after considering advice from others on the manufacturing of the mechanum wheels, i designed another one, 3.7 LBS a piece and holding up to 200 lbs per wheel.
I’ve been following your design process through what you’ve posted, and I must say that I’m impressed. Your rollers look fantastic. I do have a few questions though. What kind of bearings are you using in your rollers? I couldn’t tell from the images. I like your plan of having rollers 3D printed and plastic coating them from there, how do you plan on doing that? I’m guessing that means the cores of your rollers will be made of a hard plastic, that being said, how thick of a tread are you planning to put on? Are you putting any kind of scoring or surface area creating patterns to keep the outer rubber from delaminating? Keep it up, I can’t wait to see these wheels on an FRC Field.
each roller has an axle which is .5 inches in diameter, however the last 3/16 of that axle will be turned down to 1/8 inches in diameter. on the fat edge of the roller a 1.125 od .5 id bearing will press fit in, on the outside a .75 od, .125 id bearing will fit in. as part of the new design, the rollers will not be printed, however we will print a mold, for urethane casting. our printer has a resolution of about 1/64 of an inch, so the rollers will have the texture of 60 grit sandpaper in theory. i may add a little more texture too before printing. the last thing to add is rubber weather coating. it is sort of spray on rubber, designed for protecting patio furniture. it is incredibly tough, and creates a very thing coating which should give the rollers a tiny bit of tread.
as always, any comments are appreciated, these might be built the coming season, but definitely will be built the following season.