I've fixed a couple of keyboards using hobby shop track bed foam, but have
not been very happy with the "feel". That foam is considerably less
resilient than the material Keytronics used. After trying a number of
alternate materials, I have found something that is almost identical to
the original. Take a look at eBay #171549720453 for an example.
It's 5mm thick with an adhesive backing, sold for shoe inserts. I stuck
0.075" plastic sheet to the backing, then turned it over and used spray
adhesive for the aluminized mylar. Worked like a charm. Just finished
resurrecting a N* Advantage and the typing feel is (in my opinion) far
better than the last unit I did with track-bed foam (Corvus Concept).
Steve
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