Hello, We need to start by saying that in no way are we pastry chefs, however we feel like we can add to this topic because we have been making molds for many years. We are cake decorators who were frustrated by the high cost of silicone molds so we decided to challenge ourselves by making our own over three years ago. Here are a number of things we have learned that may help. 1. If you are going to use the molds for any type of food contact the silicone must be platinum cured. Platinum is a precious metal which creates a very pure, clean, odorless, food safe silicone. 2. Liquid platinum cured RTV (room temperature vulcanizing or silicone that can cure at room tempurature) is a wonderful product but here are a few drawbacks for a pastry chef working in a kitchen. This product usually needs to be degassed before pouring. When you mix the silicone with the catalyst (usually 10/1 ratio) air pockets form so when you pour two things can happen, you will see bubbles throughout your mold, when the bubbles start to break during curing, your mold can become distorted, rendering it useless or the bubbles remain without bursting still rendering it useless. You need a vacuum chamber to pour the silicone in and degass it then pour the mold. There are a few tricks that may help so you can avoid degassing. One is to mix the silicone then use a channel ( a paper towel holder, cut in half and wrapped in plastic wrap works ) to pour the silicone down in a long thin stream to avoid bubbles. The second is to mix the silicone then place it in the freezer for a while until it degasses naturally, then pour the mold. The freezer method doesn't work with all silicones though. Platinum silicones are addition cured which means that the more heat the faster the cure so by putting it into the freezer your slowing the cure time. I would suggest trying this with a small amount of silicone first. 3. Never use a master made from clay unless it is kleen klay specifically made for the molding process. Most clay's will interfere with platinum silicones ability to cure. Plaster, permastone or resin work very well as masters. If you are designing your own piece make it from clay then you can make a temporary mold by using insta mold and make a master by pouring plaster into the temporary mold. 4. Platinum silicone putty that you mix by hand works very well for small flat molds, we have over 500 on our website right now. You can bake in them , no problem! We have made mini cakes in them, they work wonderfully. The only thing you need to remember is to lower the oven temperature by five or ten degrees because silicone holds the heat so well, and watch them closely because cooking time is usually much faster. We are in the process of making larger molds right now as well as 3D molds that you can pour into for baking or molding chocolate pieces etc... We placed keys into the molds so you can fit them together perfectly and stand them up with a metal band (or rubber band if you aren't baking in them)to hold them together. We plan on trying one out in the next week or so. We will let you know how well it works. Sorry this ended up so long but we wanted to try and help as much as possible. Please feel free to mail us if you have any questions, or post them and we will help if we can. Thanks and good luck! Adrienne & Teri First Impressions Molds
