Grease recommendations for worm gear?

[Hans Brueggemann]

(02-07-2023 03:39 PM)John Garza (3665) Wrote:  I started out using Radio Shack multi-purpose lube gel back in the 90's. Works well but eventually dries/dissipates after 15 years or so and must be re-applied.

I really didn't think much about the grease until...
I recently bought a 67 with a refurbished card reader. I noticed the card reader was a little quieter than the repair jobs I do. That impressed me. What didn't impress me was the number of misreads. Then I noticed a pattern - after 5 or 6 passes of the card through the reader it was suddenly reliable on every read. I suspect they used a thicker grease that made it quieter but needed a little 'warm-up' through the gears to reduce viscosity. Any ME's out there care to consider this?

no, this is not about warming up, it's the worm gear breaking free by "combing out" clogged debris and dust. also, the motor shaft requires some tiny amount of "play" (approx. 0.5 mm) in the lateral direction after the gear has been re-installed.
another reason for a louder than expected reader is a too tight adjustment of the excenter pin. you can try and test it by giving it a quarter turn in either direction and redo a test run with a card.
when repairing the cardreader, it is a good idea to thoroughly clean the gear from old grease residues before applying new grease. stay away from mineral greases, as they might deteriorate the main gear wheel (never experienced that on my repairs. however, better safe than sorry).
i'm using ÄRONIX 6900 PTFE paste for all repairs, which is known for not deteriorating materials like nylon or delrin (among others). not sure as to whether that is available outside of germany, though.