Okay, as an offseason project, part of 1072 is making a mecanum drive.
first part (and probably the hardest) is the wheel.
here's our scheme for making one.. we'll make at least one over this break (its spring break for us) and report back how it is.. but if you see any glaring problems, please post asap.
Tools -
A Mill (Bridgeport in our case)
1/4 in end mill / drill bit
1 in , 3/4 shank end mill
Clamp set
Indicator
Vise
Edge finder
Materials -
3/4 plate 6 in x 36 in
Lab-stops (Mcmaster - 9545K15)
Generic 2 3/4, 1/4-20 bolts
1/4-20 nuts
retaining rings.
First, Take the plate, cut into 6 plates of 6 in x 6 in.
Next, bring to our friendly machinist, and have him turn the plate into the following pattern..
http://i27.photobucket.com/albums/c1...3456/Part1.png
Now, take back to the brigeport, tilt the head 45 degrees, and true the vise.
Then after we have that, we can just vise the plate using the octagon.. that will ensure true-ness on one plane (ie the y is now true) and then find the center of the octagon, and then use a 1 in endmill, then a 1/4 in end mill through to get..
http://i27.photobucket.com/albums/c1...3456/Part2.png
Then, since this form is quite awkward, after tramming the head to 90, we make some ornamental cuts.
http://i27.photobucket.com/albums/c1...3456/part3.png
Now there's the hub, the rollers should be equally easy. originally, we were planning on begging for someone with cnc lathe to cut us this profile..
http://i27.photobucket.com/albums/c1...3456/Part4.png
But, our student mentor realized that a lab stop, bored with a .25 in hole would be nearly identical in terms of circularity (the one and maybe even only key measure of wheel performance)
here's comparison of theoretical optical versus lab stops
http://i27.photobucket.com/albums/c1...3456/Part5.png
Finally, it should look like..
http://i27.photobucket.com/albums/c1...3456/Final.png
So. Any suggestions, comments, concerns?