Now that you’ve made a mold of the stone hands (and if you’re having issues getting the stone out of the fiberglass mold, because we did, then we ended up having to chisel it out, and shatter and break the stone out of the hand) you can finally cast some arms with fingers that come out. If you’ve forgotten, the reason we need these for gloves is so that when we take the glove off of the arm after we’ve cast it in foam latex, the glove won’t tear with you taking it off, since the fingers will come off and you can then take the fingers out. If you used a stone hand to bake these in, then you have a very real possibility (I almost want to say 100%, but there may be someone out there who got lucky) that the fingers will snap when you take the glove off, or even sooner, when you make the fiberglass mold of the glove sculpture.
The resin we used to cast the hands in is a two part casting resin, we used Instacast from Douglas and Sturgess. We also used square brass tube, you need two sizes, one to go inside the other, we just picked the two that looked to be small enough to fit inside a pinky without touching the sides, and 1/2 inch steel tube, enough to stick several inches down the arm and also have enough sticking up to grab on to.
Start with the thumb, take masking tape and support the tube that will be sticking out of the thumb, where it would be going into the hand. Once the tube is masked inside, release the mold with fiberglass mold release, bolt the mold together, turn it on it’s edge, and level it so that when you pour resin into it, it will fill up only the thumb cavity, but also have a nice straight edge that will be easy to take off of the rest of the hand, as you can see in our thumb images.
Take out the thumb, and repeat the process for the pinkie and ring finger, they will both share one of the square tubes. Don’t forget the mold release!
Now, put mold release on the mold, thumb and fingers, and outside the square tubes sticking out. Now put the larger square tubes over the smaller ones, put the thumb and other fingers into the mold, and assemble the mold.
Prop the mold up vertically, and level the top of the mold so it will be even.
Mix the batch of the two part resin, we needed to use two containers because we didn’t have one that was large enough to hold everything we needed, and pour the resin into the mold.
Make sure to hold the steel rod in the end of it so that it will be easier to get out of the mold later!
Now DON’T just pour this mold and go do whatever. You need to stand by, as soon as the resin is cured just enough that it’s solid, but maybe still a little sticky and flexible, then take it out of the mold. If you wait any longer, until it’s fully cured, then it’s going to be impossible to take the thumb and other fingers out of the mold since we’re casting hard objects in a hard mold. You can clean off the excess resin with an exacto blade.
There you go, now you have your very own hand with fingers that come out that you can use to sculpt on, and make foam latex gloves out of!