I have seen several teams that are using mecanum wheels on their intake roller. These wheels appear to be relatively small, and in some cases 3D printed. Any idea where I can find the files to be able to 3D print the wheels?
This is my favorite (https://grabcad.com/library/adjustable-mecanum-wheel-1)
There are many different versions on GrabCAD/ChiefDelphi. I would print a couple versions and test them.
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The Thrifty Bot has CAD for their intake wheels on the website
Weve printed these with great success just using PLA.
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You can use Find Robot Parts to sort through the known wheels out there: https://findrobotparts.com/wheels/
Thanks, I’ll give some of these a shot. Hopefully our printer can make a decent enough part.
I tried to print these wheels and each time the print errors in the exact same spot. Have you had any issues with the files?
what part of the print is it failing on?
Pictures would help. We went from the STEP files (to make a few small changes first), and they’ve been printing just fine.
After it does the raft and begins to lay down the first few layers. It fails on one of the wheel halves. Same spot every time. I printed another file as a test and it printed fine so it shouldn’t be the printer.
Echoing Jon pictures would be very helpful
Fails how?
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I don’t have any pictures, as I have discarded the prints. All I can tell you is that at a certain spot in the print the head stops moving and stays in place, and will not resume.
That sounds like an error in the g-code/slicer more than a problem with the CAD. Maybe try with a different slicer, or make a very minor edit to the CAD (ex. a small fillet on a hole) and reslice it?
It does this at that same point every print. It prints other parts fine so it’s not a leveling issue
I’d go back to the step files, export everything, slice it, and try again. If that doesn’t work, then there’s an issue in the process somewhere, because the step files are fine.
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That last print is a step file export that I did. We are using cura any other slicer that you can recommend?
Coming in late here, but the CAD on Thrifty’s site isn’t printable. TTB VIW’s are two markforged parts with machined rollers, some pan head machine screws, and possibly a threaded insert. The STEP file on the site is external surfaces only.
Oh good to know. Maybe we should look at printing other wheels unless there is a way that we could modify the CAD. Would you know how to do that
Reposting from another thread but here was my process:
If you want to reverse engineer them yourself then what I did was first download the STEP files off the Thrifty Store and import them into your CAD program of choice. To get the body I cut away the top half, cut away the roller(leaving the center nub that the roller rolls on), trimmed the center nub to a reasonable length, and adjusted the three holes on the center (a clearance hole for #6 bolt, a hole the correct tap size, and the 1/2" hex, each of which I oversized slightly because my printer likes to undersize holes by ~0.25mm). The roller I just made from scratch based on the dimensions from the original file, it’s a chambered hollow cylinder so nothing complicated. For the other side wheels my slicer has a mirror feature so I just used that. Print 2 body halves and 6 rollers and you’re off to the races.
After printing I cleaned up the roller holes with a drill to get a nice surface and tapped the to-be threaded hole in the hub. But other than that very minimal post-processing, didn’t need any support material which is always nice. And even with no pins they’re so far proving robust enough for prototyping, no parts broken out of the 17 we’ve printed so far.
I already went through the process and Ryan gave me permission to share them if you want a copy. I won’t promise they couldn’t be done better but my version is working great for my team.