Team 4055 had a problem with tensioning our catapult. I don't know exactly what is a problem with yours but we had a few issues.
1) We had one CIM tensioning the catapult
2) There was a large amount of friction because we didn't use bearings (Bad decision)
3) We were applying force to our arm at an extremely small angle.
Fix
1) We designed a completely bolt on mechanism. It was a 4.5 to 1 ratio with two CIMs.
2) We upgraded to a 1/2 in keyed shaft with Oil Impregnated Bronze Bearing
http://www.amazon.com/Spyraflo-PB1-5...bronze+bearing
3)Force has it's maximum efficiency when the force is applying perpendicular to the arm. Relocating our attachment point for our winding strap helped.
