yeah, on buttons, if worse comes to worse, i can make something. i hate to do that, really. perhaps a key, a piece of something conductive under it, a spring or a rubber grommit under the key to build it up, then when pressed the key makes contact.
the more i think about it, the more i''d like to actually use a real keyset for this. of course, in order to do one octave, i need at least 12 buttons. but, i would do 14 buttons, so i can have one inversion and one 9th note. i only want to use it as a lead instrument...
i have not seen a lot of people making keyboards from scratch. circuit ben made one which turned out great! tomommi has a 4 note keyboard in one of his boxes, that is about all i can recall.
of course, i want to circuit bend bass pedals from an old organ too! ;-) i started a thread for that one if you have advice for it...