Concerning an easy interface to 8" pneumatic, when I used them last (with 2849 in Columbia), I made two jigs that allowed the kids on our team to make the modifications necessary to attach a sprocket using only a drill press. One jig help modify the plastic hub, the other modified standard AndyMark sprockets (Andy, why don't you guys put in a mess of additional hole patterns in your spockets to facilitate such monkey business? -- it easy for me to say but I think that you could do it for essentially no cost)
Anyway, my problem is that I've moved twice since then and I am not sure I can put my hands on it. Plus the end result was heavier than I'd like.
This year, my proto chassis is going to use the wheel in the attached photo* I plan to use dead axles (and you probably should too -- unless you have really good reasons not to) and the as shipped standard hub (with my kluge attachment of drive sprockets).
If I use them on our competition robot, we will likely do something else. This AndyMark hub sounds interesting, but if I don't like that, I think I can make a much lighter 200X50 hub that is something akin to IFI's hubs. I would plan on using AL side plates spaced apart by standard plastic spacers from McMaster. These spacers would form the ID of the tire bead. I will encircle these spacers with a thin AL strip that will support the ID of the tube (Strip: 0.032 thick roughly 50mm by 650mm ~ pi X 200mm + 20mm overlap). ... I think it could be light, strong and ... awesome.
But... The devil is in the details.
I should CAD this up and post it. Stay tuned.
Joe J.
*You can buy these from mobilitydirect.com (no ties financial or otherwise) they are not "on the menu" but you can order them just the same see my correspondence below:
Yes we do sell these.
To order please give us a call at 877-914-1830.
Refer to part #080200-3-4
Description: CASTER, 8 x 2, 4-HOLE 2-PIECE RIM, KNOBBY PNEU TIRE, 3/8" PREC. BRGS
Price - $34.65ea
Ron
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