HP calculator thermal printheads (HP82143, etc) - test-drb@ccmp.vtda.org

5 May 2000

On May 6,  0:24, Tony Duell wrote:
...
  On Fri May  5, 23:16, Pete Turnbull wrote: 
...
  > > Has anyone here managed to mend a printhead
like this?
 >
 > No, but could you use silver-loaded conductive paint? 
...
  Yes, I'd thought of that (and I keep a bottle in
my tool box).

 Problem is, there's a distinct crack to bridge where the 2 parts have
 been stuck together,so the paint may well not last too well. 
Depends on what stress it might be subject, I suppose.

...
  Worse than that, the printhead is 1/4" wide, and
there are 8 tracks in
 that width. I don't fancy trying to paint that lot without shorting at
 least 2 of them together... Soldering on that pitch I could manage,
 though, if only the solder would 'take'. 
Ah.  Given the thickness of the paint, painting tracks would be difficult,
even with a good-quality fine brush.  The only other suggestion I can think
of, is to paint a wide strip, covering all 8 tracks, and then use a scalpel
blade (and some patience) to gently scratch gaps between them.

-- 

Pete						Peter Turnbull
						Dept. of Computer Science
						University of York