17 Sep
2013
17 Sep
'13
8:52 p.m.
On Tue, Sep 17, 2013 at 10:13 PM, Ethan Dicks <ethan.dicks at gmail.com> wrote:
On Tue, Sep 17, 2013 at 8:06 PM, Al Kossow <aek at
bitsavers.org> wrote:
I made some for the Keytronics keyboards in a Compaq Portable. I found that
taking thin foam, applying glue to the aluminized mylar (from emergency
blankets), gently pressing them together, gluing the thick plastic discs
(rescued from the old keypads) on the other foam side, and using a
correctly-sized leather punch works wonderfully. You can make a whole bunch
in no time this way. Someone mentioned that Tektronics 4100/4200 terminal
keyboards also use Keytronics switches, but I can neither confirm nor deny
that.
Kyle
I had to fix some Lisa keyboards, and here is
what I finally came up with
after a week or two of experimenting that produces perfect pads.
Woodland Scenics 5mm HO track bed for the foam...
Maudlin PL10-0075 .0075 x 10 x 20 plastic shim stock...
Michaels metalized mylar sheets...
Get a
Disc Cutter with 7 Punch 1/4" to 5/8" from ebay ($28)
http://www.ebay.com/itm/390617394797 for example
This is critial (see below)
I would be tempted to use a laser cutter to make the circles. I think
you could even laminate all the materials in advance and buzz out
discs of whatever size you needed. I know we cut mirrored acrylic
all the time, so thin aluminized mylar shouldn't be a problem.
I would be willing to give it a try if you wanted to send me a few
square inches of raw material.
-ethan