Ok, not really. But, my new sculpture sure looks like an alien in this photo. Or a lava lamp gone wild. Or a batch of “magic rocks”. Or?
So what are we really doing? We’re making a “waste mold” of a nearly completed sculpture. This one in fact — Peppy Poco ChaCha (say that three times fast; go on, it’s fun!)
The mold Barry is working on now is an intermediary step in the overall process of creating and producing a new sculpture. We’re only pulling one or two castings from this mold to get a hard-bodied master for me to work with. Thus it’s referred to as a “waste” mold. However, this is by no means a waste of time or effort!
You’ve no doubt noticed that the sculpture has no mane and tail… yet. I decided that in order to avoid damaging the soft clay body I would wait to add the mane and tail to a hard resin casting from the waste mold. There are a few other details to add, and I like to see how the piece “reads” in white resin before committing to a production mold.
Going through the exercise of making, cutting apart and then casting into a waste mold gives Barry a better feel for the piece overall and that will make designing the production mold go much more quickly for him, since ChaCha’s idiosyncrasies will already be dancing through Barry’s subroutine so to speak.
Here are a few pictures of the waste mold as it’s being built up layer by layer. Yes, it would be quicker to make a dump mold, but that would require a lot more silicone rubber. Pricey stuff, that silicone rubber….
Ok wait, first let me show you a diagram of the two different methods, then we’ll get back to pictures.
top: a multi-layered “brush-up” mold
bottom: a “dump” mold in which the sculpture is suspended in a container then mold material is poured (dumped) in around it.
Shown below is the first layer of a brush-up mold.
The pink and the blue are all the same silicone rubber (Smooth-On Mold Max 30), with different dyes added to each batch to keep track of the layers .
Then another pink layer and it’s time to work right side up again.
This top view gives you an idea of the all the layers that were added while ChaCha was upside down.
Now it’s time to add more silicone goo to the topside. There is method to this madness. The first few coats are drizzled on with a very runny mix of silicone, so that the rubber can ooze its way into every nook and cranny of the sculpture, capturing all the fine detail.
Later layers have had a thickener added to the silicone in addition to the dye, which makes for a more-putty like consistency that builds up thickness more quickly.
After a couple of thick coast right side up, ChaCha gets flipped over again for more layers.
Now the mold is ready to have plaster applied to the outside to create a hard “mother mold” to support the rubber. See the little purple bumps with “t-pins” stuck in them? (Indicated by the red arrows) Those will be registration locks for the plaster mother mold.
Barry will let all this set up at least over night, then apply the plaster. At that point the only photo I’d have to offer is of a white blob. That’s none too exciting, so we’ll wait to catch up with this project when Barry starts to cut all this apart.
Would you like to learn how to do this in a hands-on workshop with Barry?
He’s seriously thinking about holding a workshop next year, so your input is really important. Consider this before you respond though, you’ll need to bring your own ready-to-mold sculpture, and it will take at least three days, (probably really four or five days!) to cover the material and make a mold. And the going rate for any professional quality workshop these days is about $100 per day. So, with those factors in mind, what do you think?
Please leave a comment to let us know! Thanks 🙂
I still like the alien look…