The Museum of HP Calculators

HP Forum Archive 11

[ Return to Index | Top of Index ]

HP-97 printer
Message #1 Posted by Michel Beaulieu on 31 Mar 2003, 5:54 p.m.

I have a HP-97 in good condition except the printer : It prints whell but the paper don't feed, if i give a little hepl to the paper it feeds normaly but it's not very funny to always do that :-)

What to do?

Thanks Michel

Re: HP-97 printer
Message #2 Posted by Robert Blaschke on 1 Apr 2003, 3:44 a.m.,
in response to message #1 by Michel Beaulieu

Hi Michel,

i made positive experience with the following advice I found somewhere here in an archive:

open the calculator (6 screws), remove the printer carefully (3 screws, lift the attached small pcb) and clean the pin rollers using Q-Tips and isopropyl alcohol (also called isopropanol, available in drugstores / pharmacies).

Be careful when reassembling: do not bend the contacts when attaching the small pcb again; and do not stress the flexible ribbon pcb.

Hope this helps, Robert

Re: HP-97 printer
Message #3 Posted by David Smith on 1 Apr 2003, 5:59 p.m.,
in response to message #1 by Michel Beaulieu

If cleaning the drive rollers does not help there are a few other things to try:

1) Try using a substance called Rubber ReNue (sp?) from MG chemicals. It contains methyl salicylate which softens rubber and makes it sticky. Similar products are sold for use on slot car tires. Keep it off the plastic parts... it will melt them. It helps to use the printer regularly... otherwise the feed cam will harden up and develop flat spots again.

2) With a lot of fiddly work and great care you can remove the feed cam (hint: you first have to remove the print head) and then gently sand the flat spots off the rollers. Then roll the cam rollers back and forth across coarse sandpaper (like 80 grit). Keep sideways tenstion on the cam so that the clutch teeth are kept apart. Clean the rollers with alcohol and/or Rubber Renue.

3) Replace the cam with one from an 82143A printer. Same fiddly mechanical work as above times two... be evry careful reinstalling the head... it can be cracked very easily if it is not seated properly when you tighten the screws.

Re: HP-97 printer
Message #4 Posted by db(martinez,california) on 2 Apr 2003, 1:06 a.m.,
in response to message #1 by Michel Beaulieu

i had the same problem with a former bosses 82143 and it just had a lot of dried lubricant and dust clogging it up. the cleaning that RB mentioned was all that was needed for it. i put a little triflon on all the gear-ish parts afterward and it worked fine. if i wuz u: i'd try this first to see if it works before david smiths more serious treatments for more serious ailments.

Re: HP-97 printer
Message #5 Posted by David Smith on 2 Apr 2003, 6:13 p.m.,
in response to message #4 by db(martinez,california)

Yes, try the cleaning first... but from the sound of the problem it is a hardened or flatened roller problem. Often cleaning will help for a short time... longer if you use the printer regularly.

If the machine was stored for a very long time, the rollers will develop a flat spot where they rested against the paper. This shows up as the machine printer messing up every fourth line. The other problem is the rollers become hard and no longer grip the paper. This causes the mentioned problem where you need to keep some tension on the paper to keep it feeding properly. I have seen people clip one of those big metal paper clamps on the end of the paper and hang it over the side of a table to make the paper feed properly.

[ Return to Index | Top of Index ]

Go back to the main exhibit hall