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HP Forum Archive 18

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HP-97 Printer repair
Message #1 Posted by Karl-Ludwig Butte on 1 May 2008, 3:58 p.m.

Hello all,

I know HP-97 printer repair is an often discussed topic in this forum but I couldn't find any hint how to correct THIS problem: My 97-printer has problems with paper transportation not because of a broken gear wheel but because of worn off gum wheels. The material seems similar to that of the gum wheel of the card reader. Although they're not sticky, they hardened and are now too slippy to have a grip on the paper. Does anyone of you have a hint with what to replace them or are there some special proecedures to make them grippy again ? Every help will be very much appreciated - thank you in advance.

Karl

      
Re: HP-97 Printer repair
Message #2 Posted by Joel Setton (France) on 2 May 2008, 3:46 a.m.,
in response to message #1 by Karl-Ludwig Butte

I had the same problem, and I found that soaking the wheels in water overnight made the problem go away. I hope this helps!

            
Re: HP-97 Printer repair
Message #3 Posted by Rik Bos on 4 May 2008, 8:39 a.m.,
in response to message #2 by Joel Setton (France)

A other method is replacing the transport bar with of a more recent 82162 printer.

Rik

      
Re: HP-97 Printer repair
Message #4 Posted by Karl-Ludwig Butte on 4 May 2008, 2:29 p.m.,
in response to message #1 by Karl-Ludwig Butte

Thank you both for your replies. Because there's no 82162 I guess I'll try putting the gum wheels into water.

Regards

Karl

            
Re: HP-97 Printer repair
Message #5 Posted by Randy Sloyer on 4 May 2008, 7:18 p.m.,
in response to message #4 by Karl-Ludwig Butte

Lightly sanding (abrading) the urethane "tires" works for most problematic units. Restore the roundness best you can near the flat spots.

If all else fails, the 82143A printer is a good parts donor...

                  
Re: HP-97 Printer repair
Message #6 Posted by Karl-Ludwig Butte on 5 May 2008, 3:08 p.m.,
in response to message #5 by Randy Sloyer

Thanks Randy for your contribution - your solution has the charme that I wouldn't need to disassemble the mechanics. Just in case sanding is not enough, is there a good disassemble instruction with photos for the printer mechanism somewhere in the net ?

Regards

Karl

                        
Re: HP-97 Printer repair
Message #7 Posted by Randy Sloyer on 5 May 2008, 4:11 p.m.,
in response to message #6 by Karl-Ludwig Butte

I have done this both ways, both on and off the printer. There are two things you should consider before proceeding:

1) I find you will get a better result by removing the shaft.

2) With the fast solution, one slip and you can destroy the print head.

Complete disassembly instructions can be found in the 97 service manual on the Museum DVD.

                              
Re: HP-97 Printer repair
Message #8 Posted by Karl-Ludwig Butte on 6 May 2008, 3:20 p.m.,
in response to message #7 by Randy Sloyer

Thanks for your additional comments and hints. As soon as I have some spare time I'm going to have a look at the service manual.

Regards

Karl


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