OH SNAP! Belt failures 2014

As the Championships grow nearer, a lot of people (myself included) have been going through design reviews and starting on new designs and revisions for future competitions. A topic that has been brought to my attention in regards to designs have been belt failures. With the new VEXPro/WCP COTS belts and pulleys that recently became available this season, more and more teams have started using belts in the place of chain. Of course with any new product, regardless of how much prior testing it goes through, there will be some unseen extraneous failure possibilities that are found when heavily used that will be fixed in the next iteration of the product.

We (256) snapped two belts this season in our drivetrain from what I believe was a fluke based on examination of the belts and some research on how belts break (the Gates website has so much useful information). That being said, I want to know what failures (if any) that others are experiencing, as well as a decent amount of detail as to the implementation of the belt system.

If you have had a belt or pulley system fail during the 2014 season (doesn't need to be from VEX/WCP - it can be from anywhere), could you please post the following:

1. List where you used belts and pulleys on your robot.
2. List the parts of the robot where belts failed, including how many belts failed in those positions.
3. Describe the different breaks on the belts (ie. clean, perpendicular to the belt, or jagged and messy diagonally, etc.).
4. What do YOU think caused the belt failure? Was it possibly user-error, or a tensioning issue?
5. Did the pulleys ever fail? If so, what size/tooth count?
6. How much load were the belts under? If no numbers are known, give a description and some estimates.
7. Did any of the belts share a pulley with another belt?
8. After using belts, what are your thoughts on them in general?

Also, if you have a picture of the setup where the belt failed, adding it would be greatly appreciated.


This is all for my own information, since I love the idea of belts instead of chain and know they have the potential to work extremely well (see: 971), and want to learn more about correct implementation of them to ensure future success.

Thank you very much for your input,
-Andrew Lawrence