Hello folks,
did anyone suceeded in repairing traces on that old plastic sheet printed circuits keyboards? Some traces are interrupted and it's impossible to solder on that kind of plastic/trace combination. I've had some success on plastic substrate when the tracks were copper strips of sufficient thickness, but in this case they looks like black conductive material and the plastic substrate is so thin that any tip at a useful temperature for soldering instantly makes a hole. I've been thinking about conductive glue, but it might not stick or make a good contact. So if anyone already had experience (positive or negative) is very welcome. It's a 30 years old mitsumy custom keyboard, so not replaceable with something modern. Thanks Frank