Keep the air jet pointed at the point where all 3 meet and slowly move across your joint. Definitely takes practice to get the speed and heat right.
I came here to say that. I used to work at a company that made plastic enclosures and we used similar style welders. There’s a learning curve that I never climbed, but with practice the bonds can be ridiculously strong.
PF added the weld before the mesh then additional weld on top. When it comes to plastic welding, I usually heat the mesh directly to melt into the original plastic before adding weld with the sticks. I've found this to be a better way of reinforcing the structural integrity.
Yes. This method in my opinion makes it almost stronger than original.
@@NoughtSure It truly depends on the thickness of the plastic combined with the expected forces applied during active use. I'm sure something as thick as a kayak would do slightly better with the staples by themselves than it would with the mesh. This is due with the forces coming from the top down rather than lateral force. With that being said, for a kayak, I would probably do both staples and mesh due to the fact that the mesh has a wider surface area to hold against any lateral force.
One of the biggest flaws, if you ever want to revisit this, is that the plastics need to be flame/plasma treated if you’re using epoxy (JB Weld) or other adhesives on them. We use epoxy all of the time to bond to plastic parts, the ONLY way they stick is if you flame treat or plasma arc the surfaces. Sheet molders/casters may also use mold releases and those have to be completely removed/burned off for the adhesives to work. Easiest way is to just use a blow torch and barely melt the surface, it’s essential to get the epoxy to bond. We’ve had employees forgot to flame treat plastic parts before potting and the epoxy pops out like a cake in a well greased pan.
Few people know about flame treatment before adhesive bonding and its the easiest thing to do. A butane gas torch with a clear/blue flame will work. You can test the surface energy using dyne pens (>38dyne-cm should be good) or even a distilled water fog spray to see if it wets out on the surface. If you want it more fool prof you can also buy handheld corona or plasma treaters that will do the same thing, but with less risk of burning/melting. However, they are $$$!
I wish I knew that before I tried to stick together some broken nylon parts with epoxy. Popped right of, faster then it took epoxy to cure :/
I sorta discovered this on my own when gluing fittings into polycarbonate tubes. On some, I flame polished the machine marks from where I cut them, on others, I just sanded and cleaned with isopropyl. The ones I flame polished have such and incredible bond that I'm pretty sure it's stronger than the original material! The other ones just kind of cracked and felt like the glue never cured.
I was thinking it might have had something to do with tempering some internal stresses within the polycarbonate that locked in during manufacturing, but after reading your comment, it makes so much more sense!
The thing about this video is you may not have seen that he is not using molded parts and he sanded it down before gluing so reconsider that he might be using it properly for epoxy but other parts he should have melted mesh into plastic to get best results
I tried spin welding polypropylene and the fittings kept popping off with little effort. The interface between the parts always seemed waxy. She's flame treating sound like something that could help with that defect?
Technically speaking, I am a professional plastic welder.
Some tips.
Hot air welders are the best, they just take a little practice. The key is looking up the proper welding temperature, for HDPE it is 560-570 F. If you are too hot it will ruin the integrity of the plastic.
Use the same filler material as the base material! Different plastics do not stick to each other.
The base material and the filler material should be heated/melted the same amount and allowed to cool before you move anything. You are welding, not gluing despite how it may seem.
Lastly, cleanliness is very important. Instead of sanding, I suggest scraping. You need to remove the oxidized layer of plastic on top because that cannot be welded properly. Cleaning with alcohol is important too.
Look up videos on proper hot air plastic welding for more info. I think Leister has helpful content available.
I have an SMD hot air tool which is handy with its pinpoint nozzle and fine temperature control.
get the extruder gun, think liester makes the smaller ones, i've only used the bigger ones, worked on Geomembrane 40mil to 80mil HDPE and LLDPE
@@dubmob151 I was wondering the same - whether my hot-air rework station could be used as a hot-air plastic welder. My station supports temperatures between 100 to 500 celsius (212 to 932 fahrenheit) along with adjustable air flow and different size nozzles, so maybe, but I'm sure technique will make a big difference between messy failure and success.
@@brettski74 it should be ideal because you can dial in the temperature exactly as needed to melt without burning-
The wire mesh should be thru-melted into the base piece being repaired and THEN have filler added to smooth. This can ONLY be done with the higher heat tools....also, when you retest using this method you should also add steel wool as this has been common for years and in pieces that really NEED to remain flexible without breaking the individual strands of steel wool seem to add a lot of flexibility without sacrificing breaking strength.....but as always GREAT FREAKING JOB!!!! One of my top 5 creators on UA-cam no doubt
I was going to suggest melting the screen in as well. It worked well while repairing a plastic ATV skid plate and I used the side edge of a box wrench to further push in the screen. The wrench cools the spot to secure it as you work the screen in.
I have been plastic welding as part of my job for 35 years and steel wool is a poor choice since it is covered with oil and would quickly rust once the oil coating is cleaned off. Stainless steel screen is all you need but if you want something like steel wool, get some s.s. shavings from a machine shop.
Project Farm content is always “VERY IMPRESSIVE!”
Thank you very much!
Another VERY IMPRESSIVE! Set of tests.
@@ProjectFarm
please do sds hammerdrills, diamond blade for grinders,
jackhammers if possible
@@volvo09 I love the way he says "Very Impressive!" and "We're gonna test that!"
We're gonna test that!
FYI: Not only showing us what are the best products but helps most of us who have never tried any form of the tools you show....a big THANK YOU from all of us.
Thanks so much!
In this particular instance, the "best product" can very much be situational and technique makes a big difference. When plastic welding with HDPE, PE and PP plastics ideally, you want to melt the original material back together before adding new material. If you're using staples or wire mesh, melt it into the plastic before adding new material. The new material should fill in the void left from melting the original plastic back together. This will give the best result and in most cases you have to add very little new material. If done properly, the repaired area will be as strong or stronger than it originally was.
I've been welding plastics for 10+ years now after an autobody guy showed me his methods. I've adapted it over time and have had great success with aluminum window screen mesh, 2 part epoxies, and a $20 Weller soldering iron I purchased from Home Depot 10 years ago. I've fixed several different types of equipment and haven't had any failures that weren't from user error after the repair. Never had luck with a hot glue gun when I attempted it. Great video! I always check your channel before making purchases on tools lol. Keep up the great content.
Thank you!
🤩 I used a JB Weld product and plastic strips from an electrical box to fix our old pool cleaner head: worked fine for two more years! Plastic welding is something I should learn, however! Thank you Todd! 😎✌️
Glad the repair worked! Thank you
The problem with plastic welding is knowing the exact plastic and if it's got any additives.
I worked in a plant making dielectric insulators to nylon (nylatrol and other nylons) for chemical rated bushings.
Some of that stuff was almost like oil-impregnated bronze but without being labeled as such. Imagine trying to weld oil impregnated bronze 😂
Awesome! I have a kayak hanging in the garage that has a crack from an encounter with a pointy rock. I have debated the JB weld vs a welder. Many years ago my father would repair his green Colman canoe with quakerstate oil bottles... used some hot melt glue and a propane torch. The smell flooded back to me as I typed.
Keep up the great work. Cheers from Wisconsin!!
Thanks, will do!
I have zero experience with these gadgets but we routinely repair abs plastic tabs that are broken by knucklehead mechanics using impact tools on semi truck dash parts. We use a combination of wire mesh and fiberglass mat/resin to build new tabs. These trucks see 150k miles a year of pounding on the interstate and we have never had a failure. We have found that the few times that guys have come in with DIY plastic welded repairs, the plastic around the repair is brittle from the heat of the repair tool and is the point of breakage. Great vid Todd.
I briefly worked for a company where we welded together huge research fish tanks with a plastic welder like the Beyond Life style you have here. The technique is very similar to arc welding and takes a lot of time to learn how to use well, but it did a great job of welding plastic parts together. We didn't use any metal reinforcement on our plastic tanks and they held up just fine with hundreds of gallons in them. The trick is to get the heat setting correct first and foremost, and then you have to move fairly quickly to avoid burning through. Like I said, it's just like arc welding, so you have to put some hours in to get it right.
Harbor Freight sold a tool similar to this years ago. I got one, but I haven't used it as I have nothing to test on...I knew I needed to develop technique first before using. All the stuff I have (classic motorbike plastics) is a one-shot deal...either I get it perfect on the first try or it's ruined. Sounds like I might have to take it to a professional!
@@anonymousplanetfambly4598 Same story, got the HF plastic welder but have never used it because I cannot find a scenario.
For ABS, acetone welding and ABS/acetone slurry have never let me down. Sometimes it takes a very long time for the acetone to evaporate out if the slurry is put on very thick.
When doing plastic repairs in the past I have used a soldering iron, I find that works well enough for me considering its very rare that I repair plastic.
Thanks for another great video as always :D
Agreed! Tried the "plastic welders" and could never control heat or finish. A sharp bladed soldering iron cuts a groove that the plastic rod fills.
Plastic welders are cool, but I'd really love to see you test budget multimeters. You can probably use a fluke as a control to compare the budget multimeters one feature at a time, ohm's, volts, amps etc.
Great suggestion! Thank you!
Yes! I second this suggestion!!
Having used countless multimeters over the decades, I've found even the cheapest have reasonable tolerances and provide good results.What they don't have (and which would be difficult to test), is the ability to withstand the test of time. My Fluke is ancient and could use a fresh set of sockets. All the cheap stuff was binned years ago.
yes! I just bought a Snap-on basic MM, one with the big display. I love it! Still though, it wasnt cheap. How accurate is it?????
I have tried several small multimeters looking for one that would take up less space than. a Fluke 179. The most frequently evident shortcoming of the less expensive meters is how long they make you wait before they settle in on a reading. The two I ended up carrying are the tiny Fluke 107 and the Hioki pen meter. Other than its larger size, the annoying thing about the tiny Fluke is the lack of probe clips on the case. Of course, the safety category should be the highest priority consideration, but it's hard to want to test whether they're lying on that score.
I think you need to revisit this one ASAP. I thought that the Polyvance plastic welder was the model that most people that were serious about plastic repair bought. I’m disappointed that this wasn’t added to the line for testing. Another point I’d like to add is that (Like with most things) technic is key and was lacking a little bit. I just want to see a fair shakedown. As always, Thank you for your Time and Dedication to making these unbiased videos! It’s greatly appreciated.
Thanks and you are welcome! Thanks for the constructive feedback.
I think most people are going to do this type of repair one or twice in their lifetime. So doing these tests without having any experience or practiced skill with each system is a real world example to base your choice on.
@@troyreed7942 Exactly. People aren't going to become expert welders before they do something like this, not at this point in time anyway. I found this very real world and great for the average DIYer.
@@troyreed7942while what you say is true, the title of the video is "best blastic welder" not "easiest plastic welder for beginners" As is typical with this channel, a lot of care is out into the testing process, and unfortunately this product requires a lot of technique to get proper results. Either the title of the video should change, or it should be revisited and updated!
I’d be interested in seeing the PolyVance tested as well.
You do a great job testing, but with almost 3M subs, it isn’t surprising a few people have something to add.
I always appreciate your video's! I do have to say that there seem to be some glaring problems with this test and I'd suggest if you do it again you try some of the following.
1: Use a soldering iron with a fairly small tip, maybe between 1/16" - 1/8" and press it down through the plastic between the crack/break. Then either do a stir weld technique (spinning the iron or piece) or make small circles and move along the crack as it melts. I usually melt about 2x the width of the soldering tip. I've even used the tip of a hot glue gun if it gets hot enough
2: you need complete penetration of the heat on both sides of the plastic. If it is thick plastic I suggest warming the area (about 1-2" on either side of the crack/break) some how. A heat gun, hair dryer, hair straightener (ironer/flattener), toaster, toaster oven, torch (be careful & don't get too close). The warmed plastic melts much easier & kind of tempers the weld line and it seems to be less brittle
3: Use filler plastic of the same type. Identify the plastic by the recycle number (1-7 I think). Most 5gal buckets are HDPE and I use one of these for filler/patch material. Just cut strips to different widths. It's really nice to have some very thin ones to be able to feed it into tight areas.
4: Apply the staples after making the weld described above. Apply a top layer of plastic if desired. I'm sure you can make staples from any metal, even normal wood or cardboard staples (heavy duty shipping staples that so love to slice people open). Just bend to shape & heat with a torch.
You can bond 2 layers/sheets of plastic together (on top of each other) at the edges by using a thin soldering iron tip about the same diameter as a single layer of plastic is thick. Do the spin weld or small circles with the tip inserted as far as possible along the edge.
Been doing steps 1 and 3 with a cheap, chisel-tip soldering iron for a year and it works great, especially on cracks. And is neater than most of the demonstrated techniques.
This is great stuff. I have fiddled with plastic welding just enough to know its insanely complicated. Much like metal welding, you need the appropriate filler rod. Can't use ABS rods on PC base material or such. Prep is key too, I repaired a HDPE tank for a boat lift, and I had to carve out the crack to get some good penetration and actually stick the new filler plastic to the old plastic. Ended up holding up great for a long time, but the learning curve was a challenge. Thanks so much for making a great video!
All great points! Thank you!!
The beyond life welder requires a lot of practice and technique to use right but way more versatile. We use that style of welder for vinyl floor welding in hospitals in surgical rooms. You can't use any of the other style welder in situations like that
Id recommend looking up vinyl floor heat welding. It should give you a good idea for how to make a good hot air weld.
Nowadays even if I do not have a hot air gun, If I need to weld plastics I will melt both the base material and the filler rod right at the Joint area to get a very good repair. Similar to tig welding
Great feedback on the beyond life welder! I really struggled with it! Great tip on making a strong weld too!
@@kittytrailI install welded vinyl flooring and I like Steinel heat guns. They're a lower price than the Leister guns but seem to be of similar quality. I think the Steinel guns are made more for flooring so they don't have to be as powerful as the Leisters that are more designed for roofing. I know on my Steinel I can weld floors with the heat and fan all the way up but if I try that with a Leister I'm scorching the vinyl unless I'm moving fast and perfectly smooth. And that's with a good Turbo brand speed welding nozzle on both guns.
@@ProjectFarmBetter quality versions of that tool have independently adjustable controls for heat and fan speed. I also believe the Chinese knock off versions use weaker heating elements with a duty cycle that causes fluctuations in air temperature. It's the kind of thing where the quality of the tool makes as much difference as the skill of the operator. Don't beat yourself up, there's a steep learning curve and using cheap tools is a handicap by itself.
@@simpsonryan32I have two types of Steinel heat guns, the traditional gun shaped, and the inline style I bought specifically for plastic welding. Where can I buy one of those Turbo tips you spoke of? I only have narrow, wide, and heat shrink nozzles.
@@simpsonryan32 yep, the Steinel ones are fine too and they also make quality heat guns for lots of other brands too. 😉👌
still preferring, for my work, them Leisters as they can run for hours without much temp variations in the output. 😽
I appreciate the video. I was planning on ordering one of the Allturns for installing the staples to help strengthen the welds that I occasionally need to do and this seems to confirm that it will help. I have just been getting by with a soldering iron while doing these repairs. When I do a repair, I first clean the plastic with soap and water and then rub it down with rubbing alcohol. I then stitch the existing plastic together with the tip of the soldering iron going perpendicular to the crack. This holds the pieces together while I'm working on it. I then go back over it with the tip angled down at a 45 degree angle to create a V pocket into the crack. This gives me a pretty good weld with the existing plastics. I then melt additional plastic to the V pocket and work the new plastic into the old. I'm sure I could make stronger welds if I knew how to identify what plastic I was working with and obtained the correct filler plastic but since I don't know this I just do my best. So far I haven't had a repair fail and the plastic that I typically use as a filler is the black automotive plastic that I find that at almost any intersection from traffic accidents. Most of my repairs are on plastic parts on mowers and other lawn care equipment. I only end up plastic welding once or twice a year.
Thanks! Thanks for sharing.
This guy never fails to provide us with amazing comparison content
Thank you very much!
Very compassionate.
Yes but he should've infuse the steel mesh into original parts not on added plastic becouse then it gives the strength to plastic
@@odoroussmegma2191 lol
@@ProjectFarm your welcome
i love your show to see new and cool tools. came for the tools, stayed for the comparisons.
Awesome, thank you!
Good video, I've been using a soldering gun to repair plastic for years now.
Word of advice, place/clamp the wire mesh on the plastic then use the welder/iron to heat the mesh till you can press it into the plastic. Then use the plastic rods to cover the mesh so it can be sanded smooth.
Another great video!
I used black zip-ties, a big flathead screwdriver, and a propane torch to fix the plastic tank on my radiator. Worked great for over a year. I would rather have had a hot iron like these, but when you have to get to work. You use what you've got.
Thanks! Thanks for sharing.
If it worked only for a year it didn't work great it was a patch
Cheap zip ties are made from plastics with low melting points and as such are not a great choice for repairing radiators. Might be why your repair did not last forever.
Radiators I think are usually made from glass reinforced high temp nylon, repairing them with the same material would give the best result.
@infernaldaedra an emergency repair .eant to get you to work that day, that last over a year is a win. Any plastic weld job on a radiator tank is likely to be temporary, it dirty hot and under pressure.. all repairs are short term patches in that setting..
The big surprise for me was the hot glue. I NEVER would have thought it could hold up as well as it did. Great video, Todd!
Thanks! Thanks for the feedback.
I use hot glue for everything, even to this day years and years later some of my pieces I weatherproofed are holding up and keeping water out.
@@elitescouter I remember a "weatherproofing" stick made for hot glue guns. Easy to apply and remove.
I noticed the plastic glue sticks are much better than years ago. I had some glue from 15 years ago that is brittle and doesn't bond well, and I recently bought some sticks and they hold and glue great, much stronger and flexible.
@@elitescouter To be fair, that's also basically how Apple weatherproofed the new Airpods Pro 2, just filled the interior seams with globs of hot glue.
You do such a great job with your reviews. For plastic repair as many others have noted, there is a lot more to know to make successful and durable repairs. The first thing to know is when to give up and replace the piece rather than attempting a repair. For many plastics in commercial use, a repair will never truly be successful.
The key ideas to know are these: first - know which plastics are which, and what repair techniques can and do work. For many thermoplastics that means knowing what temperature to use, what pressure, surface removal, and technique. For some, heat is not the answer, and some glues may be effective, at least temporarily.
For some plastics (fluoridated polymers like Teflons) high temperatures are a no-no, and exceptionally good ventilation is required. Best is to not attempt to repair those if you do not know. At high temperatures these plastics give off highly toxic fluoridated organic compounds. These can be fatal. For beer drinkers, attempting to repair these with poor ventilation can rapidly lead to nausea, giant purple splotches, flu like symptoms and a trip to the emergency room where the doctors will be baffled.
For common plastics like the olefins (polyethylene, polypropylene and copolymers of these), repair is easy. First drill a small hole right at the ends of the fracture. This terminates the break so that it doesn’t continue. Next, champfer the split so that the full thickness is exposed and oxidized polymer is removed. Next, use a rod of the same material and a heat gun to gently raise the local area to the “glass transition temperature”. This is just shy of melting. The visible properties will change slightly. It will turn “glassy”. Now gently insert the rod into the fracture and melt it along with the base material.
This is similar to metal welding, but you don’t make a “puddle” or use circular motions. Gentle straight motions are fine. Just as with metals, thick cross sections may require two or more passes to fill the fracture and melt the entire surface together. The end result will be a smooth surface. It will be quite noticeable unless you have exceptional technique. Sanding and then surface flowing with mild heating can create a very nice joint.
Some plastics, such as highly cross linked polyethylene or polybutylene may not successfully be repaired in this way. Others like ultra high density polyethylene may appear to be repaired, but will fail later. What happens here is that the polymers don’t truly interpenetrate. Instead the surfaces weakly join, and a fracture will reopen later as the join line splits.
High density polyethylene can be successfully butt fused or be welded. But careful control of temperature and pressure is required, and a good eye is essential. If the join has a right angle or worse, it will fracture. The transition must be smooth with no distinct corners.
Other plastics work similarly. Which can be successfully joined or repaired depends on a lot of factors. Knowing what plastic you are dealing with is key.
And just as with metals, it is possible in some cases to seemingly join dissimilar materials, only to have them fail later. Just as you can weld monel to stainless steel in a seemingly perfect join, only to be able to shatter the weld by rapping it an hour later with a hammer.
Some plastics, like PVC can be easily repaired using solvent based glues. However, it is vital to know why the plastic failed. PVC fails easily under UV exposure. It is also a “garbage” plastic with dozens to hundreds of chemical additives. Most common are phthalates. These leach out with warm caustic solutions that can redeposit into the plastic in another place. As a result, one section of pipe for example can become extremely brittle, with another section turned into something akin to rubber. Phthalates are toxic. PVC should NEVER be used in drinking water systems - despite that being allowed in many jurisdictions.
Etc…
Thanks! Thanks for sharing.
Wow! This is a really good idea for a review. I have looked into solutions for cracked parts on my dash and stumbled across these kits a few times. Much appreciated. 👍
Thank you very much!
I think you should re-do this one and give it fillets or somehow else melt the joint. From what I've done and seen others do, it helps to (if possible) get the break melted. Otherwise the only strength comes from the thin layer you applied after the damage. Since it's plastic, it's possible to melt it back to almost original.
Thank you for sharing!
Thanks for also providing a forum for folks with experience to give tips in the comments! I learn a lot from these videos but also from reading what everyone says after
You are welcome!
I have the Harbor Freight model, similar to the RX Weld, but same colors as the Jounjip. The Jounjip tips will fit as replacements but you need to rethread them as they are a bit larger (and more durable). I also have the hot staple gun, just one of the $25 ones from Amazon, they're all the same. Staples are universally sized. At the horse rescue I volunteer at we have one of the hot air ones but I haven't touched it. So I flip the soldering iron style ones over and use the tip to push into the plastic, lifting and pushing, making it look like I'm running a bead with a welder. I'm getting penetration that way and getting both pieces to bond together completely. I'll follow up with melting some of the plastic over top of the repair and smoothing it out. The wire mesh I'll use for anything that will see abuse or that really needs the structural integrity. I melt it into the plastic though, whereas it seemed you melted it to the plastic. I will often follow up with reinforcing it by melting more of the plastic sticks over the repair. The staples I find come in handy when doing larger cracks or getting into corners as they come with different shapes. (Sorry this is getting long winded) I will still weld around the staples and melt more overtop of them as I don't have flush cutters and regular wire cutters leave a little metal exposed to snag your skin on. We've been repairing plastic feed buckets that the horses have split by walking on them or whatever happens. The repairs have been holding up great. I've even repaired a damaged 5 gallon fuel can. ATV fenders? Oh, soooo many. I've been at this for several years now and have fine tuned my craft. Even structural tabs that maybe a screw will go through or a clip have been repaired with zero failures. Just had to pull apart a Honda Foreman to adjust the valves. Months ago I had done plastic repairs to fastener tabs and clips. They're all still holding up and this ATV gets ridden multiple times per day. It gets used for morning and evening feedings as well as normal ranch use, even for moving cattle. I think if you refined your methods you'd see a lot different results, but regardless, you're able to repair damaged pieces, potentially saving hundreds of dollars with a very minimal investment on tools. Time however, it's a very time consuming process.
Thanks for sharing.
Underrated comment. Also, goes to show how much practice, technique, and experience 'factor into' a good plastic weld.
Good plastic welding is somewhat of an art form, and making sure you use the right weld method and rod for the kind of plastic is critical. It might be worthwhile getting an experienced plastic welder as a guest sometime and revisiting this one.
I’ve seen good HDPE welds be stronger than the straight part and look beautiful, but that’s by an experienced plastic welder.
I experimented with a few of these last year and found the metal staples to be awesome for adding strength to the piece. For some repairs, they are enough to hold the piece together by themselves. For the strongest repair, I’ve used the staples, mesh, and plastic welded into the crack. If you hold the welder onto the mesh so it gets hot and actually melts down into the plastic, it’ll be a lot stronger. One thing I’ve learned is that there is quite a steep learning curve with this type of repair. I would LOVE to have that OIMERRY one. It looks like a do-it-all machine that will make professional-level repairs. Thank you for doing this video, this is something I wish existed in the past before I had to learn by trial and error what works best for plastic repairs.
I didn't even know these existed! I always used a flat iron tip piece on my soldering iron. I really like that jounjip one with the tip that allows you to feed the repair stick through it. Definitely getting one now before the price goes up!
Thank you for sharing!
Wood burning kit at HF has lots of tips and would work great
After having just repaired a car bumper with a couple of cracks in it. I can say that the effectiveness' of the repair is really more about technique than the tools used to achieve it. I bought the Allturn gun with the staples and mesh kit, before this review. Melting the mesh into the base plastic rather than using the plastic sticks to bond it is far more effective. Cleaning and sanding the base plastic is really more for decontaminating it than for for providing a good bond. Melting the base plastic to itself rather than relying on the filler material for the initial bond is also the best. Try to use the filler material as filler, but to also melt the base material into it. The Allturn setup is a really good value at $35 and it works really well. That's the one I would recommend for the occasional plastics repair. It'll pay for itself the first time you use it and it comes with everything you need to tackle many repair jobs.
Thanks for the feedback.
I do plastic welding very often to repair anything that breaks like plastic porch chairs and the grass exit Shute on my riding mower. It is always as strong or stronger than original. I do often use the staples to bond it and make it strong but the major key to plastic welding is to get the plastic melted very deep for maximum penetration. I try to get halfway through the thickness then again halfway through on the other side for complete penetration. even with the staples. and if you use wire mesh it should be melted deep into the plastic and not just stuck on the outside, the welding rods are really only to fill gaps in the plastic that the original plastic leaves as you weld it. Not to put a thin coat over the break as you did. I actually was surprised that it held as much in your tests as it did. But it was interesting to watch. I enjoy all the testing you do and often make my purchases of items based on how well they did in your tests!!
I can smell the smell of burning plastic through the screen haha 😄 great review as always
lol. Great point!
I had a cracked refrigerator door and used a really cheap welder . I used a soldering iron from harbor freight. Still holding 🤞🏻
Nice! Glad it worked!
Wow. I always wondered how good plastic welding worked. I love all the comments and constructive feedback. What a great video idea! And what a great community. Definitely in my top ten UA-cam creators. Thank you!!!!
Thanks and you are welcome!
Awesome stuff. I have a plastic welder, I've used it to repair cracks and breaks in plastic bumper covers a few times. The staples are the way to go for strength for sure. You can make stuff look new again with enough time and other products! haha
Great points! I really like the staples too.
I liked that you included jb weld. It wouldn't of occurred to me to out in a welder review, but it really increases the value of the results. This is why I've watched your videos before making major purchases (drill, generator, chainsaw)
Thanks!
There's one other method of welding plastic components together that I learned as an Airframe and Powerplant mechanic, following the Cessna 152/172 Series Service manuals: Chemical welding.
In essence, take some plastic chips that match the plastic you are trying to fix (don't use Polyethylene on ABS, for instance), and dissolve them in hard solvent (MEK or full strength acetone), best done in a resealable mini can. Mix it up thoroughly, to get a smooth consistency of this now thermoplastic paste. makes sure the repair area is clean, then wipe the area with some of the solvent and let it sit for a minute or two. Then you fill the repair area with your thermoplastic paste like you would using JB weld and let dry. once the solvent evaporates completely, you should wind up with the plastic weld being completely indistinguishable from the base material, but I've never actually put that to the test.
Since you put it into a resealable can, the paste you have made will stay ready to use almost indefinitely, and if it does dry out, just add more solvent.
Thank you for listening to my idea. I did enjoy the video, Though as other people noted, using dissimilar materials when trying to weld some of the plastics did not do you too many favors. There was still really good information on the welders involved.
I'm not the poster, but I appreciate your work commenting. I'm going to research the manual as well.
@@bostonmarketfeministbookclub Working at a flight school, I've done this kind of repair to a few aircraft, always on the non-structural fairings. The Maintenance manual definitely has dissolved thermoplastic bits as an acceptable repair under "Repair of Thermoplastics" in the Structural repair sections of Cessna 152 and Cessna 172 (Pre-R models) Series service manuals.
In our flight school environment, this was almost entirely done for cosmetic reasons. Pilots squawked aircraft all the time because things didn't look right, even if it had zero impact on function or safety. But when pilots don't fly, school doesn't make money.
PF is the must have subscription on UA-cam. Always impressive, Always a money saver with this research.
Thanks and you are welcome!
Some say with the staples, when you penetrate halfway into the material, you twist it slightly to gain more new material to anchor from...kind of like a twist-lock.
I'm motivated to break something to test mine out that way 😁
Thank you for sharing!
I don't do much plastic repair, but I use my Ryobi glue gun a lot, one of their best products.
Thanks for the feedback.
Love watching your experiments you help us buy better products
Thank you!
Wonder if there are even enough labelmakers out there to review!
I was really surprised at how well hot glue with wire mesh did. Seems to me like JB Weld is the most practical solution unless you regularly find yourself needing to weld plastic.
Thanks for the feedback.
I use JB Weld on the pressure side of a radiator inlet that had cracked. That repair outlived the car by 10 years.
JB Weld is a chemical miracle. If it's mixed properly, and the surfaces are cleaned and roughened, and it's allowed to fully cure, it can do almost anything. I score surfaces with a knife blade or the edge of a tiny file, instead of using sandpaper. I feel it gives it a bigger tooth to grab onto, and it seems to work very well. SO glad I found JB Weld.
Just like traditional metal welding, polymer welding has one hell of a learning curve. Ive used hot air and iron style welding and prefer hot air because you have an indicator before everything gets messy.
Great vid. I can see that a decent soldering iron can cover the jobs of any of these, but the iron tip with a hole and triangular shoe looks worth buying / copying. One idea that came to me for testing was multiple buckets to repair so you could pressure test each repair. And with the butt weld test pieces, bevelling the join would really help as would much, much more heat and time before feeding in filler material. It looks like none of them melted into the parent material. The Beyondlife is beyond hopeless, however. It's not you it's him!
Great point! Thank you
I use my soldering iron all the time to fix broken plastic. To make it look great you can file it smooth then hit it with a hot air gun. I use the hot air soldering station I have but any old heat gun would work. Just slightly melt the filed surface and it dries really smooth and does not look too bad.
A temperature controlled soldering iron is better because you can dial in the temperature for the melting point of the plastic you are welded. Heating plastics too high will weaken them.
Part of the issue with bonding plastic is that the heat adds extra carbon, which makes the repair area more brittle on parts that have to flex (motorcycle fairings). You can use a soldering iron or wood burner. V notch you repair on both sides and gently heat the area with directed heat from a heat gun with a nozzle. Tack the parts together at several points. Get a wire screen patch cut, Fill the V notch with plastic, zip ties work well, and embed the mesh making sure to fill the v notch on both sides. Then use JB weld like Bondo to feather the repair on the presentation side. The other side can be left a bit rougher.
When I wad 18 I worked for an auto body shop..specifically I rebuilt plastic bumper covers. We had a few of those hot iron and rod type welders but they never got used. We used a plastic welder that used heated nitrogen to melt these gnarly 1/8” thick x 1” wide strips of some sort of plastic. The strips would go on the inside of the bumper cover and the outside would just get finished cosmetically. That stuff was invincible. You’d tear a new hole in the bumper cover before you pull the repair apart.
Thanks for sharing.
Very interesting. I have quite a bit of gear for plastic welding, but saw some new stuff in there to ramp up my gear lust!
In my own experience, I've found that the first and most important thing is the type of plastic that you're working on. HDPE, ABS, and acrylic are all totally different. For most repairs, I like staples with steel mesh melted into the repair piece, and then additional material over top of that.
Thanks! Thanks for sharing.
hey Todd !! i dont know about dedicated " welders " but I AM A HUUUGE JB FAN. i have done radiators, exhuast pipes and headers. also, intakes, blocks.
and yes ALL KIDS of plastics from dashs to bumpers ..... misc household iems. it sands, fills, drills, tapabilitie, sand it, prime it n paint like bondo !!!!
there r tricks n technigues to work the stuff. 1 is that like REAL welding FULL PENATRATION is paramount !!!!!!! another is learning 2 control how much hardner to use 4 the type of job ur doing..... more flex ..less flex etc !!!!
it is a very versatile material !!!!!
Making battery packs using spot welders are hit and miss. A review of these would be fantastic. Great job with this one, Mr. Farm, always a nice Sunday with a tool review.
Thanks! Thanks for the suggestion.
I'll second this! But there's lots of similar ones on AMZ and even the more expensive ones can have bad reviews either because of actual poor performance or bad technique. It's a tricky subject, perhaps just like the plastic welding test.
I use a simple soldering iron and mix the breaks together going back and forth lengthways completely mixing the two halfs together at the break. Works great for me. Seems like these methods just add stuff to the top and bottom and don't do anything where the two pieces touch.
Great tip! Thank you
I used a cheapo $20 kit a few years ago from Harbor Freight to weld the plastic gas tank on a Honda Element after my wife ran over a tire jack that fell off a truck on the highway. Not going to lie, even with the tank empty due to where the jack ripped into the tank, it was a scary process but it did work and it held for over a year while I had the vehicle before trading it in. I used wire mesh when I did the weld. Prior to having the Element towed 40 miles, I didn't even know plastic welders existed. This video definitely shows there are some much nicer options!
Thanks for sharing.
Something I've noticed is the method of sanding that you use is in only a single direction and that is hurting the overall strength of your repairs. When sanding you should always use a cross method. The idea is to provide the most surface area possible. You should be able to see little crosses in your sanding grooves. You will be surprised at the difference it will make. Also I noticed that you are a little impatient with your iron give yourself a little more time starting out to sink the tip into the parent material. Just like with normal welding you gotta get penetration. It's not like hot glue. You have to make both half's into a state of matter that is borderline molten in order to achieve fusion.
It would be really interesting how acetone solvent welding holds up in comparison on the ABS and polycarbonate parts!
Thank you for sharing!
I bought 2 of them recently and used them right away to fix one of our large recycling bins. The Allturn is definitely one to go with. If you do it carefully and if conditions are just right, you may not even need to use the "sacrificial" plastic sticks to build up the plastic. You will want to use a Dremel sanding tool drop the height of the metal clip ends once they are embedded. Be careful about the temperature of the Allturn and how you handle it or where you put it to cool down because it is quite hot once used. I also bought the Harbor Freight one that looks like the Joonjip which seems fine for small areas but the Allturn was flexible with the items you can fix with it, it was fast, and seems effective.
Thanks for sharing.
Todd is the hero we NEED, but don't DESERVE.
Lean new things with every video you release.
Love ALL of your videos, man!
Thanks so much!
@@ProjectFarm No biggie lol
Tip I picked up: You can chuck a short piece of 3d printer filament into a Dremel tool and use that as a stir welder. Works pretty well with some practice. Use the same type of plastic filament as the part you're repairing.
Thanks for the tip.
Didn’t Fran Blanche do a video showing some old plastic stir welding device that worked just like that?
Either way, great tip about using 3D printer filament. I’ll have to try that sometime!
I have done the staple trick with a torch... Additionally, melting the mesh INTO the plastic, I believe, is how it is meant to be used...
Not how you plastic weld, you use the tip to melt the plastic together then fill if needed with more material. Try and use the same material, however the fiberflex works really good.
Thanks for the constructive feedback
@@ProjectFarm No problem, now I might have to do a how to video with my plastic welder...LOL You kept that tip off the base material, you need the base materiel to melt to bond The head with the feeder hole you put the head on the base material so that melts and you push in some new material through the hole. Maybe this is just an art and I have done it a LOT...best investment on the Polyvance I have ever made.
What i noticed was that on the polycarbonate you weren't using the appropriate weld stick. It needs to match the type of plastic you are working with. That's why they all separated on the polycarbonate.
Great constructive feedback. Thank you
The same goes for HDPE. It won't bond to other plastics, only HDPE AND LDPE.
Sad when YouTUBers show knowledge but have no idea what they doing.
Cheap plastic weld kits probably come with limited types of weld sticks. I feel that his tests are supposed to simulate the use of what comes in the kit, not specialized items you can buy. If some one wants to repair plastic they should do research to understand how to make proper repairs. Plastic is harder than stick welding. This channel is not to teach you to be a master stick/mig or Tig welder or to teach you how to repair plastic. Just to review products. He does a fine job on that.
@@mikga45
Yes a fine job. I learn from the comments as well as the video.
Excellent tests! Out of necessity, I've repaired several plastic items, mainly with a 140v/100v weller soldering gun. As others have mentioned, I've had better luck heating the screen directly into the original piece & using minimal filler.
Great content & thanks!
Thanks!
Loved this video!!
A very common problem is cracked gas tanks. Perhaps you could use the plastic welding kits you already have and see which works best on cracked plastic gas tanks. If you do please be sure to use a new tank or one you have cleaned and are sure no gas fumes are present. Thank you
Thanks! Thanks for the suggestion.
0:26 "they claim it can be used to repair a dashboard".... I'd hate to see what that "repair" would look like! 😂
lol. Great point!
I worked at a plastic Fabricating company for many years. We built polypropylene water tanks for fire trucks. We used Laramy hand welders and Munsch extrusion welders
Thanks for sharing.
Can confirm. I have the Jounjip AND the Allturn for the staples. I've learned you need both, they complement one another. And you do indeed need a lot of practice. Last tip is to make sure you get the same weld rods as the plastic you're repairing.
Thanks for the feedback.
I'm surprised you didn't try acetone - it's a great option for certain plastics when you can't use heat. Being practically as viscous as water, it penetrates deep.
Very good, but terrible for polyethylene and polypropylene
I just purchased the Jounjip plastic welder (sight unseen) literally 60 seconds after viewing this video. I used one (with transformer in box) decades ago and the wire mesh held up fine. Too bad you couldn't torture a tool into extinction this time, but I still always enjoy your videos! I've made many purchases over the years based on your recommendations alone..
Thanks! Thanks for sharing.
Could I request best electric pencil sharpener? Teachers are struggling with poorly made products. Compare them with cheap/expensive pencils and to the old crank sharpener in most classrooms still
Thank you for the video idea!
Try some ABS pipe glue, I find it to work really good.
Thanks for the tip!
Excellent tests. The staples are great for tensile strength and work better if you twist them once sunk into the plastic. I was really surprised the Ryobi glue gun did so well comparatively.
Thanks for the video
Amazing video as always! Thanks for helping us to make better informed purchases!
Happy to help!
Would have been interesting to see a soldering iron in the mix. Really I’m not seeing much of a difference except the tip shape. Maybe max temp?
Great suggestion! Thank you
The classic Weller and Archer soldering guns (not irons) had paddle tips available specifically for smoothing and mending cracks in plastic.
@@goodun2974 that’s pretty cool. Thank you for the information.
Big tips, so probably more thermal mass. Bu a lot can be done with just a regular soldering iron.
Those with experience say just enough to get a semi liquid surface but never hot enough to burn or run out.
Love your videos, they all help me very much on what to buy and what not to buy! Thank you!!!
Thanks and you are welcome! Glad to hear!
Would've loved to see Sci-Grip on this list. Making an ABS or Acrylic slurry for adhesive is like magic.
The hot glue did a better job than I expected.
Agree. I doubt it would last long from continuous water exposure, but it does make a great temporary repair.
@@ProjectFarm all glue fails on pe after some time, the only thing that works on pe is pe. Did plastic welding for some years, and the joke was always to invent a glue for pe and retire of the monney
Hot glue is fine at more or less room temperature but get it up to 95 or 100° or more and it will start to soften. A friend of mine hotglued new speakers into the dash of his Saab 900, onto the mounting plates that sit under the corners of the windshield, where the sun would beat down on the dash, and as soon as we had a hot day the speakers fell off the mounting plates.
@@ProjectFarm Which brand of hot glue did you use?
Sorin from electronics repair school uses it to repair broken hinges of laptops. I wouln't expect it to hold, but it does.
Thanks for the testing. your tests more or less confirm my experiences repairing plastic which is that it is for the most part a waste of time in applications that require strength. Once those molecular bonds are broken not much short of sonic welding does much more than disappoints you when the part breaks again. Plastic has replaced a lot of items that used to be made of metal, it is not much fun to work with when it breaks, and regardless of the amount of plastic in the part is generally very expensive to replace something that if made out of most metals would have been easier to repair or wouldn't have broken in the first place.
I just used JB weld original on a plastic housing that covered the intake end of a diesel air filter. There were 3 cutouts on the end that could flex a little to slide over the filter. All 3 places had cracked. I sanded and cleaned the areas then applied Original JB Weld along the crack opening the crack some so that some glue got into the crack then applied more glue all over the outside of the crack. upon installation one of the sites re cracked. It was on the intake side so that the air was still filtered so have not gone back to reseal it. The filter has to be loosened from underneath but the only way that it can come out is out the top of the engine after some of the inter-cooler piping and other things have been removed. Not fun and really not much of a problem.
One product that I have had limited good luck is Seal-All. I have a 1984 Toyota Corolla that runs on diesel. It developed a very slight leak in the fuel tank. As a temporary repair I used Seal-All on the spot without draining the fuel. At the time it recommended that I use a single thickness of cardboard like a heavy end flap of a box lid or the cardboard backing of a note pad placed over the Seal-All and held in place for a short period of time. I did that temporary repair over 20 years ago and it hasn't leaked yet.
You are welcome! Thanks for sharing.
Glad to see I'm not the only one who struggles to make plastic welding look like something other than snot bubbles :D
LOL...I'm doing well to make my MIG welding look like anything other than snot bubbles 😆
The Beyond Life one is a design used for heat welding vinyl and linoleum flooring. It requires a beveled grove, like welding steel. You use the hot air to heat both the parent and filler materials to just shy of liquid and press the rod in with the tip. There's definitely a learning curve and it's kind of becoming a lost art. Next time you're in a hospital, look at the vinyl floors, every 6ft you'll see the weld joint.
6ft surely you mean 2m.
This was a fun video. I got the harbor freight plastic welder, and with a little practice and patience I’ve managed to make some fairly decent repairs. What I found worked the best was using the triangle tip to gouge out a channel into the crack or split, and then using filler material to join the two pieces. I let one side cool and then repeat the process in the other side, if I can get to it. then build it back up over the surface so I can buff it back down with a scotch wheel.
Thanks! Thanks for sharing.
Super glue and baking soda also bonds really, really well.
Great tip!
I was committed to buying a new headlight bucket for my 240 Volvo, but I figured since I had it out anyway, why not try to fix it (I hadn't found one yet). I used fresh super glue (cheap), and finished it off with baking soda. I was pleasantly surprised to see the shattered plastic (three pieces) all went together and held up under light flexing (stress they shouldn't be exposed to in real life). I did fill some of the cavities in the reverse side with epoxy, since I had it on hand.
Has held up so well, that when I finally did find the correct part, I passed it up.
In other applications, I've dusted one side of the break with baking soda, and applied CA glue to the other part. Instant, strong bond.
The weekly content never ceases to amaze me-week in/week out everything applies to our day-to-day needs on a genuine/useful level. Thanks Todd. God bless.
Btw, I love hearing you say: *"Made In The USA."* It's good to know we're cranking out more than potato chips, SNL skits, and corrupt politicians. 😳
Thanks!
I’m at the point that I will pretty much pay double for some thing if it’s made in the US knowing that I’m providing work locally, have a good customer service, and the product people will stand behind. I needed a screw for a Leatherman tread that I couldn’t find anywhere and simply called the company that’s local in the San Francisco Bay area. I was shocked when someone who spoke English answered their phone and sent me the screw in the mail No charge. Would be a great video of you highlighting companies that do this(even if some of them do have components built in other countries)
I got my first plastic welder 2 weeks ago, the "Sonnler" SN-B150, it looks exactly like the Altern , but speced at 150 watts power, the staples will get Red Hot in seconds, I've been repairing broken Motorcycle body parts , battery tray, rear fender, side panels etc. The squilly shaped staples give more support than the straight ones, i find it important to let the staple and plastic cool , before removing the welder from the item being repaired, to prevent pulling the hot staple out of the repair , also on your bucket, i would have used the squilly Staples , and put them length wise on the cut, using two or more not just one straight one across the cut, your cuts simulated a stress break, and should be supported across the complete break, you are always very thorough in your testing, but i don't think the breaking test reflected real world experience, as most plastic is either broken by impact, or by repeated stress such as vibration or repeated flexing, i don't expecting my plastic weld repair to be as strong as the original factory new, i just want it to hold together and extend the life of my motorcycle or generator or patio chair etc, seal my bucket until i buy a new one, repair a cordless tool storage box etc..
The reason you had problems using the hot air welder is you set the temperature way too high. You need to set it high enough to melt the substrate and rod but not melt either one to liquid form. For HDPE I would probably set it to 325 to 375 F. For thicker materials you can got higher.
If used properly, the gun will melt the contact area of substrate and rod, creating the weld bond.
I’ve used this type of gun for a lot of welding HDPE, PVC, ABS, PP with great results both for physical strength and water tight containers.
It does require more skill and practice than the hot iron methods but the results are much cleaner. Not what you experienced.
i wonder if alternating the staples from both side of the break would make a difference
It seems some would have done better if the base material was melted along with the filler material, so they create a good bond.
Great point! Thank you
FYI I use hot air guns and hot glue guns for a living, the Beyondlife type hot air gun is not for glue sticks, they are specific for poly ethylene or similar welding rods and they work great for building and repairs of rotomolded pieces. Not for plastic buckets . also when welding the two HDPE square rods together ya really botched that up. the objective is to melt both ends then force them together, wait till it cools off about a minute, release pressure, then wait for complete cooling... now you essentially have one rod. it would have been the strongest test result.
Do a video captain, so we can learn
I can make a video...but i never uploaded guess i could try. @@TheRoadhammer379
I really like the crafty way you come up with to do all these tests, Great Video, THANKS
Feeding the algorithm
Thank you!! It's a hungry machine that requires a lot of feed. lol
Got one for you, buddy! Soil testers - there's a huge amount of these sold on amazon and elsewhere but nearly NOTHING online about the quality, accuracy, or longterm reliability of these. I notice in some reviews that you just abrasively clean the contacts/sensors frequently, some mention how deep it needs to go to get a good reading, others mention how much prep into the soil is needed to get a good reading (watering, tilling, etc). Plus I'd really like to see how accurate they are compared to a lab test.
Since you're a farmer I bet you've got great thoughts on this too. Hope to see this one soon!