Fabulous new silicone

Antenociti · Post by **Antenociti** » Mon Oct 16, 2006 1:01 pm

Our silicone and resin supplier has sent us some new addition-cure silicone to test: and its bloomin' marverloooous.

It hasn't got a name yet, and its not available for a couple of months but:

Its a 1:1 mix (by weight or volume) and this stuff is T.H.I.N.
I kid ye not it is virtual self-de-gassing.

Standard cure time is 14-16 hours, pot life 30 mins, but there is also a "hot" mix variety that has a 3 minute pot life and 10 minute cure time.

Importantly this stuff is oil-free, so its very different to most normal silicones and it does, in theory, also resist resin attack much better than oil'd silicones. Testing it so far without any mould release and am on cast 14 without any noticeable dryness or cracking.

Does it take fine detail? Blimmey, does it!
Its so thin that it seeps between the cracks in my mould blocks. Normally just pressing them tightly together is fine, but this stuff find the cracks. It also ALWAYS creeps underneath the bottom of blocks (lego etc) unless you weight them down or fix them some other way.

Indeed the "thinness" of it is almost a draw back as it will get under anything that isnt perffectly flush and completely sealed: I've made some (fantasy) door moulds with it and it creeps between the door handles, hinges and down and under planks etc.

Now as its thin you;'d expect it to be weak and tear easily? It doesn't. Shore A is 30 from specs iirc (might've been 20 though - i'd need to check with supplier) and it feels very "plastic" like without any oilyness to it like normal condesation cure silicones. Its very smooth, deep blue and lubberly.

I cast some normally and chopped the resultant moulds in half to find bubbles - couldn't find any at all (seriously, chopped it down into tiny pieces and coudln't see a buble anywhere at all).
Twisting and pulling didnt result in tears either (usually a good sign of micro-bubbles).

So - anything bad about it?

Yeah - it costs 30% more than normal RTV silicones so about Â£90 for 5kg of it (ex Vat) as opposed to Â£60/70.

Dependingon the outcome of these casting trials though it really does look like it will last longer... 14 casts with our usual silicone (without mould release) would start to show up some problems/dryness.

So it looks pretty good to me so far.

Once its got a name and a final price, and pending any problems with it down the line, it looks like an absolute crackerjack silicone.

i'll keep y'all informed.

Oh its from Italy fwiw.

Sparky · Post by **Sparky** » Mon Oct 16, 2006 11:47 pm

Italy you say. . .might be a stretch for us to get it here unless they have a state side factory. Please keeps us up to date anyways.

DX-SFX · Post by **DX-SFX** » Tue Oct 17, 2006 4:09 am

Who's your supplier Antenociti?

Antenociti · Post by **Antenociti** » Tue Oct 17, 2006 5:17 am

Nick from TOMPS (www.tomps.com)