Hp-41C card reader - dead

[teenix]

To me , it looks like one end has expanded so you may have used a drill size that is too small and forced the worm gear into the coupling. This may have distorted it. Also, the drill depth is too short for the length of the end of the worm gear. The coupler should butt up against the shoulder.

As mentioned this can be difficult to do at home. The best tool would be a lathe but not many would have one.

Geoff Quickfall also did a replacement using wire insulation but I can't find the link.

Still happy to make a couple and send them to you. That is - a couple of couplers ;-)

cheers

Tony