1. Remove the four wingnuts underneath the corners of the cushion ("A") to remove it.
2. Use a Phillips-head screwdriver to remove the four screws at corners of the Insert ("B") to remove it.
3. Take note of which roller is lower. That is typically the one where the gear slipped. Unlock the rollers at location "C" so that the rollers can rest at the bottom. The handle should be pointing toward floor.
4. Locate the spur gear for the roller that is out of alignment. Use a 1/8" hex wrench to tighten the set screw securing it to the shaft. If the set screw is rotated toward the floor then grasp both rollers in your hands at the same time and lift the rollers while watching for the set screw to come around to an accessible position and then tighten the set screw.
5. Replace the Insert and cushion.
