Keeping polycord on track

[LH Machinist]

Use a belt length calculator http://www.durabelt.com/beltlengthcalculator.php
You’ll be surprised about how tight they are supposed to be. The “normal” stretch factor is between 8% – 12%.

[mlantry]

we were having the same problem last night with poly cord.
Is the tension on the bottom alot or just enough and i saw u said u used pref rated aluminum have u tried lexan because thats working well for us and reduced the tension

[Hadi379]

It either looks like you might have too much squeeze on the ball as it travels up your elevator or that your cords are spaced to far apart.

I would try placing some sort of backing behind the cords or I've seen teams use a strip of lexan as a backing with zip tie loops (not tight, just loosely placed) to keep the cords in place.

[jblay]

Your problem might be caused by having so much polycord. The tension of it could be causing the pvc to bend in towards the middle. This would cause lots of jumping. We experienced a similar issue in 09 so we stuck a piece of aluminum L the size of the inner diameter of our pvc through it to straighten it out.

[artdutra04]

Originally Posted by LH Machinist

Use a belt length calculator http://www.durabelt.com/beltlengthcalculator.php
You’ll be surprised about how tight they are supposed to be. The “normal” stretch factor is between 8% – 12%.

In FRC applications, you only need 3-4% stretch.

[Jacob Paikoff]

We just put our polycord on last night and it didn't seem to have a problem. We're using pvc rollers wrapped in shelf liner which creates enough friction that the belts don't move side to side.