I posted something on my blog regarding how to make a silicone rubber sheet that works perfectly.

You can find it here http://www.multitouch.nl/?p=38

I’ll probably start posting more details later on.

edit:

I posted some more details now, located here: http://www.multitouch.nl/?p=43

Today I’ve poured my own silicone directly on a 1,3 x 1m acrylic surface.
I’ve used the same brand (Elastosil) as Gravano has used (bought it in Holland at http://www.hazelaar.nl an arts supply shop in Soest, 1kg is about 35E without taxes). I’ve used about 2kgs, just to be sure I had enough (at the end I think I had 0,5kg left stuck on the floor, hehe)
It was a little nervewrecking to pour a 100 Euros over the acrylic but in the end it became as smooth as a babies bottom and amazingly transparent (its almost invisible)!!

O something to know for all you future silicone users:

I’ve heard that silicone stops hardening if it’s in contact with a metal. I haven’t experienced this myself but I took the advice as a warning and used Polystyrene for making the mold to keep the silicone within. Wood would also work as long as it isn’t metal.

Well hopefully tomorrow I have a perfectly zero force sensitive table!!!

Gr Ajen

k cool, i hope it works out fine, mine was also very smooth and transparent as hell, we used a metal strip like shown on the pictures on my blog to flatten the silicone rubber and make a nice smooth flat surface, so for us there was no problem while curing the silicone rubber eventho we touched it with a metal, but like Arjen suggest, I wouldn’t try it with a metal again since it says so on the label. We touched the silicone rubber with the metal briefly and the curing wasn’t done within a metal frame, so maybe that’s the difference.

i have just found this site http://www.aerorubber.com/hose.htm it looks like i can get a silicone rubber sheet at how ever thick i want it is it really that good is it different than the ones your guise made i will probably ask for a sample first but it would be grat to have your opinion on this

new guy here… just curious why is a silicon rubber sheet used?? and under what circumstances/types of multi touch surfaces do you need it

It does two things:
-Provides zero-force touch ability.  Also, things that are not moist (like a stylus) can be used with a compliant surface if desired.
-Gives you the ability to project onto the table without diffusing the touch.  If you put, say, a piece of mylar behind the acrylic instead of using a compliant surface, you wouldn’t be able to get defined blobs (which would hinder apps like painting).

what thickness worked best? 1mm or 2mm. im thinking the thinner the better?

correct 1mm worked better for me then 2mm, 0,5 might probably be even better