Issues with Dragon Skin silicone and casting..PLEASE HELP!

[Mystique]

Why in the hell is my Smooth-On Dragon Skin silicone coming out so sticky when I pull it out of the Oomo mold? When I use the Smooth Sill 920 it works just fine.. I just cant afford the 920 right now :-(

First, I sprayed on some ease release 200 and let it dry. Then I applied my gold Cast Magic color powder.. mixed the dragon skin and colored it with black using Silc Pig. I pulled it out the oomo mold 10 hours after casting and it's very stick or tacky to the touch.. Why, why, why?

I know I mixed it properly as the "bottom" surface was fully cured and not tacky.. the only part that's tacky is the part that came in direct contact with te oomo.

There has to be a reason and a work around.. Any suggestions or advice would be greatly appreciated.

 

[mrbungle]

you can powder it down with babypowder to get rid of the stickness if you are not planning on painting the piece.


also there might be a compatiblity problem with the silicones. platinum based silicone will not cure right in tin based silicone molds or not cure at all.

 

[robn1]

...there might be a compatiblity problem with the silicones. platinum based silicone will not cure right in tin based silicone molds or not cure at all.

Yep, Smooth-on's technical bulletin on Dragon Skin mentions this. Oomoo is tin cure and may inhibit platinum cure silicones. You may have to remake your mold from platinum cure silicone.

 

[Mystique]

Damit!! ok.. going to pick up some smooth sill and re sculpt the dam thing.. UGH!!

Thanks, guys

 

[robn1]

What is your pattern sculpted from? It's probably fine, you just need a new mold, something other than Oomoo.

 

[Mystique]

I used Chevant soft clay.. and it no longer exist.. the sculpt was destroyed after the de-mold process.. but it's all good.. it wasn't that hard to sculpt. I'll do so tonight and get the smooth sil 920 on Monday

 

[mrbungle]

you can cast it is in resin then remold it.

anytime i sculpt something in clay ,the first thing i do when the mold is done is make a resin casting of the sculpt. that way if i ruin the mold i atleast have a back up copy to mold.

 

[robn1]

Excellent idea :thumbsup