|Repairing the 9820 printer platten -- Thanks!|
Message #1 Posted by Tony Duell on 10 Aug 2007, 1:34 p.m.
I would like to post a public 'Thank You' to David Smith and Katie Wasserman.
Some time ago I asked about repairing the platten roller in an HP9820 internal printer (same mechanism as in a 9810), and they both suggested 3M 'Cold Shrink', a material I'd never heard of before.
Recently I got round to ordering some from RS Components (this is not Radio Shack, it's a large industrial components distributor in the UK). I discovered that the smallest diameter that RS sell is, in fact the same Cold Shrink as the next size up, but the kit also includes a couple of rubber sleeves that you put on first. It's this kit that's ideal for this platten.
After dismantling the printer and cleaning off the goo, force the 2 rubber sleeves onto the original spindle (so that they touch -- a single longer sleeve would be better, but that's what you get). Then clamp the spindle in a vice, put the Cold Shrink over it, and start pulling out the 'support helix'. When you've put about half the length down, cut it round with a knife, slide the remainder over the bit you've just put on, then pull out the rest of the 'support helix'. In the end you have the spindle covered by the rubber sleeves and two layers of the Cold Shrink.
Then all (!) you have to do is trim it to length. I put the spindle in a lathe, and while turning the lathe by hand used a sharp knife, guided by the toolpost, to cut it. If you do it that way, don't even think of turning it 'by power' unless you want bits of knife embedded in you!.
Anyway, the result is a roller of almost exactly the right diameter, which grips the paper well.
Pity I've now got printhead problems, but that's another story..