Discussion about the Korg PolySix synthesizer

Hi Andrew,

Are you sure there would need to be a replica made? I thought it may be
possible to replace these with a standard part from a modern keypad, or
similar. This type of contact pad is still used a lot. It may not be
easy to find these for small quantity sale (of course, 10,000 is a
different matter). Existing parts would not likely have quite the right
dimensions, but I doubt the dimensions would be too critical (I think a
little narrower radius, thicker or thinner would all be fine).

In the next couple of weeks, I will meet with the supervisor from my old
job, who gets keypads made for HF radios. His rubber keypads come as a
single piece, to his design, from an outsourced fab plant. He may be
able to give me some pointers for this (though maybe not). I'll post
back here if I get a result.

BTW, IIRC, these pads are rubber, with a coating of conductive silicon
or metalised powder adhered to the surface. As the conducting layer
would only be a surface treatment, I imagine that one could wear it out,
or accidentally clean it off. Has anyone had experience with this?

My keyboard has been bad for years, and I haven't yet found a
satisfactory solution. I haven't felt like buying one of the not so
cheap re-coating compounds. I'll try the lighter fluid next time I open
the synth.

Cheers,

Oli

On Sat, 2009-02-21 at 23:09 +0000, Andrew Jury wrote:
> Ha!
> 
> Just don't let anyone ever smoke near it! Only joking! I had a very 
> intermittent Polysix keyboard in a while back and no end of using IPA 
> would make a great deal of difference to the contacts. I ended up using 
> this stuff:
> 
> http://uk.rs-online.com/web/search/searchBrowseAction.html?
> method=getProduct&R=2638089
> 
> This is, used in the right amounts, seems to be a good solution for 
> cleaning both the contacts and PCB pads. It's the type of thing you 
> would normally use on high voltage switch gear and the such like. The 
> keyboard is now still working about 5 months after it was last 
> serviced. I think, like you have noted, sometime you just need 
> something a little stronger than IPA. In this case it is a trade off 
> between something that works without causing any damage or so strong it 
> starts dissolving things. 
> 
> I wonder if we took a set of these contact pads to a component 
> manufacturer and asked then to build a replica what the minimum 
> production run would be to make it a viable task. If we had 10,000 made 
> I'd bet they would all sell!
> 
> Cheers,
> Andy
> 
> 
> --- In PolySix@yahoogroups.com, "wasteking1" <wasteking1@...> wrote:
> >
> > the last time i cleaned my key contacts i used alchohol and a q-tip, 
> > but the results didnt last and were inconsistant. Some notes 
> > were 'sluggish',almost had a delay, others had to be hit multiple 
> > timrs......   So I recently cleaned them again, this time using 
> LIGHTER 
> > FLUID  (ronsonal)  and a q-tip. I was very careful not to get the 
> fluid 
> > on the laquer of the pc-board, Interestingly, i got a black residue 
> > from many of the round magnets on the q-tip,(but not all) .  i NEVER 
> > got any signs of  residue using alchohol. Now the keys work great, 
> all 
> > instant contacts, no sluggish response. Perhaps this stronger solvent 
> > is more effective?  seems that way to me.
> >
> 
> 
> 
> 
> ------------------------------------
> 
> PolySix "Digiest" Page: http://www.acc.umu.se/~amber/Poly6Yahoo! Groups Links
> 
> 
>