I used to get to plug weld 1/4 panels on with brass back in the 70`s. I always loved brazing, and because it is an adhesive bonding process, it is super strong. Taking panels off that had been brazed on had to be done with heat too. Now we use mig plug welds or just bond the panels with epoxy. The body and fender trade has changed so much in 50 years. Super cool video. Cheers
I know when gas welding steel it is important that you use a neutral flame and I assume that is what you are using also for brazing. You may have mentined this in the past but it may bear repeating the type of oxy flames you can use for different type applications i.e. carbon rich, oxygen rich or neutral. I really enjoy you approach on your videos as being realistic (not cutting out the mistakes and mishaps). Thanks for being an inspiration.
Good to see you do this thing. I did service for stoves and they most of the time had cast iron trays on them for the pans. Sometimes people dropped them and I had no idea that they could be repaired. Goed gedaan ouwe Rucker!
Perfect timing! I have a broken casting myself to fix, and i needed a refresher. Funnily enough i was going to watch another of your older videos. You read my mind Keith. :))
My father taught me how to Braze weld, when I was a teenager. years went by and never used the welding technique. Then when I had to my father had passed, so I came and took Keiths "class" To this day that John deere bucket mounting bracket is still in use, and the tab hasn't moved. Thanks for the tips keith.
You should get some flux powder, if there is some trouble with bronze not melting to base metal, dumping a spoon full of powder flux usually helps. Hate those pre fluxed brazing wire, never enough flux for my liking, flux powder, the good one with plenty of fluoride, always helps! Some backing shim, like 0.3mm steel sheet might have helped here too, to keep the bronze puddle in place.
One thing I was taught in trade school was that when brazing cast iron, the cast iron is dirty due to graphite in the metal and the flux on the rod is not enough to clean it for proper brazing. we were given a can of flux and were told to dip the rod into as we brazed to bring in extra flux.
@@ellieprice363 Borax still is used as a flux. I pointed this out to RotarySMP and he replied that borax is not readily available in Europe, as he was looking for flux also.
@@millwrightrick1 Here in Spain you can find it labeled as various kinds of brazing flux (some have specific additives for specific metals) at most plumber stores, hardware stores, car parts stores and of course welding supplies, I guess on other European countries it must be more or less the same. Turkiye (it's now the official name in English for Turkey, to differentiate it from the bird eaten at Thanksgiving dinner) is the largest producer on this side of the pond, every year they extract more or less the same amount as the entire United States so I guess they make enough for Europe, unless China buys it all 🙄
Thank you for sharing your experience and intellectual capital Keith. Intellectual capital is what lawyers do their best to monetise. You are a good man and an exceptional teacher. You have much to be proud of.
Every one of my flame braze cast iron repairs using flux coated bronze has been a success when I cleaned and ground out the cracks before starting but I can’t say the same for my cast iron welds. Like any repair preparation and environment play HEAVILY into the results you will achieve. I usually spray the pieces with water to minimize cross contamination and prevent embedding dirt and oil while using a carbide to cut open the crack. For heat up, I start with a propane torch (burns relatively cooler which in turn takes longer minimizing stresses in heat up before turning to my oxy-acetylene). For cool down, I keep a large plastic storage tub filled 1/3 with pre-washed white sand and it has been a lifesaver for tossing the smoking hot piece into for burying. A large well insulated fire blanket like Keith used is also a good choice. Slow heat up and cool down are critical for success which makes it not viable when a quick repair is needed so I believe it’s not about one method being better than the other but more about using the right technique for the job’s specific requirements. If you are crunched for time and work flow is dependent on a part getting finished then absolutely grab a nickel rod and weld that puppy back together, however if you have flexibility (assuming identical prep), I do believe that between a successful cast iron weld and a flame brazed repair, the brazed repair will still be superior in durability however marginal it might be [can’t speak to TIG brazed since I have no experience w/ it]
@@markbernier8434It is doubtful the center to center distance is crucial. If you understand where this part goes on the drill press, even being off a couple hundred thou shouldn’t be a big issue. I doubt it’s off more than one hundred thou.
@@markbernier8434Center to center distance is less important than the outboard surface that the table will be mounted to. This surface must be square with the main column bore for the table to be level for drilling.
It's going to be square/parallel*, but it isn't going to be exactly the same distance to centres. *assuming the two flat machined surfaces are correct.
Another great video Thanks Keith.If I may add my experience the steel table is acting like a HUGH heat sync. I use a brick or cement block . Again love the videos.
Always good to see you get the torch out, Keith. I used to do quite a bit of torch brazing and got great results. It's an underappreciated process that requires patience and finesse. You demonstrate and explain brazing with great clarity, thanks! I don't think most people realize how strong and hard bronze is, as opposed to brass, which is relatively soft and not used for brazing. Keep up the good work!
In the land speed racing world a car crashed going very very fast and the driver walked away. I met the man that built the frame. He said the frame was all braised steel and it did not have any problems crashing and rolling seven times.
Sometimes you can get a stronger braze then a weld in steel depending on the part and joint you are dealing with! Not to mention weve been making copper alloys well, since the bronze age we do in fact have some that are stronger then steel when the need arises. Ive used them, and they work wonders. But for cast iron I fully agree brazing is almost always the best choice. I dont speak in absolutes because there has to be some exception I am unaware of. But almost always the way to go for sure
Controlling the heat while brazing. Our welding instructor had his way of teaching us how to recognize what the metal being brazed looked like. He had gone to the auto salvage yard and used a hammer to break up cast auto grills that were Pot-Metal. We had to use the Oxy-Acetylene torch and some pot metal rod to fuse two pieces back together. A dab too much heat and the pot metal would simply fall out. Once we learned to watch for the change in the surface appearance of the pieces to be welded and then by control of the flame application to melt the rod to the "Sweating" metal pieces a passable braze would amount to passing the test. I still like to flame-weld metal together. The only problem is that metal coathangers for welding rods are a thing of the past.
Welding on sheet metal meant, welding, using a hammer and dolly to flatten the metal, and welding some more. Heating a panel and hitting it with a wet rag to shrink a high spot. One of the fun things was using lead as a filler. Heat a bit, apply acid, heat a little more, take a lead bar, melt some onto the panel, and use a wooden paddle to spread and shape it. It is a wonder any of us old guys survived. At least the lead made a more permanent filler.@@alfredocuomo1546
I have a Cole vise that was split across the base of the anvil from abuse. I was able to "V" it inside and out and then preheated it with my propane weed burner. I set it up on fire brick and went at it with my brazing torch and Bronze flux rod. It brazed up beautifully and has held up well for several years now.
Hi Keith, I love your videos and have followed your channel for several years. I would love that you made a video about how you set your acetylen and oxygen before welding❤
Hi Keith. Great video, been awhile since I’ve done any brazing. Great reminder. On another note, you gave a teaser a couple of weeks ago about building some wedge style footing/leveling blocks for the big Monarch Lathe. I’ve recently acquired a 100 year old K&T Model B horizontal mill. For several reasons I can’t use a traditional screw type leveler. When can we expect to see this video? Thanks.
It worked better after initial heating when you turned the flame down a bit. I'm surprised you never had additional flux to hand, I'm sure that would have been a boon too.
Good to see some extra brazing added to the side act as a splint. The worry with cast iron seems to be "why did it break in the first place?" The original casting seems a bit thin given the load that could be applied to it.
If you upgrade the kitchen tabletop toaster oven - glass door etc. Good to use for rods and metal. Dial and use a internal thermometer just until you trust the dial. They work great. Simple and large.
I've had fantastic success doing old school oxy-acetylene flame welding cast iron with pure cast iron rods and powdered flux, but it requires the entire part is kept cherry red the whole time using a contained fire of some sort on the whole part. Then very slowly cooled like you did. However, I would love if there was a braze that color matched really well, then I might switch to that method to avoid having to make a contained fire each time.
My only suggestion is to put the parts to be brazed on a surface that is not a heat sink. Fire bricks or refractory tiles laid on the table would keep the heat in the parts rather than being drawn away by the steel surface.
Nice job! I liked the idea of using shims to keep the machined surfaces coplanar. I'm just wondering if you could get a few thin insulating shims to serve as heat-loss barriers. Then you could use ordinary metallic shims to set the total shim thickness. I don't even know if insulating ceramics are available at a reasonable cost or whether or not they would be durable enough for shop use.
I would have suggested an inexpensive fire-brick under it. Probably could have saved some gas, but it obviously worked out well enough even with the steel table.
@@TheFreshmanWIT , I thought of firebrick but I'm not a welder and don't know how porous it is. Here, however, the casting has two machined coplanar surfaces about 2cm apart in height. So, is there some sort of "foamy" ceramic that might be available in a thin sheet? The stuff they make spacecraft heat tiles out of would be perfect, but most likely horrifically expensive.
@@stuartschaffner9744 You could probably use a ceramic tile as well, but a firebrick is usually pretty darn flat and he could have put the same shims on it. It wouldn't have prevented THOSE from getting hot, but at least the giant steel tabable.
The only braze joint I've ever had fail was a prototype recumbant bicycle frame I built about 1982. The joint that broken was unreinforced and high stress, and I was using a weird pellet gas system at the time, so gas/heat was not optimal. At that point I realized I needed a real torch, and bought an oxy/acety kit the same week that I've been using ever since. I've actually had welded butt joints fail that worked just fine when brazed.
I'll say it again, our family farm has equipment that my grandfather and father brazed 60 years or more ago and it's still working just fine. A good braze is as strong or stronger than the original metal.
I'm curious how much brazing steel is from brazing cast iron in terms of difficulty. I've done both, but under different circumstances. During my college welding course we brazed steel, and after many hours of practice, most of us were able to make it look like a tig weld. When I've repaired cast iron, I didn't have an opportunity to practice for hours adjusting my torch settings before making the repair. With cast iron it seems like it wants to run everywhere and puddle up. The steel brazing we did in college wasn't just a superficial pretty bead layed down. It was two steel coupons brazed together, cut into strips, and the had a bend test done on them. So, I'm asking if there is anyone with experience in both that can tell me the difference in difficulty there is between the two.
Putting numbers to what Keith said; A structural welding rod like 7018 has a tensile strength of 70,000 psi. Harris lists their RBCuZn-C which is a bronze brazing rod as up to 65,000 psi.
Well unless he is going to be hammering on the drill press table I think the 10k psi will be more than sufficient for normal drill press usage. when it comes to parts like that I agree that oxyacetylene welding is better than TIG welding for the more uniform heating of the cast and the slow cool down is critical or you will create stress cracks and further damage the part. Nice job & good video.
Me, too. Surprised that a jig or clamps weren't used to keep the 2 machined surfaces in the same plane - especially since he mentioned it being an issue with the earlier attempt.
You do have an oven to preheat. Your heat treat oven which is fully programmable for temperature and time. And it appears to me the part is small enough to fit inside, and it would most certainly do a better job than the torch, because you said yourself that you want to heat it evenly.
Wouldn't he have to reheat anyway after removal from the oven? By the time he got it out of the oven and setup to braze, it would cool a bit...unevenly. The torch heating was a couple of minutes. The oven would take a while.
I'd say it comes down to what is the most practical process for the job that you are doing. I have a bad habit of turning five minute projects in to a career. Keith shows me how to find a balance.
@@oleran4569 When doing jobs like that, you setup everything ahead of time. What,15 to 20 seconds from the oven to the table, plus he could heat it about 20 to 40 degrees hotter to allow for transfer time. By the time he adjusted the torch from heating to brazing, it's a wash.
The broken parts are easier to set up in position when cold. The torch is a very fast and portable heating source that preheats the part much faster than an oven. No need to use an oven on a part this small.
Maybe I ask a silly question but… is there a significance of using a stainless steel wire brush rather than a ferrous steel wire brush for cleaning things as you go along.
can't quite say, but it looked like flux was bubbling out from the edge of the metal, almost like it wasn't hot enough when it was originally brazed. might have just been a reflection.
these rough castings are much cheaper chemistry. i prefer brazing like this most of the time but i have use nickle rods but the castiron needs to be really high quality.
Yo Keith, You have to be the king of brazing cast iron but I take issue with saying welding makes the repair weaker. We have been doing virtually undetectable repairs in cat iron sine 1980 using OXY-FUEL WELDING. We have done many repairs on antique furniture (Even pre-civil war) that after shot blasting and needle scaling look like it never happened. -And for stringth and mahinability, how 'bout the frame of a 100 ton punh press? (Even had Harris custom build water cooled torches for us) I will say between you and Abom I hae started using TIG Si, Phospher, and Aluminmum Bronze for gear tooh repairs (depending on how dirty they are) I still say gas welding with cast iron rod ,,,,,,whih ampunts to selective re-casting ---- is the only way to truly repair cast iron. ------ Hey, I do 1000% agree Ni-Rod, and stainless is nothing more then camoflage and only mak a bad situation worse, but I'll tik to gas weld with real gray at iron rod for critial appliations. And for the record- for the this appliation your way was 100% in my book.
Totally cheeky question, Keith: I notice the number "1582" on your worktable. Does this number have any particular significance? For instance, your year of birth or something equally important?😈😈😈 Sorry.
You should pick up a couple of porcelain tiles for $4-5 at the store and put them under your work to prevent excessive heat leaching. Most are good for 2000f. Not an expert compared to you certainly, but seems like it would make a lot of sense to insure that giant piece on the right is really hot before starting brazing as its got a larger surface area and mass and will suck the heat out of the smaller part and dissipate it much more rapidly when done, leading to internal stress/fracturing? Might not really matter here, however seems like relatively simple tweaks which should lead to slightly better results for 4-5 minutes time.
Please or offend, but the truth is better to be shared than ignored, right, Keith? Some viewers who watch this type of video are looking for more than entertainment. They want help, advice, and even a lesson on how to best deal with a situation they themselves are experiencing. What I am about to say is not meant to hurt or offend anyone, especially Keith. But from time to time, we see things that need to be rectified. We, as in, time served professionals, on occasion see things we know through experience, are wrong, and todays video is one such occasion. We owe it to ourselves to put things right. I've been a qualified fabricator welder and engineer for more than 40 years. Through hard work and late nights, even weekends, I now have 3 apprenticeships under my belt. I cut my teeth on oxygen acetylene gas and stick welding in the 1970s. The best, the only real successful way to fuse broken cast iron parts together is brazing, using gas, not a Tig welder. Now, Keith, I know you are a good knowledgeable engineer and may well have brazed hundreds of cast iron parts over the years, but something I have noticed, we'll, there are two things, really. First is your technique. With practice, and you must have had plenty of it over the years, comes finess. Practice means perfect as the saying goes. Over the past year, almost every brasing job you have done, Keith has been somewhat sloppy. I'm sorry to say that, but it's true. You've gone from adding way too much filler rod, so much that it flowed over the project piece, in effect, wasting filler rod and gas. To then go the complete opposite, by not using enough filler rod. Over the years, you would have experienced that flux fills up voids unless you have your object and the nozel tip at the right angles. As you quite rightly pointed out, flux turns to a glass like substance. There is no way to stop that from happening. Flux, for those viewers who do not know, is a substance, usually an oxide, which is used in many things such as glass making, for example. To lower the high melting point of the main glass, which forms constituents like silica and alumina. In layman's terms, it's a form of purification. Fluxes are substances that are also used in glazes and ceramics as in pottery for the same purpose. That's why brazing flux turns to glass. Now we understand what flux is and what it does. Flux glass can give the illusion of a good, strong weld, a fools weld. That is why you are meant to tap the brazed joint or filler. In fact, you should tap ALL welding joints with a welders chipping hammer. The second most important tool in a welders bag. These specialist hammers are used to remove flux and welding slag for two reasons. The first is to check that you have made a good weld. The second is to allow further welding to continue along the welding line or allow further welds to be placed directly on top for the same reason, as in mig or stick welding, which is common place. Not to be confused with a wire brush, is that any novice welder knows, wire brushes with wooden or plastic handles are no substitute for a welders chipping hammer! They can not remove flux glass or slag like a chipping hammer can. The last observation I want to address is that of the finished product. As can be seen with the latest brazing project, your finishing is not of good quality or high standard. If I were a paying customer, I would teturn the drill press platform bracket and demand that a better job be done. In effect, starting over. Your attention to surface grinding is of a low standard. I appreciate that most of the repaired portion will be out of sight, but that does not excuse poor workmanship. You should have paid more attention to grinding and sanding away much more of the braze overflow than you did. What is showing gives the illusion that the weld is weak and unfinished. The inside of the bracket does not matter, but the part everyone can see, as seen in your closing shot with the part in your hand. That area should be roughly the same level or flatness as the bracket itself. When you showed us the bracket at the beginning of this video, we could see the previous weld was nice and smooth on the outside, as it should be. The inside was rough, uneven with blobs, which is acceptable. We could also see and hear you say that the break had come away probably because the bracket was not evenly heated up prior to welding. In fact, there are any number of reasons for that break happening. In conclusion: Providing you grind all edges to be welded at the correct or as near as correct angle, possible in the shape of a V. Heat up all parts evenly and the parts to be welded to a cherry red colour. Place cast iron parts at the right angle, which, if done right, will allow a good weld pool to flow. Have your nozel at the right angle, which, when correct, will allow the purfect flow of molten rod to adhere to both sides of the cast iron. There should be no more than 1 to 2 mm of excess braze to be ground, then filed away to a smooth finish. It sounds difficult but far from it when you know how. My advice for anyone wanting to learn how to achieve the best braze weld possible. First, watch several UA-cam videos to get a different perspective from different welders techniques. Then, practice welding two pieces of steel together. Grind away the excess filler and finally file smooth eith a file chisel.or sanding disk. Then, put the piece in a vice and bend it 45° then another 5°and another. See how tough your weld is before it breaks. Look at the break and see if there are any voids or flux glass. If there are any you will be ble to tell the difference between them. Then start again. Grind both parts clean and weld. Bend, snap, and clean. Rince and repeat again and again until you are happy with your welds. It may take you a day, a weekend, a week but don't despair. Like with most things in life, you will get there with dedication and hard work.
Man, I don't know how many times I've watched Keith braze a broken casting. He makes it look so easy, I can assure you that it is not lol.
I used to get to plug weld 1/4 panels on with brass back in the 70`s. I always loved brazing, and because it is an adhesive bonding process, it is super strong. Taking panels off that had been brazed on had to be done with heat too. Now we use mig plug welds or just bond the panels with epoxy. The body and fender trade has changed so much in 50 years.
Super cool video.
Cheers
I know when gas welding steel it is important that you use a neutral flame and I assume that is what you are using also for brazing. You may have mentined this in the past but it may bear repeating the type of oxy flames you can use for different type applications i.e. carbon rich, oxygen rich or neutral. I really enjoy you approach on your videos as being realistic (not cutting out the mistakes and mishaps). Thanks for being an inspiration.
Good to see you do this thing. I did service for stoves and they most of the time had cast iron trays on them for the pans. Sometimes people dropped them and I had no idea that they could be repaired. Goed gedaan ouwe Rucker!
Perfect timing! I have a broken casting myself to fix, and i needed a refresher. Funnily enough i was going to watch another of your older videos. You read my mind Keith. :))
My father taught me how to Braze weld, when I was a teenager. years went by and never used the welding technique. Then when I had to my father had passed, so I came and took Keiths "class" To this day that John deere bucket mounting bracket is still in use, and the tab hasn't moved. Thanks for the tips keith.
Good job Keith. You make that look pretty easy. From experience, I can say it's a lot harder than you make it look!
You should get some flux powder, if there is some trouble with bronze not melting to base metal, dumping a spoon full of powder flux usually helps.
Hate those pre fluxed brazing wire, never enough flux for my liking, flux powder, the good one with plenty of fluoride, always helps!
Some backing shim, like 0.3mm steel sheet might have helped here too, to keep the bronze puddle in place.
One thing I was taught in trade school was that when brazing cast iron, the cast iron is dirty due to graphite in the metal and the flux on the rod is not enough to clean it for proper brazing. we were given a can of flux and were told to dip the rod into as we brazed to bring in extra flux.
A popular brand of flux powder that welders used to use was “Twenty Mule Team Borax”
@@ellieprice363 Borax still is used as a flux. I pointed this out to RotarySMP and he replied that borax is not readily available in Europe, as he was looking for flux also.
wow in whole Europe?, I'm in Poland and borax is readily available
@@millwrightrick1 Here in Spain you can find it labeled as various kinds of brazing flux (some have specific additives for specific metals) at most plumber stores, hardware stores, car parts stores and of course welding supplies, I guess on other European countries it must be more or less the same.
Turkiye (it's now the official name in English for Turkey, to differentiate it from the bird eaten at Thanksgiving dinner) is the largest producer on this side of the pond, every year they extract more or less the same amount as the entire United States so I guess they make enough for Europe, unless China buys it all 🙄
I appreciate the running commentary on what you are doing and why
Thank you for sharing your experience and intellectual capital Keith.
Intellectual capital is what lawyers do their best to monetise.
You are a good man and an exceptional teacher.
You have much to be proud of.
Every one of my flame braze cast iron repairs using flux coated bronze has been a success when I cleaned and ground out the cracks before starting but I can’t say the same for my cast iron welds.
Like any repair preparation and environment play HEAVILY into the results you will achieve. I usually spray the pieces with water to minimize cross contamination and prevent embedding dirt and oil while using a carbide to cut open the crack. For heat up, I start with a propane torch (burns relatively cooler which in turn takes longer minimizing stresses in heat up before turning to my oxy-acetylene). For cool down, I keep a large plastic storage tub filled 1/3 with pre-washed white sand and it has been a lifesaver for tossing the smoking hot piece into for burying. A large well insulated fire blanket like Keith used is also a good choice.
Slow heat up and cool down are critical for success which makes it not viable when a quick repair is needed so I believe it’s not about one method being better than the other but more about using the right technique for the job’s specific requirements.
If you are crunched for time and work flow is dependent on a part getting finished then absolutely grab a nickel rod and weld that puppy back together, however if you have flexibility (assuming identical prep), I do believe that between a successful cast iron weld and a flame brazed repair, the brazed repair will still be superior in durability however marginal it might be [can’t speak to TIG brazed since I have no experience w/ it]
I always enjoy watching you braze cast iron.
Looks nice and strong. Would be intersting to see if you check it for squareness and parallelism after though
Also centre to centre distance.
@@markbernier8434It is doubtful the center to center distance is crucial. If you understand where this part goes on the drill press, even being off a couple hundred thou shouldn’t be a big issue. I doubt it’s off more than one hundred thou.
@@markbernier8434Center to center distance is less important than the outboard surface that the table will be mounted to. This surface must be square with the main column bore for the table to be level for drilling.
It's going to be square/parallel*, but it isn't going to be exactly the same distance to centres.
*assuming the two flat machined surfaces are correct.
It's good enough for it's purpose.
I love brazing and welding with a torch. On thinner stuff I use silver solder,
Another great video Thanks Keith.If I may add my experience the steel table is acting like a HUGH heat sync. I use a brick or cement block . Again love the videos.
This just popped up in my feed. I need to fix a rotorary table. I'm going to try this weekend. Thanks. I just have some cracks to fix.
Always good to see you get the torch out, Keith. I used to do quite a bit of torch brazing and got great results. It's an underappreciated process that requires patience and finesse. You demonstrate and explain brazing with great clarity, thanks! I don't think most people realize how strong and hard bronze is, as opposed to brass, which is relatively soft and not used for brazing. Keep up the good work!
In the land speed racing world a car crashed going very very fast and the driver walked away. I met the man that built the frame. He said the frame was all braised steel and it did not have any problems crashing and rolling seven times.
Sometimes you can get a stronger braze then a weld in steel depending on the part and joint you are dealing with!
Not to mention weve been making copper alloys well, since the bronze age we do in fact have some that are stronger then steel when the need arises. Ive used them, and they work wonders.
But for cast iron I fully agree brazing is almost always the best choice. I dont speak in absolutes because there has to be some exception I am unaware of. But almost always the way to go for sure
Happy Monday Georgia! 😊
Good morning Keith! Your videos are always a great way to start the week. Thanks.
Keith you remind me of my industrial arts teacher from back in the 90s
Thanks Keith. I'm curious as to what number brazing tip you were using there.
Nice job Keith. 👍👍
I agree brazing was the best option for this part.
Should last for many years.
Thanks for sharing the process.
You do make it look easy Keith
Controlling the heat while brazing. Our welding instructor had his way of teaching us how to recognize what the metal being brazed looked like. He had gone to the auto salvage yard and used a hammer to break up cast auto grills that were Pot-Metal. We had to use the Oxy-Acetylene torch and some pot metal rod to fuse two pieces back together. A dab too much heat and the pot metal would simply fall out. Once we learned to watch for the change in the surface appearance of the pieces to be welded and then by control of the flame application to melt the rod to the "Sweating" metal pieces a passable braze would amount to passing the test. I still like to flame-weld metal together. The only problem is that metal coathangers for welding rods are a thing of the past.
Now I know your like me a little on the older side, lol that's what all my buddies ever used even on sheet metal.
Welding on sheet metal meant, welding, using a hammer and dolly to flatten the metal, and welding some more. Heating a panel and hitting it with a wet rag to shrink a high spot.
One of the fun things was using lead as a filler. Heat a bit, apply acid, heat a little more, take a lead bar, melt some onto the panel, and use a wooden paddle to spread and shape it. It is a wonder any of us old guys survived. At least the lead made a more permanent filler.@@alfredocuomo1546
Nice job. Most times good enough is all that's needed.
Ive been a welser for over 55 years and i braze the same way as you do
I have a Cole vise that was split across the base of the anvil from abuse. I was able to "V" it inside and out and then preheated it with my propane weed burner. I set it up on fire brick and went at it with my brazing torch and Bronze flux rod. It brazed up beautifully and has held up well for several years now.
Hi Keith, I love your videos and have followed your channel for several years. I would love that you made a video about how you set your acetylen and oxygen before welding❤
a skill i need to learn!
That looks like a good job done . Thanks for all of your videos
Looks much like Kintsugi (golden repair).I've always thought a brazed repair looks attractive on a well used machine.
Especially if it’s a well done repair.
Hi Keith. Great video, been awhile since I’ve done any brazing. Great reminder. On another note, you gave a teaser a couple of weeks ago about building some wedge style footing/leveling blocks for the big Monarch Lathe. I’ve recently acquired a 100 year old K&T Model B horizontal mill. For several reasons I can’t use a traditional screw type leveler. When can we expect to see this video? Thanks.
Great job Brother Keith !!!
Awesome as Always What Happened to your HotShot Pre heat / cool down oven Wouldn't that fit?
It worked better after initial heating when you turned the flame down a bit. I'm surprised you never had additional flux to hand, I'm sure that would have been a boon too.
Thank you Keith!
Good to see some extra brazing added to the side act as a splint. The worry with cast iron seems to be "why did it break in the first place?" The original casting seems a bit thin given the load that could be applied to it.
Thank you for sharing. Very nice repair.👍
If you upgrade the kitchen tabletop toaster oven - glass door etc. Good to use for rods and metal. Dial and use a internal thermometer just until you trust the dial. They work great. Simple and large.
I have brazed many water well pumps.
I've had fantastic success doing old school oxy-acetylene flame welding cast iron with pure cast iron rods and powdered flux, but it requires the entire part is kept cherry red the whole time using a contained fire of some sort on the whole part. Then very slowly cooled like you did. However, I would love if there was a braze that color matched really well, then I might switch to that method to avoid having to make a contained fire each time.
My only suggestion is to put the parts to be brazed on a surface that is not a heat sink. Fire bricks or refractory tiles laid on the table would keep the heat in the parts rather than being drawn away by the steel surface.
Nice job! I liked the idea of using shims to keep the machined surfaces coplanar. I'm just wondering if you could get a few thin insulating shims to serve as heat-loss barriers. Then you could use ordinary metallic shims to set the total shim thickness. I don't even know if insulating ceramics are available at a reasonable cost or whether or not they would be durable enough for shop use.
I would have suggested an inexpensive fire-brick under it. Probably could have saved some gas, but it obviously worked out well enough even with the steel table.
@@TheFreshmanWIT , I thought of firebrick but I'm not a welder and don't know how porous it is. Here, however, the casting has two machined coplanar surfaces about 2cm apart in height. So, is there some sort of "foamy" ceramic that might be available in a thin sheet? The stuff they make spacecraft heat tiles out of would be perfect, but most likely horrifically expensive.
@@stuartschaffner9744 You could probably use a ceramic tile as well, but a firebrick is usually pretty darn flat and he could have put the same shims on it. It wouldn't have prevented THOSE from getting hot, but at least the giant steel tabable.
It's good to remember that not every repair is difficult or complicated.
It's also good to remember that skilled practitioners can make some difficult or complicated repairs look easy.
The only braze joint I've ever had fail was a prototype recumbant bicycle frame I built about 1982. The joint that broken was unreinforced and high stress, and I was using a weird pellet gas system at the time, so gas/heat was not optimal. At that point I realized I needed a real torch, and bought an oxy/acety kit the same week that I've been using ever since. I've actually had welded butt joints fail that worked just fine when brazed.
Good job
Good work
Nice Job.Well done!
Thanks for another great video.
Well done sir!
I'll say it again, our family farm has equipment that my grandfather and father brazed 60 years or more ago and it's still working just fine. A good braze is as strong or stronger than the original metal.
I'm curious how much brazing steel is from brazing cast iron in terms of difficulty. I've done both, but under different circumstances. During my college welding course we brazed steel, and after many hours of practice, most of us were able to make it look like a tig weld. When I've repaired cast iron, I didn't have an opportunity to practice for hours adjusting my torch settings before making the repair. With cast iron it seems like it wants to run everywhere and puddle up. The steel brazing we did in college wasn't just a superficial pretty bead layed down. It was two steel coupons brazed together, cut into strips, and the had a bend test done on them. So, I'm asking if there is anyone with experience in both that can tell me the difference in difficulty there is between the two.
Very nice job! I have no experience with this but noticed the two parts were not clamped to the table. May I ask why?
Putting numbers to what Keith said; A structural welding rod like 7018 has a tensile strength of 70,000 psi. Harris lists their RBCuZn-C which is a bronze brazing rod as up to 65,000 psi.
Impressive
Well unless he is going to be hammering on the drill press table I think the 10k psi will be more than sufficient for normal drill press usage. when it comes to parts like that I agree that oxyacetylene welding is better than TIG welding for the more uniform heating of the cast and the slow cool down is critical or you will create stress cracks and further damage the part. Nice job & good video.
Good morning
Nice job!👍👍
Would you not be better doing that on a couple of firebricks?
oooh! jig building thoughts dancing like sugar plumbs in me head ... just for alignment LOL
I was thinking the same thing. Then he pulled out the scrap pieces to shim it and all my allusions of a jig faded.
At least, he should have clamped the pieces down to the table!
Me, too. Surprised that a jig or clamps weren't used to keep the 2 machined surfaces in the same plane - especially since he mentioned it being an issue with the earlier attempt.
No oven in the shop, oh my 😅, I do though question you're no clamping the pieces to the table to preclude movement.
You do have an oven to preheat. Your heat treat oven which is fully programmable for temperature and time. And it appears to me the part is small enough to fit inside, and it would most certainly do a better job than the torch, because you said yourself that you want to heat it evenly.
Wouldn't he have to reheat anyway after removal from the oven? By the time he got it out of the oven and setup to braze, it would cool a bit...unevenly. The torch heating was a couple of minutes. The oven would take a while.
I'd say it comes down to what is the most practical process for the job that you are doing. I have a bad habit of turning five minute projects in to a career. Keith shows me how to find a balance.
@@oleran4569 When doing jobs like that, you setup everything ahead of time. What,15 to 20 seconds from the oven to the table, plus he could heat it about 20 to 40 degrees hotter to allow for transfer time. By the time he adjusted the torch from heating to brazing, it's a wash.
The irritation is that he said he didn't have an oven.
The broken parts are easier to set up in position when cold. The torch is a very fast and portable heating source that preheats the part much faster than an oven. No need to use an oven on a part this small.
Beauty!!!
Maybe I ask a silly question but… is there a significance of using a stainless steel wire brush rather than a ferrous steel wire brush for cleaning things as you go along.
Does that amount of heat going into a part distort the holes in any way?
I would think only if there was a crack to the hole.
can't quite say, but it looked like flux was bubbling out from the edge of the metal, almost like it wasn't hot enough when it was originally brazed. might have just been a reflection.
these rough castings are much cheaper chemistry. i prefer brazing like this most of the time but i have use nickle rods but the castiron needs to be really high quality.
There’s nothing wrong with our brazing! Forget the Monday morning quarterbacks.😅
Yo Keith, You have to be the king of brazing cast iron but I take issue with saying welding makes the repair weaker. We have been doing virtually undetectable repairs in cat iron sine 1980 using OXY-FUEL WELDING. We have done many repairs on antique furniture (Even pre-civil war) that after shot blasting and needle scaling look like it never happened. -And for stringth and mahinability, how 'bout the frame of a 100 ton punh press? (Even had Harris custom build water cooled torches for us)
I will say between you and Abom I hae started using TIG Si, Phospher, and Aluminmum Bronze for gear tooh repairs (depending on how dirty they are) I still say gas welding with cast iron rod ,,,,,,whih ampunts to selective re-casting ---- is the only way to truly repair cast iron. ------ Hey, I do 1000% agree Ni-Rod, and stainless is nothing more then camoflage and only mak a bad situation worse, but I'll tik to gas weld with real gray at iron rod for critial appliations.
And for the record- for the this appliation your way was 100% in my book.
Curious, this Harris custom water cooled torch. Can you explain more?
❤
let the tool do the work, dialing in the settings is the other half of the battle. cast iron smaw welding require peening with a hammer
My 2 cents worth. To remove the flux soak it in hot water for a while. It just dissolves.
bad engineering designed to fail, maybe add more bracing to the inside.
I would have thought you measure the c-c before snapping it. That has to be exactly right when it goes back on the machine.
Not that important if you think about it…it’s only a table….no precision is needed
Totally cheeky question, Keith: I notice the number "1582" on your worktable.
Does this number have any particular significance? For instance, your year of birth or something equally important?😈😈😈
Sorry.
It can be F1582 steel if it came from Spain or was meant to be exported to Spain, it's the UNE (Spanish normative) designation for 20CrNiMo4 steel.
You should pick up a couple of porcelain tiles for $4-5 at the store and put them under your work to prevent excessive heat leaching. Most are good for 2000f.
Not an expert compared to you certainly, but seems like it would make a lot of sense to insure that giant piece on the right is really hot before starting brazing as its got a larger surface area and mass and will suck the heat out of the smaller part and dissipate it much more rapidly when done, leading to internal stress/fracturing? Might not really matter here, however seems like relatively simple tweaks which should lead to slightly better results for 4-5 minutes time.
I wonder why the distance between the two holes was of no importance...
@wyrdlg I think it come off a drill press and only holds the table. I would think parallelism between the two holes would be more important
@@ianlulhamI agree. Even if the center to center distance was off a couple hundred thou(I doubt it is), it shouldn’t be an issue.
Another great job. I learned a lot. It sounds like you have come down with the same head cold I have.
Please or offend, but the truth is better to be shared than ignored, right, Keith?
Some viewers who watch this type of video are looking for more than entertainment. They want help, advice, and even a lesson on how to best deal with a situation they themselves are experiencing.
What I am about to say is not meant to hurt or offend anyone, especially Keith. But from time to time, we see things that need to be rectified.
We, as in, time served professionals, on occasion see things we know through experience, are wrong, and todays video is one such occasion. We owe it to ourselves to put things right.
I've been a qualified fabricator welder and engineer for more than 40 years. Through hard work and late nights, even weekends, I now have 3 apprenticeships under my belt.
I cut my teeth on oxygen acetylene gas and stick welding in the 1970s. The best, the only real successful way to fuse broken cast iron parts together is brazing, using gas, not a Tig welder.
Now, Keith, I know you are a good knowledgeable engineer and may well have brazed hundreds of cast iron parts over the years, but something I have noticed, we'll, there are two things, really.
First is your technique. With practice, and you must have had plenty of it over the years, comes finess. Practice means perfect as the saying goes.
Over the past year, almost every brasing job you have done, Keith has been somewhat sloppy. I'm sorry to say that, but it's true.
You've gone from adding way too much filler rod, so much that it flowed over the project piece, in effect, wasting filler rod and gas. To then go the complete opposite, by not using enough filler rod.
Over the years, you would have experienced that flux fills up voids unless you have your object and the nozel tip at the right angles.
As you quite rightly pointed out, flux turns to a glass like substance. There is no way to stop that from happening.
Flux, for those viewers who do not know, is a substance, usually an oxide, which is used in many things such as glass making, for example. To lower the high melting point of the main glass, which forms constituents like silica and alumina. In layman's terms, it's a form of purification.
Fluxes are substances that are also used in glazes and ceramics as in pottery for the same purpose. That's why brazing flux turns to glass. Now we understand what flux is and what it does.
Flux glass can give the illusion of a good, strong weld, a fools weld. That is why you are meant to tap the brazed joint or filler. In fact, you should tap ALL welding joints with a welders chipping hammer. The second most important tool in a welders bag.
These specialist hammers are used to remove flux and welding slag for two reasons. The first is to check that you have made a good weld. The second is to allow further welding to continue along the welding line or allow further welds to be placed directly on top for the same reason, as in mig or stick welding, which is common place.
Not to be confused with a wire brush, is that any novice welder knows, wire brushes with wooden or plastic handles are no substitute for a welders chipping hammer! They can not remove flux glass or slag like a chipping hammer can.
The last observation I want to address is that of the finished product.
As can be seen with the latest brazing project, your finishing is not of good quality or high standard.
If I were a paying customer, I would teturn the drill press platform bracket and demand that a better job be done. In effect, starting over.
Your attention to surface grinding is of a low standard. I appreciate that most of the repaired portion will be out of sight, but that does not excuse poor workmanship.
You should have paid more attention to grinding and sanding away much more of the braze overflow than you did. What is showing gives the illusion that the weld is weak and unfinished.
The inside of the bracket does not matter, but the part everyone can see, as seen in your closing shot with the part in your hand. That area should be roughly the same level or flatness as the bracket itself.
When you showed us the bracket at the beginning of this video, we could see the previous weld was nice and smooth on the outside, as it should be. The inside was rough, uneven with blobs, which is acceptable.
We could also see and hear you say that the break had come away probably because the bracket was not evenly heated up prior to welding.
In fact, there are any number of reasons for that break happening.
In conclusion:
Providing you grind all edges to be welded at the correct or as near as correct angle, possible in the shape of a V.
Heat up all parts evenly and the parts to be welded to a cherry red colour.
Place cast iron parts at the right angle, which, if done right, will allow a good weld pool to flow.
Have your nozel at the right angle, which, when correct, will allow the purfect flow of molten rod to adhere to both sides of the cast iron.
There should be no more than 1 to 2 mm of excess braze to be ground, then filed away to a smooth finish.
It sounds difficult but far from it when you know how. My advice for anyone wanting to learn how to achieve the best braze weld possible.
First, watch several UA-cam videos to get a different perspective from different welders techniques. Then, practice welding two pieces of steel together. Grind away the excess filler and finally file smooth eith a file chisel.or sanding disk.
Then, put the piece in a vice and bend it 45° then another 5°and another. See how tough your weld is before it breaks.
Look at the break and see if there are any voids or flux glass. If there are any you will be ble to tell the difference between them.
Then start again. Grind both parts clean and weld. Bend, snap, and clean. Rince and repeat again and again until you are happy with your welds.
It may take you a day, a weekend, a week but don't despair. Like with most things in life, you will get there with dedication and hard work.
I don't know why he keeps embarrassing himself over and over he keeps saying i am happy with that but that doesn't mean it's right way.
ther eis a powder weild also for stel and cast to build the surface up and then give it a new surface .. with out going in to deep in the wall...
You may be referring to a Stoody torch for spray welding. I used it to repair a cracked manifold with great results.