Flexible PCB rewiring
I'm working on a project where I want to strip a 'roll up piano' down and take the rubber keyboard innards which feed into the electronic sound unit and get rid of the floppy rubber roll up piano keyboard and replace it with a standard PC qwerty keyboad. I got used to using a qwerty keyboard for playing tunes already and want tomake one that is stand alone that I don't need to connect to the PC to play music with. That means I need to take all the connections that you can see in the photos I uploaded and re connected each one to a key on the keyboard.
First of all, I don't know if pressing the rubber key on the roll up keyboad 'completes a circuit' and therefore prompts the electronic unit at the end of it to play the sound or if it 'breaks the circuit'. These units have two flexible pcb sheets as you an see in the second photo so when the rubber key is pressed they touch (although they all seem to be pretty much touching anyway). In an old casio solid keyboard I have there is a hard pcb and the piano keys touch a small rubber disk (much like is what under qwerty keys) to the pcb.
would it be better for me to take a razor and painstakingly slice up the flexible plastic which the pcb is printed on then lead them to the innards of the qwerty keyboard I'm going to modify or would it be better for me to just chop the flexible pcb off and use some kind of very thin coppe wire to feed dirctly into the unit and to the underside of the qwerty keys?
Any guidence would be appreciated.