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Electrically conductive clear resin or additive? Answered

I'm looking to craft some tiny 2mm buttons for a smartwatch face plate. I've got the design down, but I can't get the screen to register the presses. After some digging I learned enough about touch screens to know why.

The buttons are going to be cast in a clear orange resin designed to pick up light from the screen below them. Does anyone know of a clear additive or resin material that can sufficiently conduct electricity over a distance of no more that 5mm?

If you have any scraps of clear white or clear orange resin. Try using it as a stylus on a smart phone or tablet. If the screen registers the press, let me know please!

Also, first time posting here, so bare with me if I have overlooked any sort of etiquette. 


option: coat edges(not top n bottom faces) of buttons with conductive ink or paint. There is silver, and black, in my experience. Doubt that such a small quantity would have enough capacitance to "trigger" the touchscreen, but maybe it will link screen to capacitance of your bod.

Touch screens dont work by conductivity, exactly. At least not conduction from screen to finger. Capacitance is the key. Wrap your finger in saran wrap. It still works on touchscreen despite electrical insulation. Salt water in plastic wrap also works. Perhaps saline gel in a very thin skin will suit your purposes.

If you're looking a quick answer for testing a very fine sandpaper should rough the surface enough that you can use a soft pencil to coat it with graphite from the pencil.

In fact depending on the sensitivity of the screen you might be able to just rub it on the plastic and preserve conductivity.

i tried this immediately after posting this thread. lol

I used both mechanical lead and a cheap #2 pencil. The item didn't work. I'll retry after sanding though.

It's worth a shot - I've had luck along a similar line before - a quick test with bits of paper seems to be showing softer pencils as more reliably producing touches, I'd guess that there's less clay to graphite in them.

This could work if they did the liquid, but the info at the bottom suggests they sell the panels of material treated already.