can water based clay be molded?

[Docbudo]

I have some rebound25 platinum(silicone) but was told that I might need a tin cure?? can anyone hear shed some light??

 

[REL]

I have some rebound25 platinum(silicone) but was told that I might need a tin cure?? can anyone hear shed some light??

You can't use any clay that contains sulfur or the silicone won't cure against it. I'm not sure if water based clay will work as I think it might have sulfur in it, I use an oil based sulfur free clay for molding purposes. Any pottery/ceramic shop would have it.

 

[PetarB]

Water-based clay will inhibit RTV curing. 'Klean Klay' is a product I use which is oil based.

 

[falcondesigns]

Klean Klay is the only thing to use in moldmaking.Alexander

 

[Docbudo]

I used just regular water based clay(no Sulfur) and rebound 25 a platinum cure silicone and the mold came out just fine. Thanks to all for input.

 

[seknewb]

Water-based clay will inhibit RTV curing.

Not true. You absolutely CAN use water based clay (ie - wed/white/pottery clay) with any type of silicone (platinum or tin). The moist surface actually acts as an excellerant for the RTV. We do it every day at Stan Winston's, Rick Baker's, ADI, etc. (the LA effects shops) when making molds. I've been doing it for over 20 years there, and in fact, it's just about all we use for mold work. We almost never use Klean Klay (although it would work fine. It's just a lot more trouble to smooth out.)

It's true that sulpher can play havoc with Platinum silicone, but your standard water clay (pottery clay) doesn't have any in it. The only time a molding material might have issues curing against water clay is when you're dealing with polyester based products (ie-fiberglass resin). Even that can be avoided with a little know-how and present no issues at all.

Get that stuff out and use it. A light coat of crystal clear will make your clean-up from the silicone that much easier.

 

[PetarB]

Ah, thanks for the professional clarification. I had a problem once using a water based clay and found others shared my problem, so that's where my comment comes from.

 

[Neon Sentry]

Doesn't a shot of clear coat solve any potential problems with the clay reacting to the molding material?