stepleton
Well-known member
It looks like "conductive/capacitive" text was meant to be a link?
Anyway, since the keyboard is a capacitative keyboard, I'm not sure you want a material that's conductive on its surface, since I don't think you want to short the pads? Although if you are talking about the conductive foam that they pack ICs in, it may not be conductive enough to matter. The easiest way will be just to try it---attach a bit of foam to the end of a pen and use it as a stylus on the bare PCB. I actually wound up using this sort of arrangement to type the 24-byte BLU bootstrap program into Service Mode a few years back :lisa2:
For me, the hardest part wasn't finding materials and laminating them together. Instead, it was the tedious work of pounding out all of those darn little pads, and I think you have to deal with that no matter what kind of foam you use. Now, maybe my punch wasn't the best. I was using a mallet, too---an arbor press or something similar might have been a lot easier!
(For what it's worth, I wound up using a sandwich of metallised mylar film with the nonconductive side out, some kind of HO model railroad trackbed I found recommended on a forum somewhere, and a polystyrene sheet from an art store, all bonded with 3M Super 77. Everything went together in minutes, and I left the sandwich under a heavy book for a day or two to cure. After that---quality time with the mallet and punch. I did two keyboards this way...)
I'll give my usual warning about these keyboards---be very careful about the plastic clip on the caps-lock key. If you take it off, there's a chance that a tiny pin and spring in the locking mechanism will come flying out, and you will be lucky if you ever find those again.
Good luck!
Anyway, since the keyboard is a capacitative keyboard, I'm not sure you want a material that's conductive on its surface, since I don't think you want to short the pads? Although if you are talking about the conductive foam that they pack ICs in, it may not be conductive enough to matter. The easiest way will be just to try it---attach a bit of foam to the end of a pen and use it as a stylus on the bare PCB. I actually wound up using this sort of arrangement to type the 24-byte BLU bootstrap program into Service Mode a few years back :lisa2:
For me, the hardest part wasn't finding materials and laminating them together. Instead, it was the tedious work of pounding out all of those darn little pads, and I think you have to deal with that no matter what kind of foam you use. Now, maybe my punch wasn't the best. I was using a mallet, too---an arbor press or something similar might have been a lot easier!
(For what it's worth, I wound up using a sandwich of metallised mylar film with the nonconductive side out, some kind of HO model railroad trackbed I found recommended on a forum somewhere, and a polystyrene sheet from an art store, all bonded with 3M Super 77. Everything went together in minutes, and I left the sandwich under a heavy book for a day or two to cure. After that---quality time with the mallet and punch. I did two keyboards this way...)
I'll give my usual warning about these keyboards---be very careful about the plastic clip on the caps-lock key. If you take it off, there's a chance that a tiny pin and spring in the locking mechanism will come flying out, and you will be lucky if you ever find those again.
Good luck!
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