The most frequently asked questions I get from this blog are from folks who are interested in making their own toys out of silicone. Someday I hope to put together a more step-by-step guide which will cover the entire casting process, but at least for now I can tell you about the materials that I’ve used when making my own toys.
Before I get started, let me remind you that I am not a medical doctor. Please use common sense when selecting materials and designing toys. I’m presenting you with the best information that I have, but using a condom over any homemade toy is the safest course of action.
The focus of this particular post is on materials, not the casting and moldmaking process itself. If you haven’t done much casting or moldmaking, I suggest you take a look at this Instructable to get you started.
The silicone I use for my toys is a brand called Smooth-On. According to the folks at Reynolds Advanced Materials, where I purchase my casting supplies, any of the Smooth-On platinum cure silicones are body safe: http://www.smooth-on.com/Silicone-Rubber-an/c2_1115/index.html
I’ve used both Dragon Skin (20 is what The Hammer is made of; 10 is softer, 30 is harder). I’ve also used Sorta-Clear 18, for the TARDIS Tickler — but unless you have a way to degas the silicone, it will be so full of bubbles you won’t be able to tell that it’s really clear.
I use LEGOs for building custom-sized mold containers, which I learned about from this article on making cock-sicles. It works really well — the LEGOs fit tightly enough together that the silicone doesn’t leak out.
For the filler material, I have used homemade Play-Doh using this recipe: http://www.instructables.com/id/How-to-Make-Playdough-Play-doh/. The downside is that it’s hard to get a nice part line, but the stuff is super cheap and easy to work with. You can also use clay as your filler material — but if the clay is going to be touching any silicone, make sure the clay is sulfur-free. Otherwise, the sulfur in the clay will prevent the silicone from curing.
I’ve also used alginate as a filler material — it’s more expensive than Play-Doh, but it gives you a really nice part line.
Update (8/14/14): I still don’t have a really good solution to what to make your mold out of that’s cheaper than more silicone. I tried making a mold out of plaster, but it was really fragile and took a long time to try. I also tried using Oogoo to make a mold instead (see http://www.instructables.
You’ll also need to use mold release — Since I’m pouring silicone into a silicone mold, I use Ease Release.
If you have other questions about materials, don’t hesitate to post them in the Comments section below!