Fitting belts within your frame

[Joey Milia]

Originally Posted by dellagd

I was referring to not being able to move up to a 24T pulley, which is the next biggest size vex sells. I was hoping to use their pulleys as we've ordered from them before and they already are set up for hex shafts. The flanges dont help though, removing the flanges would make it really close if not hitting still with a 24T. If you have another supplier for 5mm HTD Hex pulleys I would you be willing to share? I know you said GT2, but were invested in HTD now, so it would be nice to stay standardized. If they aren't hex broached yet I think we could figure that out too.

If you're looking for a mostly COTs option our set up might be a bit difficult. We buy pulley rod from SDP-SI and cut it into 1.5in pulleys before doing the bores and broaching ourselves.

Originally Posted by Chris is me

Sorry, I was assuming that rivet clearance on both sides of the frame was desired. It's also been a few months since I've done the math on pulley + belt OD. Thanks for the correction and information. Do you guys weld everything, or offset your rivets so they are on the side the belt is not on, or something else?

22t is the absolute largest you can fit in 2in 1/8 wall tubing. We offset the baseplate rivets from the belts and we do the center drop by pushing the outer wheels up 1/16 and the middle wheel down a 1/16th. I think if you did it all from just the center or just the outer you would get some rubbing. Going 3/32 either side of center to get 3/16 total should be possible though. (please check in CAD though I haven't looked at it for a while)

We chose to go with 2x2 instead of 2x1.5 because of how tight the belts are in the tube. 1.5 doesn't leave much room for things poking into the side of the tube (like gearbox bolts or the caps for access holes) and we were worried about rubbing the sides of the tubes. How well does your set up work with 1.5in wide tubing?