Review on 🌱 Mold Star 15 Silicone Rubber for Slow Moldmaking - Trial Unit by Gelin Battle

I have tried many mold silicones from several brands and so far that this is my favorite for several reasons.1. Long pot life means there is enough time to mix and pour before everything starts to thicken. If you start making your own molds like I did, you'll find dozens of ways to mix things up. Good longevity means you have plenty of time to fix it if (or in my case, WHEN) something goes wrong. Silicone is not cheap, so mistakes can be expensive - leeway is good! 2. Relatively quick curing time, especially considering how much time you have before the mix starts to set. I can come home from work, fill out the form and it's ready to go, giving me time before I have to go to bed.3. A platinum treatment is always a plus. For some mysterious reason I've had problems with tin silicone and the material I usually cast (epoxy). I think post-curing the tin-hardening molds should solve part of the problem, but even when I tried this, the tin-hardening molds left a slightly sticky, sticky film on the surface of my castings. I've had good luck with platinum silicones, which actually *improve* the curing of my epoxy.4. The low viscosity means you won't get bubbles until you stir, and the trapped air in the detailed shapes won't be forced through the super-thick, gooey mess to dislodge. This means that, in contrast to many other silicones, excellent results can be achieved with this silicone even without vacuum degassing. One last plus/minus: this material is soft, but not insanely soft. The flexibility makes it ideal for complex parts as you don't need Herculean hands to pull the casting out of the mold. However, a really soft, flexible silicone like this can also cause some problems. So, here are a few tips I learned the hard way :).1. If you're casting something in layers, make sure you either place your mold in some sort of support tray (a mug or plastic bowl will do), or make your mold with extra "cushioning" rubber at the base and sides . Why? Well, if you move the mold around too much, these amazing natural properties of silicone can work against you and knock your layer out, meaning the next layer can flow down the sides. Having something to ensure the soft shape doesn't get pushed around makes a world of difference.2. If you're making a mold with a lot of cavities, it's probably best to plan it so everything can be demolded at once. The flexibility means it's fairly easy to accidentally knock out one casting while trying to remove another. All in all, this is a truly amazing product. Highly recommended!