Roller arm - Wheel

[sgreco]

Originally Posted by ESPbomb

Hello World,
I am in the process of designing a roller arm, which sucks in the tube with tread, and there are mixed views as to one aspect. One party thinks we should have an idle wheel at the back to minimize friction with the frame, and one party believes that if the frame has a curve at the back, a wheel is not needed.
Opinions?

in 2007 my team had pretty much the exact design that you are speaking about. Our prototype had an idler in the back. We built the real thing, left off the idler for weight purposes, and found it made no difference at all. Just make sure it isn't rubbing on anything with friction, and if it is, coat it in any kind of tape you can find with a low friction surface. That's what my team did in 2007, and we had no problems with tubes binding in the back of the claw.

(Just avoid sharp edges, but that's pretty obvious).