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HP 41 card reader repair question - Printable Version

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HP 41 card reader repair question - DeeVeloper - 09-08-2016 05:09 AM

I am repairing the hp card reader and have found the worm drive gear was slipping on the motor shaft. I removed the worm gear and cleaned out the aluminum tube. Now I need to know
--what can I use to back fill the tube with and
--how do I adhere the gear back onto the motor shaft ?

I tried to use wire insulation to fill the tube but can't find anything that fits.

thanks for any help


RE: HP 41 card reader repair question - wojtek - 09-08-2016 08:14 AM

Not sure if it will be suitable in your case, but I usually apply small piece of cotton adhesive tape and then, after correct centering apply one or two small droplets of epoxy resin to make possible disassembling in the future. Too much resin will make it non-demountable


RE: HP 41 card reader repair question - damaltor - 09-08-2016 08:44 AM

Unfortunately you have already cleaned it out - but for next time: Leave the stuff in there and squeeze the tube a bit with pliers. This will work for ages then.


RE: HP 41 card reader repair question - DeeVeloper - 09-09-2016 04:24 AM

Thanks for the tips.

I did manage to get it back together and it seems to be working again. I used the O rings method on the driven gear and I managed to get some wire insulation squeezed into the tube so the wormgear is working again.

Should be good for a few more years Smile


RE: HP 41 card reader repair question - damaltor - 09-12-2016 02:00 PM

Here is a good way to fix the coupling you mentioned:

https://www.youtube.com/watch?v=qe4jJRJDQbc

(at about the 29 minute mark)