I've fount that our bumper corners are getting destroyed by the threaded ends of the screws that stick out on the back of the sally port. The worst part is that it is right in the middle of the bumper zone!
Can the GDC just turn the screws around? Robots contact the back of the door much more often than the front, so why don't we put the bumper friendly head of the screw on the side that touches bumpers?
Alternate solution: Drill a 7/8" dia hole where the nut and washer currently sit. This allows the nut and washer to sit on the back of the tube wall that is touching the polycarbonate panel (which I would say is generally a better way to attach things to tubes). The screw could be shorter, so it won't impale our beautiful bumpers!
Other solutions include: rivet nuts or
Barrel nuts paired with
nylon patch screws.
Otherwise, has anyone found fabrics that can deal with the screws?
This is high school robotics for fun and education. Let's try and keep it that way. - Rod [more] 
Threaded Mode