Replacement wood collar for inseam, torso/arm and seat height tools.
The relevant tool needs partial disassembly to replace a collar, and some 2 part epoxy glue.
Once the larger tube is removed, and the old collar is off, carefully remove any glue residue.
Test fit the new collar. It should require a firm twisting action to go on. Remove collar. Mix up some 2 part epoxy glue and apply a 5mm wide band of glue around the top of the tube. Twist the new collar on and continue to twist it to create an even bead of glue around the bottom edge. Make sure the new collar is fully seated. Stand the tube upside down (collar at the bottom) on a firm level surface for the glue to set up.
Reassemble tool. Recheck calibration.
Note, these are made in small batches on an old lathe out of natural wood, then hand finished. Expect some variation.