Archive of the former Yahoo!Groups mailing list: Discussion about the Korg PolySix synthesizer

Well the first unit appears to be all working properly. I had to skin one contact a bit since I got some shorting where I had to tap the key to make it stop sounding the note. I suppose it's possible that cup was just out of tolerance.

When I first put them in a few developed intermittent performance like a dirty contact. But I know they aren't dirty. I tried scrubbing the gold contact with cleaner and that didn't help. I replaced the contacts and that resolved the problem. So I'm thinking that maybe they got warped in the cutting procedure and we just had to retry.

The key to success here I believe is going to be refining the cutting tool and perhaps we can just sell these as kits where people cut with a tool that is supplied and their own hammer on a hardwood surface. Then the tool actually fits over the contact which has adhesive backing and then they push it on with a plunger tool so that it's centered. Then pull the tool back and pinch the cup and roll the contact down tightly on the surface and there we have it!

Anyway I'm going to recommend that people only put half the screws in and test the thing first. If all seems well then finish putting in the screws. If for some reason a contact doesn't work just redo it, making sure any impurities are removed from the area and that the gold is clean also. I had to redo about 6 of the 61 contacts to get perfect performance. So I'm thinking it has to do with having to pull them away from the material because I didn't quite get them cut through etc. Once the process is consistent I see no reason why they shouldn't work every time since the material seems homogeneous enough. But so far replacing the contacts that are bad gets us to a perfect functioning keyboard after the initial install. -Bob