[bob1182]

We are using 3/16" solid polycord and it works great. Most teams use 1/4" or larger diameter but we are on a tight budget so we went with the 3/16". We are using 1.5" pvc pipe with endcaps for the 3 rollers and the aluminum rod that came in the KOP for shafts. We use a heat gun to join the ends and 5 % stretch. All this is driven by one window motors mounted directly to the pvc endcap. To guide the cords a volunteer sliced up some pvc connectors to make rings that fit over the pipe. To hold the rings we glued the strips of clear vinyl tubing (with PVC cement). I'm pretty sure we don't need the rings and could just glue on the tubing strips. The system is student built and none of the rollers are parallel with each other. The saying around the workshop now is.."polycord is VERY forgiving".