re-use of these proprietary nightmares is possible, but intense and tedious.
i use those tiny pushbutton switches to replace the "gone-bad"
carbon/membrane buttons.
membrane hand controllers are nasty short term junk, made to give the
factories endless job security. i hate them.
you may break the carbon, just scribe through it with a pointy object enough
to break the route.. they do not solder, tried again and again many, many
ways NO DICE. no flux or other joins carbon and tin unless you heat it to
about 2000 degrees, but then you end up with an entire carbon pile of junk
anyway.
you may subvert this problem by using something called "Nickle Print" or
some name like that. it is a paint like conductive stuff in a 2-3 ounce
bottle, abt $5-10 buks US dollars. GC electronics, (its not Walmart
stuff), go to a real hobby shop, electronics shop, or EBAY!
http://www.abra-electronics.com/catalog/chemicals/22_201.html
i use that silver plated Kynar wire for prototyping ( wire/wrapped) for
point to point. clean the carbon you want to connect to, strip about .0625
inches (1/16) of insulation from the end, put down a pinhead spot of the
nicklepaint, secure the wire with tape or better, use hot melt glue to
secure, do NOT glue over the paint, it MUST dry BEFORE you use it! most
times it works 99 percent of the time, otherwise you usually put another dot
of nicklepaint on it and dry, other wise, start over. PREPARATION is the
key to success here!
at purchase, immediatly dissasseble them, get to the point between the
contact and those shitty carbon dots and spray some real silicone
lubricant, do NOT use the silicone crap found in Auto supply stores, that
has petroleum product in it that will ruin the menbrane. better yet get
some fuser silicone lube from someone who has one of those monstrous Office
max or Copy Max or Staples duplicating machines. that comes in huge
bottles, they always throw 10 percent away each time they refill.
its gooey, sticky, but it never dries or ever migrates. it displaces
moisture and keeps the switches perfect for YEARS! but you will never be
able to paint anything it touches either.