High Strength 2 is a tin-based silicone mold making rubber with high tear strength and is great for making all types of molds – it’s soft enough for 1-piece molds with undercuts and strong enough for 2-piece molds with secure alignment.
Prior to using product, please read all Technical Data, Safety Data, and Instruction sheets linked below.
We use this High Strength 2 for molding 3D printed parts, so we can cast in resin. The high tear strength is great and you can typically use this for stuff that would typically require a 2 piece mold.
I have been making RTV molds since 1972. Recently I have been using HS2 to make multi piece molds of small (10mm) model buildings. I use a triple beam balance to weigh the base and catalyst. I mix a small quantity and brush it over the mold so there won't be any bubbles on the surface of the model, then pour a thin stream and blow on the rubber to burst any bubbles as I pour the rest of the mold. I pour 20 to 50 grams at a time. The last lot of RTV set up so fast that the working time was reduced to no more than 7 minutes after mixing, making it hard to remove the bubbles or even pour the rubber.