HP97 Printer Problem

[alejandro3791]

Hi Guys
I have some HP 97, 92 calculators and I have the same problem in everyone :
paper advance problem.
I was changed the gear but the problem comes from the shaft / wheel paper advance.
Could any one tell me how can I fix this problem? Could I get this shaft from any other printer?
Kind regards

[Paul Berger (Canada)]

There are two common problems that lead to indexing failures, the most common is the tires on the shaft have gone hard and smooth so they don't grip the paper, in my case I replaced the tires with similar sized slices of silicon tubing fixed on with a bit of super glue, be careful not to get any glue in the ratchet at the one end. The other problem is the ridge that runs the length of the shaft fits into a slot in the print head carrier so that it acts like a cam that rotates the outer shaft enough that it jumps ahead a couple teeth on the ratchet as the printhead moves to the left and then advances the paper when it returns to the right. If not assembled correctly no paper advance.

This same shaft is used in the 82162 HPIL thermal printer and also the 82143 printer for the 41.

Paul.

[alejandro3791]

Thank so mucho Paul.
I try with te silicone Tunes.
Kind regates
Victor