Impossible Gears | Design for Mass Production 3D Printing
Вставка
- Опубліковано 27 лис 2024
- In our pursuit of producing a $10 spool of filament, we realized we needed to make some improvements to our filament extrusion line. So we decided to design a 3D printed gear in order to improve the machines belt system.
In this episode of Design for Mass Production 3D Printing, we uncover the high costs of traditionally machined pulleys, crafted from blocks of steel, and how employing 3D printing technology, allows for more cost-efficient and robust gear production.
Learn how to design gears effectively, understanding the benefits of 3D printed gears over their metal counterparts. We demonstrate the versatility and reliability of 3D printed hardware, showcasing its capability to match, and even exceed, the structural integrity of legacy materials.
If you would like to learn more about how to change your approach towards manufacturing products with Mass Production 3D Printing, make sure to SUBSCRIBE to Slant 3D!
🔗 IMPORTANT LINKS 🔗
Get a Quote for Your Production Project: www.slant3d.com/
Slant 3D Etsy Plugin: www.slant3d.co...
Get Our STL's: www.angled.xyz/
Get Affordable High-Quality Filament: www.tangledfil...
Try Shapr3D (Use Code: Slant3d): www.shapr3d.co...
Our Favorite Products: www.amazon.com...
About Slant 3D
🏭 High-Volume 3D Printing: Scalability Meets Flexibility
Slant 3D's Large-Scale 3D Print Farms utilize 1000's of FDM 3D printers working 24/7 to offer limitless scalability and unparalleled flexibility. Whether it's 100 or 100,000 parts, our system can handle it reliably, while still allowing for real-time design updates, ensuring products evolve with the times. This adaptability is key in today's fast-paced world.
🌿 Sustainable Manufacturing: Eco-Friendly Efficiency
Embrace a system that drastically reduces carbon emissions by eliminating carbon-intensive steps in the supply chain, such as global shipping and warehousing. Our approach minimizes this footprint, offering a more sustainable manufacturing option.
⚙️ Digital Warehouses: Parts On-Demand
Think of print farms as a "Digital Warehouse", meaning we can store your parts digitally on a server rather than physically on a shelf. parts are available on-demand, reducing the need for extensive physical inventory.
Produced by Slant Media
As an Amazon Associate, I earn commission from qualifying purchases.
Produced by Slant Media
Interesting fact: most of the cheaper timing pulleys you buy are actually made of extrusions.
The pulley tooth form is extruded and sold by the foot, then the pulley supplier saws off a length based on the pulley's final width.
Then they turn the faces true, bore the bore to spec, and press (sometimes glue) stamped flanges on the sides.
If they machined the whole profile, then timing belt pulleys would cost several hundreds of dollars instead of single hundreds of dollars.
But even so. It can't compare to the cost of 3d printed for low-speed low-torque applications.
Do you have failure data for max speeds and torques on the ones you've printed?
Very True. Great Summary of the Alternative methods.
It always blows my mind that you can extrude metal. Even aluminum, but especially steel
@@melody3741 Everything's a fluid if you push hard enough
Sometimes the "flanges" or belt keepers are a snap ring after they turn a cut into teeth on the edges.
@@melody3741 I highly recommend looking into the massive presses used in manufacturing. Machine Thinking has a video called "America's Iron Giants" on presses that output thousands to tens of thousands of tons.
By the way, the Solidworks CAD models McMaster-Carr provides are fully parametric native parts. You can totally download a 50T sprocket and change a few numbers in the CAD to make a 213T sprocket for whatever you need.
Fantastic info.
Fusion 360 also lets you import parts from there too, they also have it build in, I haven’t tried to alter the parts though.
This reminds me of a project where I needed a custom drive wheel in an electric wheelchair. In my first iteration I used the hub from an existing aluminium wheel and bolted it to a printed outer as I was worried the key way would shear in an all plastic printed part. In the final iteration I printed the complete wheel and hub with keyway as one unit. I then tested that by locking the wheel and stalling the motor at full power - nothing broke. The key way and shaft look very similar in size to your example and it was a 2.5HP motor.
I would be very hesitant to print a pulley out of plastic that size for a couple of reasons. One is the key at the bore will have very high stress risers at the corner, and you're at risk of blowing out that bore with a fairly small amount of torque. You may be able to get around this with having an aluminum sleeve made that interfaces with a much larger contact patch with the plastic, but interfaces with the output shaft and key of the motor. The second one is a bit more challenging to overcome. I don't know exactly what style of belt you're running, but it looks like a Gates Powergrip GT2 (maybe 8mm or 14mm). The problem with 3D printing those is that the tooth profile is (last I knew) still patented and proprietary, so you need a license by gates to produce them (if profiting). This also means that the actual profile generally isn't available publicly. The profile you get off of most sources (including McMaster-Carr) aren't the actual profile of GT2 pulleys you'd find on a licensed pulley. It may mesh, but you're losing efficiency (which may or may not be fine for the application). Also, most Gates timing belts aren't "just rubber". They're often fiberglass or some other fiber strands and polyurethane teeth that make them much stronger than plastic.
That might explain why the teeth don't seem to grip consistently at 4:43
@@Nigel_Tufnel_11 I think it would be difficult to say why that’s happening without seeing it in person. Usually the publicly available profiles mesh fine, but the difference might be increased friction due to material changes causing the belt to climb out, but there also may be other reasons like non-proper belt tension. Hard to tell.
@joecrow13yeah, certainly doesn't look like a perfect fix to me...
still, 3d printed pullies are cheaper and easier to get than 1 steel one for probably decades of logevity. also, no reason you could not get a simple keyed hub with a bolt circle and print the timing belt profile and bolt it on, that part would be considerably cheaper and it changes the force dynamics on the plastic components. now it's even less plastic and it's easier to maintain the production line as they wear.
source: i'm a cnc machinist. a cnc with live tooling would knock that out in 15 mins with conversational programming, and broaching the key would take 5 mins. so what, $50 in shop time + cost of steel and you have a part that will last forever and adapt to any tooth count over the major dia + w/e meat is needed to support the teeth and bolt circle on the printed part. considerably less than the cost of a full steel timing pully.
manufacture of these is actually very simple. I've seen it done in person and even on low sample volumes it should not cost more than $40 MSRP.
I think it has an extruded center section with stamped and pressed on flanges. But point taken. I can see in your running belt that your tooth pattern does not line up. The belt periodically rides up on top of the teeth. Perhaps you failed to measure and enlarge the part to account for shrinkage. I would suspect something in the range of 1 or 2% would be required.
That is a very wobbly "timing" gear. Really, this is something that could in total cost be solved cheaper by just digging through McMaster.
I discovered this channel only a few days ago, and in that time I have learned so much from Discount Ryan Reynolds. Thank you, Discount Ryan Reynolds.
I mean i made new gates based pulley for a mini lathe but i dunno if this would even be near the precision.
I actually made it completely configurable in cad for profiles and also tooth count. With two parameters.
I did see with gates belts you do get the issue with the stuff being quite abrasive when plastic on plastic (sometimes even fiberglass).
The metal is never wasted when taken away from the part.
Im sorry, but at 4:43 it clearly does not run smoothly. You can see that the belt is clearly moving and not fully engaging. This will have an impact on the rotational speed of the output shaft, so it will not be constant.
It might be ok for you, I dont know, but this is clearly not a 1:1 replacement.
That looks to be the metal part.
that would look to be a tensioning issue, which would probably be intentional to reduce wear and wouldn't have a very significant effect on efficiancy
I'm actually curious about the long term durability of the part, but I imagine that won't be known until it's been in use for a while.
Id wager the keyway is the weakest link, but id imagine having to replace it 4 times a year would still be cheaper than needing to replace the metal gear once every 50 years.
That depends on how much downtime costs you.
@@thesoloveichiks159 polycarbonate is only a pain if your printer isn’t set up for printing it. Carbon fibre filled filaments aren’t recommended for gears or pulleys due to the extra roughness of the carbon fibres, they are very abrasive. You are better using a filament designed for low friction, like PC-PTFE, some nylons or something like the IGUS filaments with built in lubricant.
Why do you use a massive timing belt for something that isnt under massive load?
Ratio.
I like the concepts you put forward. My only issue is the strength of the keyway. The belt teeth have many points of contact to transfer the torque but the keyway only has 1.
How have you strengthened that section of the part?
Saying the printed parts "perform just as well" (at 4:41) while showing the belt skipping teeth ... whoops! Maybe not.
second =)). the pulley looks wobbly though. maybe use some subtractive manufacturing as a final step to get the teeth surface consistent and make sure the shaft is centered. if it doesn't affect the filament consistency it is fine as is
Just designed and printed replacement gears to fix my paper shredder and pencil sharpener last week.
You hit a bunch of great topics here on the head. But My question is, What kind of metrology are you doing, to insure that your achieving something within the tolerances you want? There's a lot of parts where this might not be a big concern. But personally I would find a timing belt or gear to absolutely critical when it comes to reproducible and accurate dimensions.
Actually, while it’s called a “timing” pulley, in the vast majority of applications we don’t care about the tiny fluctuations in tooth-to-tooth times, we’re just looking for a transfer of power and the overall ratio relative to the drive pulley. That’s pretty easy to achieve, and there’s enough play in the belt system to make for pretty loose tolerances (at least compared to precision machining).
The belt itself has a lot of flexibility, the teeth on it are somewhat less so but still are very tolerant of slight variations in the geometry of the mating teeth on the pulley. The diameter needs to match the number of teeth and the tooth pitch but again, it doesn’t need high precision. As long as you have the right number of teeth that will mesh reasonably well with the belt, you’ll have your desired ratio relative to the driving pulley.
@@roscoepatternworks3471 There are for sure different applications that have dramatically different tolerances. I don’t know the specs for a car’s timing belt and associated pulleys, but I can imagine them being pretty tight. I think it comes down to whether you’re “timing” something or just looking for energy transfer. (Calling them timings belts and pulleys is a bit of a misleading term, a lot of times we just use them in place of a regular pulley because we want more torque without slipping - Or simply because we have parts in hand from our 3D printer fiddling :-) I admit that my thinking tends towards looser specs, because I’ve only used them in hobby projects or working with kids making a robot. For those kinds of things, 3D printing seems to be fine.
@@roscoepatternworks3471 Well, that’s an example of where we *do* care about tiny fractions of a rotation. It’s a matter of whether you’re primarily interested in power transmission using a belt but with low to zero chance of slip or if precise positioning is important. (Not either/or, sometimes you need both.) if you need precision, then yes, you probably need metal pulleys. If you’re just using it for power transmission (as in the filament puller in the video), then printed parts are just fine.
I modeled and 3d printed a variable pulley for my lathe. It fits better than the original, but I need to stress test it to see if it holds up under load. It is PLA + and it may have problems if it overheats.
3D printing costing way less than machining also makes it a lot more accessible to someone like me with a very tight budget, and largely only requires learning CAD, as opposed to how to use a bunch of different machinery (as well as acquiring that machinery, and finding a place for it, in the first place)
a very niche example (no mechanical strength requirement), therefore the benefits are so blatantly obvious. Still, a good one and a way to go.
Since the critical part is only the keyway, it might male senso to machine an insert from i.e. aluminium hex stock that fits all sizes and just print the less stressed outer parts. Then you'd be able to extend the usability.
This is so awesome. I always learn a ton watching your videos. Thank you!
I'd like to know how much does the new big gear weigh?
Is it possible to give an estimate of how much say 1kg of printing would cost in your printfarm, but then "in the limit" if I were to keep your printfarm busy for something you feel comfortable with.
Just out of curiosity: how many wall lines have you there?
So commibg from a reliability background, i wonder if since plastics arent the best medium for vibration to transfer through, if 3d printed sheaves would help reduce vibrations from belt lash or at least not transfer them from driver to driven component .
This video is very good, i like the visual and informative side of this video but i must add this one detail. Modeling gears is not really that hard anymore. For example. In Fusion 360 you have a feature (or plugin i have it in there for so long that i don´t even remember if its part of original program :D) called Gf Gear generator,FM Gears, etc.... Which as the names suggests lets you make mostly any gear you can think of. Even this one and one could probably make this gear in less than 30 minutes (maybe + 5 minutes for adding the sides for belt to not slip from the gear) So the time you designing this can be very easily reduced.
Also second thing i wanted to say, its possible to use hollow PLA model of that plastic gear you made and cast it with very good result. Many are using 3d printers for casting and many are even casting gears like yours(mostly from aluminium) though the process is still longer than just 3d printing which in this case is more than enough for that belt :D
All else constant, metal will last longer. You could 3D print one out of plastic, then proceed to cast the metal using one of a variety of methods (e.g. lost PLA, sand casting, graphene mold). Make one out of say, bronze. Obviously, ensure that your casting job is of sufficient quality by removing slag, heating molds if necessary, compensating for the center dip due to differential cooling, minimizing occlusions due to air pockets and rapid cooling, hardening, etc.
I have learned a lot from your videos. Could you do one on how to best design a gear for 3d printing, particularly with regard to maximizing the tooth strength? Thanks for taking the time to make these vids.
There's a precision gears addon for blender from Maker Tales. I believe it's pay what you can. It even make gear simulations reasonably easy to achieve.
Additionally, to make the plastic gear even stronger you could include a brass shim in the center.
Blender is not the right tool to be using to make mechanical parts. You are much better using a proper CAD software and most of the big ones have gear generating tools built in or available as plugins.
@conorstewart2214 I don't care Conor. I'm choosing to learn blender because it's basically free. Minus the pay what you can add on. It's still basically free compared to software that comes monthly sub or one time payments. Realistically how much software can you choose to learn and be committed to pay for. If I wasn't being paid to use Adobe software, I sure wouldnt be paying $1200 a year for all the software that still can't generate a gear. As, I was just gonna learn the math and draw the gear myself in Illustrator. Still, not the right software. How much software do you need for one simple gear.
@@FunDumb I use Blender as well but there is also FreeCAD which has a GEAR add-on which includes GT2, GT3, GT5 and HTD8 profiles.
Tangled Filament. LOL. Love the reverse psychology marketing. :) I was hoping you were going to explain the change in diameter from the OEM pulley to the new one. Care to share with the class?
If we had automated resin 3D printers that cleaned and post cured their own parts, and UV curing resin became a low cost commodity material, imagine how awesome and inexpensive pulleys would be. Not needing to use subtractive machining processes would greatly reduce the commercial cost. Even now, people at home can download pulleys and print them on an FDM 3D printer, and print them on an MSLA printer if they need to be stronger. Want to change the gearing on your Kevlar belt powered motorcycle? Download the pulley that fits your bike and resin print it. For ultralight pulleys, finite element analysis can help design an optimal pulley with material only where it's needed. Very soon, the only metal pulleys will be in very high temperature applications.
For those who prefer writing code to drawing on their computer, OpenSCAD is great for timing pulleys. Change the number of teeth in the code (n=32) and it generates a new pulley size.
I would like to know what is the name of the music playing in the background.
Bro what would happen with the massage rollers?? Could you sell them in cults or something pleaaase bro?
I feel you could've explained this in 2 minutes tops.
If you needed more strength for rotation and for the keeper you could lazer cut the keepers and the keyway out of a metal.
If always found the belt keepers a weak spot in some applications. The biggest weak spot for my application has always been the shear pin luckily yours is using a key way. 1/2 the time may application has an alloy pully then the other half its a fiber reinforced plastic..
I think the sheer pins actually fail after some waer occurs between the output shaft and pully and that little bit of play will kill any roll pin more than the rotation torque.
Wear at the teath has alway been an issue on the fiber reinforced pully. I tend to think this happens from over tightening the belt and letting a belt run too worn.
Link to buy filament please..
1-3 hunderd dollars for a pulley like the one you are holding in your hand is a massive ripoff, a pulley like that which looks like HTD 8m 36 30 shouldnt cost you any more than 30usd , really big ones that were cast then machined like 8m 112 30 cost us around 130 usd (in europe).
The cost is related to getting a timing pulley with the exact ratio of teeth needed for a particular application. While some pulley's have a common number of teeth, its the lower volume specially ones that have much added cost. This a result of fewer parts produced for the same amount of engineering and tooling costs.
The only reason pulley's are priced the premium they are, is no one is producing them at a lower cost.
Pricing of similar kinds of parts is about to be disrupted!
Are you going to find an alternate way to sell the massage roller files? I was s $9 backer and saw the message last night that the campaign ended.
well, precision gears is available
The teeth on the metal gear will wear significantly less than the plastic one. You will have to change the plastic ones much more often
Incorrect.
Did you print this at your farm? It looks too big to print on your machines. Or am I misremembering the build volume of the slantbox?
I mean, they would have a couple large form factor printers as well, right?
@@Litl_Skitl from previous videos I had come to believe all slantbox printers were a standard size, with a build volume similar to an ender 3.
@@McRootbeer Doesn't have to be a slantbox. Maybe they have a handfull of vorons or a V400 somewhere.
what is the name of the music please ?
what about wear and heat?
Most of the wear and heat is within a rubber timing belt. It's a softer material doing more flexing. Many belts will need replacing, before a timing pulley is replace.
Would be much easier and way faster to layer pieces of delrin or UHMPE(CNC could do it in a snap) or laser cut(could be even acrylic plates), then use reinforcing bolts+nuts to hold them together. Also could add a couple of even spaced pockets on top and bottom plates to help with adding weights(may be even epoxy, hotglue!) for a better balance. Just some suggestions.
That's still many more man hours than to just print a PLA gear that does the job and nobody has to check on the machine while it's being made.
@@carlosjosejimenezbermudez9255 A 150W Co2 laser could cut several 3/4" acrylic sheets like butter in as little as half hour.
The cost is nothing much other than that of few sheets of acrylic.
With freely available CAD 2D gear generators, it hardly will take any time to create variations. Assembly with nuts and bolts may be 10 more mins. 3D print will take humongous time of several days?, and in no way comparable to strength of laminated acrylic or delrin. Injection molding is better, but cannot handle solid parts, and may need a 200 ton machine with several oz capacity, to prevent shrinking and sink marks. The approach I mentioned, is similar to the highend carbon fiber lamination, except cheaper and faster!.
Co2 lasers need zero supervision, when setup right. Always precise and repeatable. It is actually a 2.5D operation in this case.
@joecrow13 No wonder its used(as POM gears, press fit on large hobbed steel discs that feed filament), in lot of high gear ratio highend 3d printer extruders🤔, only alternative being a cast/machined gears, that are expensive to manufacture.
@joecrow13 That's an interesting application! The self lubrication definitely does help. I do find delrin cuts crisply on a CNC vs Laser, but not that bad as the HDPE. For the specific pulley application, it might even be beneficial, to have a slightly rounded tooth, to reduce belt wear.
In no way is machining them going to be easier or faster. If you are going to machine or laser cut them then you need a CAD model or drawing anyway and if you cut them as sheets and stick them together like you suggest then that requires post processing. It is much easier and faster in terms of time spent on it by a person to just click print.
Why in an application like this would you need to add weights?
Did I just catch that you have an engineer running your printers?
Seems like overkill, a technical specialist could do the job workout becoming disgruntled that they aren't using all of their expensive qualifications...
When he means that, he means running the print farm, not just one or two machines.
@@SirSpence99 Point taken, but still probably doesn't need a degree...
Design yes, operation and troubleshooting unlikely
@@thecrapadventuresofchesimo420 When you are watching a board that covers hundreds of machines, a decent chunk of the time is identifying ways to optimize the process.
Your comment makes the assumption that their engineering degree is, both the beginning, and the end, of fields they'd be eager to work in, interests shift. So long as they are paid fair and enjoy the work they do, I kinda doubt there is disgruntlement. They might demand a higher wage due to higher qualifications, but that means there's more they can contribute, 3D printing often is engineering.. what breaks on their machines most? design it better, etc etc.
What I got from this is yall pay your engineers $150/hr
Пластмассовый мир победииииил!
Макет оказался сильнееееей!
$150 to $200 to for someone to model that pulley? Here I would ask $5 or $10 if being greedy. An easy peasy job
Need to get out of Argentina.
The $150 isn't for modeling it, the price is for the block of metal and the costs of labor.
I guess they don't pay engineers in Argentina? $100 per hour. Takes maybe an hour to get a first draft and one more to make refinements. That's $200. Engineers are expensive. I have no idea how they can afford me, but I guess they make even more of what I do
@@timonix2 It should take an "engineer" less than 15 minutes to model that pulley, taking into account the time to google "how to 3d model a pulley" and looking a 5 minute youtube video
@@nirodper Ah but you forget. You need a 30 minute meeting between the stakeholder and team lead and another 30 minute meeting narrowing down the specification. Then you actually make the part and realize the specification is wrong.
yeah the teeth might not fail faster then the belt however you've created a large reaction arm by making that pulley larger and thus your keyways will sheer out of that bore
Math says no
Fair enough i was just replying to the remark of the teeth being strong enough even though thats not the weak point. But iff the pulley works it works fully agree with not paying 100+ euro's on those big timing pulleys
The problem with injection molding is NOT shrinkage, it can be easily compensated.
If you can 3D print it, you can injection mold it better. As long as it is not complex enough geometry, in this case pulley, is not.
Incorrect
That is just totally untrue. You can print things much more complex than you would ever manage to injection mold.
Getting all the teeth right if you injection molded this would require quite a few mold parts and hence would cost a lot and be difficult to do in the first place. You would need multiple mold pieces for the teeth around the pulley and you would need to make sure every tooth profile is right, even where the molds join which would probably require a decent amount of post processing.
@@conorstewart2214or you would just modify the design for molding like you would for 3D printing. You can make complex geometries with an injection mold no problem if the design is tailored for the manufacturing process. Clearly the investment will be higher, but the end product will be of higher quality. Someday we will live in a world where people realize 3D printing is great but isn't going to displace every single manufacturing technology. In fact only an idiot would get this part molded, they are extruded and made extremely cheap with process.
@@slant3dwhy not elaborate instead of a crappy one word response to a reasonable statement? I have never seen a 3D printed part that is better than the same part injection molded. They're also significantly stronger and more consistent. Why 3D print for mass production?
First!