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Unread 02-12-2014, 10:28
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FRC #0228 (GUS Robotics); FRC #2170 (Titanium Tomahawks)
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Re: Fitting belts within your frame

Quote:
Originally Posted by Joey Milia View Post
Something I'm missing here? 192 runs 22t gt2 pulleys and 15mm wide belt in 2x2in 1/8 wall tubing. Maybe it's the lack of flanges...
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?

Quote:
I designed the whole thing up with 3x1.5 and it weighed ~44 lbs all said and done with the 3 CIMS and shifters (minus control system), which is pretty beefy. Moving to 2x1.5 I could save a few pounds, and since that's still structurally sound it seemed like a good way to lighten the base.
This is the same ballpark we were in last year. Honestly, a 44 pound drive base, complete, is not that bad. It's not crazy weight efficient like the world's best west coast drives and sheet metal frames, but if your manipulator weighs more than 70 pounds you've already messed up.

I'm curious about moving to 2x1.5 and using 22T pulleys, if it works for 192 it is something we might try next year. 3x1.5 tubing is definitely a compromise for us. We briefly explored using 2.5" tall tubing last year to try and save weight / make 4" wheels more viable, but once the game came out and the floor was perfectly flat we decided there wasn't a good reason to try something new.
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Last edited by Chris is me : 02-12-2014 at 10:34.