1. Den of Angels is closing in August 2026. New account registrations are closed. Please see this thread in Den of Angels news for important information: /threads/the-future-of-den-of-angels.893314/
    Dismiss Notice

Casting My 2-piece molds are bonding - mold release problem?

Apr 17, 2011

Watch Thread
    1. Have pity on me, for I'm a newb at this.

      I think I'm having a problem with my mold release (or my application of it). I'm using Alumilite silicone for my molds, and Castin' Craft mold release (in a spray bottle) from the craft store.

      Everything is fine with the first side of the mold, but when I try to make the second, it consistently bonds to the first. I've tried three times; first I thought I didn't use enough mold release, so I followed the instructions on the bottle to the letter the second time, but had the same result. The third time I applied the release with a brush instead, but still ended up with a solid square of silicone.

      I think I'm either using poor mold release or making a really obvious error that I just can't see. :sweat

      Please help me.
       
      #1 We Are Seven, Apr 17, 2011
      Tools
      + Quote Reply
    2. I'd say you got a bad batch of mold release, or it might be the brand. But it doesn't sound like you are doing anything wrong!
       
      #2 Renzi, Apr 17, 2011
      Tools
      + Quote Reply
    3. Are you able to cut the molds apart afterwards to salvage them? I would say use some vaseline (generous coat) on the first layer of silicone to prevent it sticking to the second. It has happened to me too, but I can usually tear the silicone because the bond between layers is only partial, otherwise I cut the rest.

      Maybe the mold release is not suitable for the application, what does the Alumilite supplier recommend?
       
      #3 twigling, Apr 17, 2011
      Tools
      + Quote Reply
    4. Thank you both for your responses. Alumilite recommends their own mold release, which I probably should have bought in the first place. Since it doesn't seem that the problem lies with the silicone, I think I'll just get their brand of mold release and see if that doesn't work.
       
      #4 We Are Seven, Apr 17, 2011
      Tools
      + Quote Reply
    5. I use Alumilite silicon...Castin' Craft DOES NOT WORK on Alumilite Silicon....so it's not a bad batch


      I use Vaseline with great success :)
       
      #5 SheJackal, Apr 17, 2011
      Tools
      + Quote Reply
    6. Yay! I finally have a working two-piece mold. :XD
      Thank you!
       
      #6 We Are Seven, Apr 19, 2011
      Tools
      + Quote Reply
    7. #7 Mr. Orange, Apr 19, 2011
      Tools
      + Quote Reply
Draft saved Draft deleted
Toggle Width
Styler
Styler
Color Options
Color Options