Need Help Demolding

[SG Merc]

A little while back I had made a simple one piece mold of something using Smooth On's Brush-On 40. After molding it I made a mother mold out of plaster.

There was some slight resistance demolding the master, but I got it out without too much hassle. The problem comes now though, after pouring the resin (Smooth-Cast 321). While I did use a release (Ease Release 200), the casting was stuck to the mold.

Since I didn't need the mold, I took a razor to it and got most of it off. But now I'm left with patches of rubber on my casting. I need advice on cleaning it off. Would the rubber react to extreme temperatures or any chemicals? It's hanging on very tightly.

Thanks for any suggestions.

 

[hydin]

hmmmm

silicone is sort of made to not react to other stuff.

i doubt chemicals or heat would work for either. you may want to try a lubricant and a flat sharp knife/scapel blade. (never thought id use that sentence..)

best of luck on getting it fixed though. im kind of hesitant to mold up some stuff i need to mold because of this very reason.

chris

 

[Java]

Brush-On 40 is urethane rubber, not silicone rubber. It sounds like there wasn't enough mold release and the urethane rubber bonded with the urethane casting.

You could try sanding it off?

 

[SG Merc]

Javamonkey, I hadn't realized that it was a urethane. That explains it. I normally use liquid rubber, and had got this to make a quick mold--teaches me a lesson for not paying attention to that detail.

Thanks for the tips, I'll probably end up using a combination of cutting/sanding. I appreciate the advice.