In the tab on the bottom labeled “Left Wheel”.
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Thanks a lot
We’ve had incredible success with the split version of these wheels in our indexer. We have a couple on our intake too. One note-the screw holes don’t line up properly, so we had to glue all the wheels instead of screwing them together.
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A) Love it
B) I’m curious what you mean when you say they didn’t line up? The ones I’ve got seem to align without issue. The two countersinks end up opposite of each other with the bolt threading into the plastic. If you have any pictures of them not lining up or more details let me know so I can resolve any issues.
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That is going to be the smoothest indexer ever, but it made my hands hurt even more just thinking about filing down the ends of every one of both ends of those rollers. What does that LEMON indexer weigh?
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No filing at all; only the hex bores needed a bit of filing (there’s a 1/4" spacer between each mecanum) and the passive rollers were literally just long pieces of roller that we had in the back of our shop. It’s 10 lbs as of now (2 VPs with 775s and no pocketing on the aluminum drives that up more than we’d like, we didn’t have time or energy to properly drive off one motor so we just used two). We will likely update it at some point throughout the season.
I’m referring to how when you line up the little nubs with the divots, the two countersunk sides end up parallel with one another so that one bolt feeds through both countersunk parts and the other hole is unusable. We checked printing both sides from the CAD and two of the same side (since we hoped each wheel was two symmetrical pieces sandwiched) but the file was the same regardless. What we’d need is another half that just has the threading and countersunk holes reversed, then you print one of each to sandwich properly.
Idk how I missed that… I’ve updated the model got a test print running right now to verify it’s resolved. Should know in about an hour or so
Edit- yup, resolved.
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For anyone using Cura to slice, we had success using the Horizontal Expansion setting to reduce the size of the polygons, increasing the clearance. A value of -0.3 gives a fair amount of play and makes it free spinning off the printer. I think that’s about the most I would open it up. It may be a little too loose, even. Some may want them to fit more closely, so values in the range of -0.3 to -0.05 should work, depending on your settings+filament. We also dropped the model below the plate and printed a couple layers from across the middle to check for clearance before committing to a full print. (See photos below.)
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Scaled up 3 inch version
I was unable to upload files here but STL and STEP files can be found on GrabCAD for anybody interested.
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I used Cura and Horizontal Expansion of -.1 to print on my Ender 3 and they were pretty much free spinning off the bed. The most difficult part was trying to get the first layers to stick to the bed. I had to lower my nozzle closer to the bed than I originally had it to keep the PLA from warping and popping free after a few layers. I printed a few on Prusa MK3 as well without adjusting settings and they were much harder to get spinning, but eventually did spin. They seem to be working great in limited testing (we just decided to use them last week 
)
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Hi Everyone,
We took 2910’s idea and made a few tweaks for manufacturability. We had issues with prints failing on our Markforged Onyx Pro due to rollers pealing up and we had issues with the rollers being so stuck after we printed the wheel that we couldn’t actually use the wheel. We addressed these issues in a few ways:
- We added an extra part that will serve as a brim around the edge of the rollers to help hold them in place
- We sliced 0.010" off the face with the roller flats to get a larger surface area for the rollers to adhere to
- We cut a groove out of the inside of the roller so the roller is only tightly bound to the axle at the top and bottom. The middle doesn’t offer much support but it does have a high risk for welding the axle to the roller.
You can view our geometry via the link below under the 2910/131 VIWs tab.
https://cad.onshape.com/documents/74d55a43d94bc3ac571484e1/w/b22795b79e1dc50d7b776e54/e/d54dbf7ba69f66cf74d20415
These have not seen any field testing yet so use them at your own risk.
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We have also found the easiest way to detach even the most stubborn rollers is to use an adjustable pair of pliers like these:
Set the gap in the pliers to the height of the rollers. Grip the top and bottom faces with the pliers and twist along the axis. It took about 10 seconds to get each roller unstuck on our original print and did so without marring the roller.
What material works best? Think of doing 30% infill ABS. What layer height and nozzle size did you use?
We had good luck with PETG. A good hit to the wall broke a couple, but in real match play I don’t think we broke any. (We ran 1 comp).
Pretty sure we ran them at .2mm layer height with a .4mm nozzle.
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I have updated the design to increase the clearance between the rollers and shafts from 0.007" to 0.015" I have also added a manually designed support wedge to help ensure that the rollers do not break free from the print bed during printing. We have experienced that these modifications make these wheels much easier to successfully print. The rollers spin free without needing to be broken free and the prints don’t fail due to rollers releasing from the bed mid print. Like before these should be printed without auto-generated supports. The breakaway supports are modeled in the CAD model. The support wedges can be cut off with snips or twisted off with plyers.
Left Wheel:
STL 2910, 2in, Preassembled, 3DP, Mechanum Wheel, Left.zip (47.3 MB)
STEP 2910, 2in, Preassembled, 3DP, Mechanum Wheel, Left.zip (684.8 KB)
Right Wheel:
STL 2910, 2in, Preassembled, 3DP, Mechanum Wheel, Right.zip (47.1 MB)
STEP 2910, 2in, Preassembled, 3DP, Mechanum Wheel, Right.zip (686.9 KB)
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Printed 1 on my stock ender 3 in PLA, and it took some force to spin the rollers. Used a pair of flush cutters to remove supports. After they were released, it spins perfectly.
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Just printed one on a MF, didn’t have flush cuts but after removing supports with pliers + filing the burr left over down, these feel pretty close to what our TTB clone wheels with machined rollers felt like.
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brb about to print a few hundred of these. Thanks for sharing @PatrickW, and confirming it works with MF @Knufire!
-Mike
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I am printing the all in one wheel, but I have noticed that the hex opening is a bit too small. How did everyone get the wheels to fit onto the shafts?