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Unread 06-05-2010, 20:15
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Re: Attempting the impossible

Quote:
Originally Posted by CraigHickman View Post
This too can be addressed by Art's words above. It's not the belt, but the usage. Examine why it failed, rather than ditch an entire class of mechanical parts.

Timing belt AND chain have both been done to great success. They also have been done to great failure. Which it ends up being will depend on your implementation, attention to details, and design work.
from experience, chain tends to have always worked, but belts tend to be way too much trouble.

one of our mentors used to be on a wisconsin team (fondy fire). being from there, he told us something we should have followed: "team 93 once tried to use belts. there is a reason why they never have since."

better yet, i found that someone from there said it here on CD on another thread:

Quote:
Belts require a great deal of tension (resulting in more friction) to keep from slipping. Our team used belts a couple years ago and found that the weight savings was not worth the hassle. We have since gone back to chain drive because of its simplicity and robust-ness.

That being said, if anyone out there comes up with a simple, effective way to implement belts in a drive system, I would really like to hear about what you came up with.
source: http://www.chiefdelphi.com/forums/sh...ad.php?t=68479 post #4


reasons to ban the belt from your drivetrain;

1. belts have a lesser surface of contact. therefore, they skip and slip under less torque

2. related to #1, belts are harder to tension as belts stretch at a faster pace.

3. weight- belt sprockets are HEAVY. unless you have access to a CNC or a very precise mill and operator. if not, you will pay a weight penalty.

4. length- chain can be made shorter and longer, belts cannot.


in the long run, it seems that belts are better in high speed, low torque situations. Chain is for lower speed higher torque situations. unless your wheels are <2" diameter, you can almost always count on high torque. and hence why belts never worked for us.
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Last edited by ratdude747 : 06-05-2010 at 20:20.
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