Card reader other problem :-(


Thanks! i fix the "non" detection of the card with your tips... But now i have notice when doing the job that the rubber wheel is slowly getting... liquifying and leave some trace on cards. I read about replacing the "material" with o rings? what size is best; my wheel is smaller that original and don't know about "real" size it's suppose to be.

Is there another material for the job? if not, how many o rigns to add?

Thank you


Ok, that's it. Just chuck it and buy a used TI-59. Now that's a REAL machine ;)



Look in the articles section. I know there are articles on replacing the wheel in the 67 and 97 and I'm pretty sure there is info for the 41C card reader. For the 67 and 97 there are two ways, O-rings or silicone tubing. I've done the silicone tubing on my 67 with no problems. Sometimes tubing doesn't have a uniform wall thickness, O-rings might be made to better tolerances. Also I can see how the round cross section of O-rings would make this method more tolerant of variation. I understand it is necessary to glue the O-rings, which is not required for the silicone tubing. Also, I wonder about the mold "flash" around the circumference of O-rings I have seen. Does it rub off after a little use? I don't know, but I'm going to try the O-ring method sometime.


It is not necessary to glue the O-rings. The size is 006, or the ones that I use are 1/4" OD, 1/8" ID. The 005 also works. Most hardware stores carry o-rings.


EVERY size 006 ring that I have seen is too big, and I have them from over a dozen sources. The size 005 is very hard to find. I have also seen problems with the O-rings wanting to slide apart (you need to use two of them) and drag on the sides of the mechanism. I prefer the silicone tubing, but finding nice, round, concentric tubing can also be a problem.



well, here in Brazil is somewhat easier to find them. In fact, I was given some O-Rings that were easily found in a (believe me) car´s maintenance garage. They are found in old carburators, as used or replacing, spare O-Rings. I have an 82104A working with two used O-Rings (I just cannot find my cards´ pack... I only have two cards for testing, and they run a lot good) not glued to the axes. Dave, I did not measure the O-Rings, I simply inserted the two (same) that fit in the same measure of the axes (inner and outher limmits). They are still there and running smoothly.

Hope it helps.



Using CAR parts to fix your 41- now I've seen it all.

John Kercheval


Yeah! (but don't remind me, please...)



And for $20 you guys better take Ty up on his repair! How you doing Ty?



Doing good. Thanks Dave.


I would be happy to supply o-rings to the less fortunate ones who cannot find them. Price is $1 for two o-rings and mailing(in the USA). I also fix card reader drive wheels for $20.

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