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82143A Thermal Printer repair - Printable Version

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82143A Thermal Printer repair - 4ster - 11-08-2017 03:39 PM

I am about to open up a 82143A printer to see if I can get an intermittent paper advance problem resolved. The only thing I have been able to find was a recommendation of a TEAC tape drive roller product to restore the "stickiness" of the roller. I also found a discussion about how to remove the ribbon cable from the board, something I hope I don't have to do.

Is there a tutorial similar to the roller repair for the card reader? Nice to have information before going in.


RE: 82143A Thermal Printer repair - rprosperi - 11-08-2017 07:20 PM

(11-08-2017 03:39 PM)4ster Wrote:  The only thing I have been able to find was a recommendation of a TEAC tape drive roller product to restore the "stickiness" of the roller.

You can use generic rubber treatment products like this one, it isn't necessary to use the typically more expensive audio cleaning products:

https://www.amazon.com/Max-Professional-2145-Rubber-Rejuvenator/dp/B00363M0TC



RE: 82143A Thermal Printer repair - 4ster - 11-09-2017 01:00 AM

Thanks for that.

I tried the printer again today and got it to start a CAT 1. Previously it just returned "PRINTER ERROR" after sounding like it was struggling to print. This time the paper advance seemed to work, but it was struggling to print a line of text. After printing 5 or so lines of a Cat 1 (which were spaced correctly) it stopped and the 41 displayed "PRINTER ERROR".

I've not opened one of these up. Does the print head carriage get gummy over time?


RE: 82143A Thermal Printer repair - aj04062 - 11-09-2017 01:17 AM

The drive wheels don't really get gummy like the card readers, but they do dry out and then are toast.

I tried a lot of different things to rehab, but the best solution I have come up with is to replace the drive wheel with a square o-ring. Superglue it on and it works great. You usually need to clean up some of the grime inside as well and lightly lube the mechanism and rods that parts slide on.

Adam


RE: 82143A Thermal Printer repair - Dave Frederickson - 11-09-2017 02:19 AM

(11-08-2017 07:20 PM)rprosperi Wrote:  You can use generic rubber treatment products like this one, it isn't necessary to use the typically more expensive audio cleaning products:

https://www.amazon.com/Max-Professional-2145-Rubber-Rejuvenator/dp/B00363M0TC

What's this about not being for sale on Catalina Island!? So much for my plans to retire and move to Avalon if I want my rubber rejuvenated. Sad


RE: 82143A Thermal Printer repair - rprosperi - 11-09-2017 02:59 AM

(11-09-2017 02:19 AM)Dave Frederickson Wrote:  What's this about not being for sale on Catalina Island!? So much for my plans to retire and move to Avalon if I want my rubber rejuvenated. Sad

I missed that, otherwise I would have recommended a more widely distributed product. Last time I was in Avalon (quite a few years ago, so things may have changed), there were plenty of creaky old machines that could have used this stuff too. They must like them that way...


RE: 82143A Thermal Printer repair - 4ster - 11-09-2017 04:35 AM

The problem seems to be related to the temperature of the printer. Tonight I got it good and warm on the mantle of the fireplace. It ran perfectly. It was about 40 degrees F when it didn't print at all.

I think the problem is the guide rod and the screw that moves the print head.
I assume that it only needs a cleaning.

If I had no guidance I would clean with alcohol and lube the screw and guide rod with a dry teflon lubricant. Is that about right?


RE: 82143A Thermal Printer repair - 4ster - 11-09-2017 01:55 PM

Outcome: There was some black stuff on the guide bars and the positioning screw. There wasn't much, but it was dry and "un-slippery". Apparently, the residue increased the coefficient of friction as the printer got cooler. I cleaned this off with alcohol (actually hand sanitizer since I couldn't find the alcohol last night). When that had flashed off, I applied dry teflon lube to the moving parts. I also noticed that the bearing on the optical encoder side of the screw was out of position so corrected that as well. And, I didn't have any parts left over when done!

It works! I think the print speed increased after cleaning. Now I have to see if it works better after it gets moved to a cooler location.


RE: 82143A Thermal Printer repair - Duane Hess - 11-09-2017 02:49 PM

4ster:

May I ask what brand of dry teflon lube you use?

thanks?


RE: 82143A Thermal Printer repair - 4ster - 11-09-2017 03:05 PM

Please understand, I guessed that using dry Teflon lube would be a good idea in this application. I don't know that it is.

I used Finish Line brand "Dry Teflon Lube", a bicycle chain lube. The product was purchased at a bike shop. It comes in a bottle with the Teflon suspended in a volatile carrier. When the carrier evaporates the Teflon remains as a lubricant. The supposed advantage is that dirt is not attracted to the lubricant as it is to a grease or an oil. That is my theory anyway.