Re: HP-97 Printer Repair Adventure Message #4 Posted by LHH on 14 May 2012, 4:37 a.m., in response to message #3 by LHH
Curiosity got the best of me and I looked through my life-long collection of heat-shrink tubing. I found some that had rubber-like characteristics and was only slightly smaller than the remaining friction wheels. I used a ball-point pen tip to stretch the tubing enough to slip over the wheels. Then I used a small SMT hot air nozzle to carefully shrink the tubing on each side of the wheels. I started with a very low temperature and gradully increased it until the tubing reacted sufficiently. I worked slowly and only did a small area at a time, cooling it quickly with my fingers between each pass so the original wheel material wouldn't melt. Finally I trimmed the excess with a razor blade. The resulting "recap" actually looks great and the printer is working like a charm again. Only time and use will tell if this is a good long-term solution but one good thing is that nothing was modified with this process so I can always try other methods later if this doesn't hold up. I did take some quick photos of the finished product and will provide a link as soon as I hear back from the administrator about the space I requested.
There are two possible problems I have noticed at this point:
1- The tubing was about 0.010" thick so the wheel diameter is probably slightly larger than it was originally. This will only affect the space between lines so I don't expect it to be too concerning.
2- I noticed the carriage doesn't quite reach the right side when returning to the rest position. It's very, very close and it doesn't appear there are any adverse side-effects but I might move the magnetic sensor if I notice anything unusual.
Other than that the printer is working better than ever (possibly also due to the new NiMH battery), printing clearly and feeding the paper perfectly.
Once I find all my old supplies I'll try the card feeder. That may be the next adventure!
LHH
Edited: 14 May 2012, 4:42 a.m.
|