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Unread 31-03-2014, 09:38
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Re: Belts in a Drivetrain

If you have the manufacturing capability, there is no reason not to use exact centers for belt drivetrains. Absolutely none. It's effective, idiot proof, and reliable. It's not that hard to under tension or over tension a belt, which leads to reduced belt life. I just don't understand how people can prefer tensioners for a system whose tension never needs to be adjusted (in the context of an FRC robot life span).

15mm is far safer than 9mm for a drivetrain. We had poor experiences with 9mm belts and 18T pulleys our first year using the system. Since we've gone to 15mm the problems have gone away for our particular wheel size and pulley tooth counts. This year we used 15mm belts and 24T pulley stock with zero problems.

The bigger the pulley tooth count, the more you can get away with using a 9mm belt in the drive. I'm not entirely convinced yet that 9mm 24T belt drives are a reliable way to do a "West Coast" style drive. Bigger tooth counts should be fine. Any discussion of the strength and validity of belts *must* include the pulley tooth count or else the anecdote isn't useful.
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Last edited by Chris is me : 31-03-2014 at 09:42.