Attempting the impossible

[artdutra04]

Originally Posted by ratdude747

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

How easy or difficult something is to tension does not matter on how fast it stretches, but on the tensioning mechanism at hand. There are very easy ways to design belt tensioners, and very easy ways to design chain tensioners.

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.

SDP/SI sells really nice polycarbonate timing belt sprockets with an aluminum hub. They weigh almost nothing.

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

We design our entire robot in CAD before any final parts are cut, fabricated or machined. Because of this, we design for exact belt and chain paths, and then add in options to tension the system. Belts are no more difficult to design for in this way than roller chain.

we were using KOP belts. kevlar gates timing belts.

Last year (2009) we used the 5mm Gates timing belts on our robot. Never had any issues with them.

as for belts, why use them if chain already works? its not broke, so don't fix it.

Belts are quieter than roller chain at high RPMs, and depending on the application, weigh a lot less.