Hello everyone, I was wondering if there is a website that I can find models of FRC parts that I can print on a 3d printer. Also what is the best type of Filament you can use for printing gear boxes and gears? Thank you for your time!
Thingiverse.com is great for models. Andymark has printable products aswell. You can also simply save anything as an STL and print it as you please
Printing gearboxes… that line scares me abit. This really isn’t what 3D printing is for, even if you are using nylon or carbon fiber. Plastic bends and forms out of shape much too easily to be used as plates. Printing gears is a huge maybe, but honestly buy them on McMaster-Carr, they are probably stronger and cheaper than printing in nylon.
I’ve found the most useful things of 3D printing to be spacers, mounts, prototyping complex mechanisms quickly, and mostly anything that isn’t going to be in a high torque or impact situation.
By the way, what printer do you have? That will slightly dictate what you can and can’t do with it.
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Let’s pump the brakes a little bit! Plastics can be the perfect material for us in robotics, as long as you select and utilize it correctly. For example, 0.25" Delrin sheet makes for some outstanding gearboxes. We have a drive base built in 2008 that’s still driving nicely, and it uses delrin sideplates. Gearbox housings can absolutely be made printable. Check out Griffingear’s offseason bot (it showed at Chezy Champs) for a practical example of printed transmission housings.
When dealing with FDM/FFF, layer orientation becomes a critical factor for printed parts. If you have access to SLA/SLS, toss those concerns out the window and start getting crazy with your designs.
Now, back to OP:
Any of the CAD files on Vexpro, Andymark, McMaster, etc can all be printed. You’ll just need to convert them over to .stl files (ewwww, stereolithic formats are lame!).
Gears are difficult. If you can do ABS, or maybe some of the IGUS bearing plastics, you’ll have a slightly better go of FDM gears. The main problem shows up in surface finish, as well as interlayer adhesion problems. When you buy a metal gear, that gear is isotropic (the material properties are uniform all the way through). When you print a gear on FFF/FDM, the gear has all sorts of imperfections and strength issues that can cause added friction, non-smooth rolling, and interlayer failures.
That being said, TRY it! The cost of failure with additive manufacturing is FAR below the cost of failure for traditional means.
It’s so great to see more people looking at 3D printing as a viable means of manufacturing now! For gears, I highly recommend Nylon 910 - it’s relatively easy to print and (from our tests) fairly wear resistant. For the actual plates, we like to use PETG as it’s relatively stiff and even easier to print than Nylon 910. We’ve printed many mechanically demanding parts so far, and they all seem to be holding up super well.
Edit: I don’t particularly recommend printing gears right from McMaster files; try to find low DP gears so the teeth are larger and stronger.
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Thanks for all the replies, Our school just got 3 I3P 3D Printers. I printed off parts for the FTC team and they so far are holding up. I was wondering if I should use a certain plastic for parts on the FRC robot once build season starts. Is Nylon 910 and PETG the best options for printing parts? Also when I save the models as STL files will they the parts be the exact same dimensions as the part you would buy off the shelf? Or will it be slightly off? I printed a Mini Tough Box gear housing and it seems to be slightly larger then the original off the shelf housing.
4818’s 3D printed swerve drive would like to have a word with you.
(it should be noted that to my understanding, 4818 has access to an extremely high quality 3D printer through a sponsor, so results may vary)
Ok, I’m really interested. What machine and what materials did they use for those gears?
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I’m not entirely sure which printer they used, I’d assume some sort of industrial printer capable of printing in rubber for the wheels. They were giving out incomplete prints of their gears at Iowa though, and it seemed that they may have just used plain old ABS with generous infill and a pretty thick shell.
Do you mean 3d printed whole bot…
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GrabCAD should also have files you can use, although I would more strongly recommend AndyMark.
7307 has been experimenting with 3d printed robot parts. One thing that we have found works pretty well is 3d printing bearing blocks.
https://i.imgur.com/o5eRZLs.jpg/2’
There is one that I printed as a demonstrator to new team members as well as to potential sponsors to show the kind of things that we do.
I am not very familiar with 4818. A quick look on TBA shows they had some struggles at their events this year (seeded 47th and 33rd at their two events, missed elims at event 1, and lost in QFs at event 2). I’m curious if they had any issues with their swerve? I’m actually not very worried about the 3d printed structural pieces of the module, but the steering bearing method their using seems shaky has a couple times in the video you can see a module visibly wobble, curious to know if that is due to a bad bearing choice or something to do with the printed parts they used.
Perhaps someone on 4818 will see this and can shed some light.
Overall I think 3D printing is a fantastic tool for FRC. It cuts down on the amount of machining time needed, and you can get the design to be more exactly what you need without having to consider how it will be manufactured (as much). That being said, while I think you can print gears for some applications (steering a 3D module should work, look at 125’s 3D printed bevel gears for their hopper feeder from 2017), I would be a bit skeptical about the high speed and load that drive gears would see, and how quickly 3d printed gears would wear. Not saying it’s impossible, but some extensive testing would need to be done on this before I felt comfortable running them on a competition robot.
Also running 3d printed versions of regular vex hex gears doesn’t seem that beneficial to me. A very small amount of weight savings, cost is probably negligible, and it actually takes me more personal time investment. Not sure the headache of figuring out if the printed gears can hold up is worth doing here.
For driving gears, agreed.
We printed a 64 tooth Vex gear out of ABS last season that performed wonderfully. We modified the hex to instead allow us to clamp the gear directly to an AM absolute encoder for our swerve module. This let us have 1:1 absolute pivot sensing with minimal hardware investment. It also meant we could remove a module without needing to disconnect any sensors.
There’s many uses for 3D printed components on FRC robots, not just as a replacement for normal COTS parts.
As the 1st pick in that “lost in QFs”, I can say that we scouted them as a decent team, and actually even had them slated as a potential 1st pick due to their ground gear pickup and swerve drive. I personally thought they pulled off the swerve itself really well, so I wouldn’t pin any issues on that.
I was explicitly saying using a 3d printed gear to directly replace a COTS part isn’t that beneficial. The example you gave isn’t doing that.
Trust me, there is definitely a time and place for 3d printed gears, but replacing a 20DP hex bore 7075 gear isn’t one of them. That’s all I was saying.
Having done 3d printed gears a few time, I have noticed that while they work, the tend to have a lot more friction compared to the equivalent cot gear. However, 3d printed belt pulleys seem to work extremely well.
The best thing to to is to get some different filament and give it a try. I’ve been happy using PLA for most things, unless they might get warm and then I’ll switch to ABS.
One observation that I’ve made, though, is that since I’ve started sticking to one type of filament on a printer… and not swapping between filament types… that my number of hot end jams has dropped to almost zero.
A few people who have tested different filaments have come up with some interesting reading material. Here’s a couple I’ve found interesting:
Jason
Check out ABSR for gear boxes and tough for parts that can be flexable and not break https://store.printm3d.com/
As someone who’s thoroughly invested (and addicted) to 3d printing, I really don’t think there are many applications for outside of non-structural components.
Don’t get me wrong, I’ve seen some incredible prints used on extremely successful robots, (2767 comes to mind…) but it takes a lot of thought and effort to make something like that work. I believe I’ve even seen gears printed for combat robotics too…(Maker’s muse)
That said, in the last few years, 3d printing has come a long way. I print plenty of parts for quadcopters and such, and I’ve found that carbon reinforced nylon is incredible for most applications where I need a durable part. Polycarb is also great for little parts that need to take a beating. The huge issue with printing specialty materials like these is that they’re incredibly difficult to print. Polycarb requires a serious printer, and CF Nylon is notorious for ruining nozzles.
We’re getting there, I’d how teams use 3d printing in 2018 (other than electronics brackets 
)
Does this count as an electronics bracket?
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