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+--- Thread: HP 82143A printer repair questions (/thread-17346.html)
HP 82143A printer repair questions - rfdes - 08-10-2021 01:56 PM
Hi -
It was recommended that I post on this site for answers to some questions regarding questions for my printer.
Question #1:
I am trying to find some detailed information regarding a substitute for the flex-cable removal tool (HP T-190579). I see where others have used a thin, stiff, cardboard, etc. in an attempt to duplicate the behavior of the original tool. I haven't been so lucky. Does anyone have more details on the required thickness for the tool to work correctly?
Question #2:
I would appreciate some tips on replacing the rubber roller tires for the paper advance assy. A fellow member has given me a source of square O rings that appear to be acceptable. I am curious if they need to be adhered to the shaft with adhesive or if the friction fit will be sufficient? I've also noted that I believe the original HP rubber pinch tires had an internal groove to slip over the positioning feature molded into the roller assy (see photo). It appears to me that these need to be removed. Any advice regarding this issue would be appreciated.
Thanks
Jim
[attachment=9725]
RE: HP 82143A printer repair questions - teenix - 08-10-2021 04:31 PM
(08-10-2021 01:56 PM)rfdes Wrote: Hi -
It was recommended that I post on this site for answers to some questions regarding questions for my printer.
Question #1:
I am trying to find some detailed information regarding a substitute for the flex-cable removal tool (HP T-190579). I see where others have used a thin, stiff, cardboard, etc. in an attempt to duplicate the behavior of the original tool. I haven't been so lucky. Does anyone have more details on the required thickness for the tool to work correctly?
I use a piece of aluminium soft drink can cut to size and about 30mm long with one end folded over a couple of times to stiffen it a bit and give something to grip. It works well, but make sure there are no sharp edges on it.
This can also get stuck in the socket after the ribbon is removed, so I cut a piece out of one of those disposable plastic food containers of the same size and push this a small way into the socket. This has the effect of opening the connectors a bit and this releases the aluminium and both come out easy.
I wouldn't try the plastic method to try and open the connectors for the ribbon as you won't be certain that the ribbon is released and may damage it while trying to pull it out.
When re-inserting the ribbon, I use the plastic pushed into the fold in the ribbon as it is a little bit stiffer than the aluminium.
Do you have a part number or supplier for the square o-ring. I wouldn't mind getting some myself.
cheers
Tony
RE: HP 82143A printer repair questions - rfdes - 08-10-2021 04:48 PM
Hi Tony -
Thanks for the response. After digging through my 'junk', I found some thin copper clad PCB material that I measured as 0.37 mm (0.015") thick. I lightly sanded the edges and put a small radius on the corners. When I get my O rings and am ready to reinstall the mechanism, I'll try this out. I managed to initially remove the flex cable with a piece of plastic (.77mm/0.030") which was too thick but I managed to get the cable out.
In regards to the 'tires', another member made some measurement of:
OD: 7.86 mm, 0.309"
ID: 5.39 mm. 0.212"
W: 2.11 mm. 0.083"
The part number that was suggested by another member:
AS568-008 SN70 (NBR) Buna-N 70 Duro Square O-Ring
7.83mm OD 0.308"
4.47mm ID 0.176" +/- 0.005
1.68mm CS 0.070" +/- 0.003
These appear to be the closest that I could find so I ordered some from the link below. We'll see how they work out.
[url= https://www.theoringstore.com/store/index.php?main_page=product_info&products_id=4477&fbclid=IwAR1yM-S3Aoy-fVwUW6LrOas4aI5RODnJve7ROmQ5ox_sHkCgiaWCjPpRZ2c] SQ O-ring source[/url]
Take care -
Jim