--- On Sun, 4/3/11, Mike Loewen <mloewen at cpumagic.scol.pa.us> wrote:
???And an emergency mylar blanket from
WalMart.
???I used 5mm track bed foam from Woodland
Scenics, available at your local hobby shop.? The
resulting pads are a little stiffer than the original, but
perfectly usable.? I used the original plastic discs
(after cleaning them), and glued the mylar, foam and plastic
together with Elmer's Rubber Cement.? It's tedious, but
it works.
I used a roll of foam rubber weatherstripping from the hardware store - I found one that
was the correct thickness, I'll have to look for the brand name and part number.
For the conductive side, I used a cut-up antistatic bag, and for the plastic side, I used
some thin flexible plastic I found somewhere - but I'm sure a transparency film or
similar would work - the stuff I had was only slightly thicker.
The foam I used was self-adhesive, so I stuck that to the plastic backing first. Then I
used 3M spray adhesive to coat the top of the foam (it's only self-adhesive on one
side), and glued down the anti-static bag. After that, let it dry thoroughly (otherwise,
the glue sticks the foam together and holds it compressed). Once dry, I punched out lots
of little foam discs and populated the keyboard. Tedious, but not too bad. I had better
results punching if I punched from the mylar side than from the plastic side - but it
could have just been my punch/material combination.
It takes a couple hours, but it's worth it to have a functional keyboard. Again, the
foam I used was slightly stiffer than the original stuff, but it worked great. The
keyboard I rebuilt in this manner was for a Franklin Ace 1000, but I've tested the
discs in other keyboards and they work fine. The Keytronic mechanism seems to be the same
across the various keyboards.
-Ian