Mold Surgery

Performing surgery on a new mold. I created registration keys by cutting a zigzag into the outer edges. This helps the two parts line up more accurately for casting. I used a weitlaner retractor to hold the silicone open while I cut towards the inside, straightening out the seam as I got closer to the sculpt. It can be a bit tricky. The key is knowing where the edges of the sculpt are so that I’m not cutting totally blind. I usually take a picture of the mold set up before pouring so I have something to reference when I cut. I get better at it each time!

Pouring Silicone

Pouring the second half of a mold. ?I mix the silicone twice, transferring it into a clean cup to get a thorough mix. Not pictured, I use a vacuum chamber to pull air out of the silicone before pouring. I’ll be pressure casting later, so this step is important. Casting under pressure crushes trapped air, forcing resin into tiny details, allowing clear resin to cure bubble free. If any bubbles are left in the mold, pressure casting will cause it to deform wherever there are voids. Science magic! ?

Posted by Rachel De Urioste Art on Wednesday, December 26, 2018

Pouring the second half of a mold. I mix the silicone twice, transferring it into a clean cup to get a thorough mix. Not pictured, I use a vacuum chamber to pull air out of the silicone before pouring. I’ll be pressure casting later, so this step is important. Casting under pressure crushes trapped air, forcing resin into tiny details, allowing clear resin to cure bubble free. If any bubbles are left in the mold, pressure casting will cause it to deform wherever there are voids. Science magic!