Before we even talk about making slip casting molds, we need to discuss something important, your prototype. This is what you will make your mold from (some people call it a model)

Why is your prototype so important? It dictates what your cast product will be. If you have marks, rough spots, or unintentional lines on your prototype, it will show up in your cast. If you don’t make your prototype right, it won’t release from the mold.

In my several years of mold making, I have learned along the way some helpful tips to making successful prototypes. So, I’ve decided to share these with you today!

#1. Use a smooth, white clay

Using a white porcelain or very smooth white stoneware clay is better than using a grog red or brown clay. The porcelain clay is easier to get perfectly smooth. If you use a grog clay, those little tiny beads of grit are hard to smooth out and can show in the plaster mold, and in your cast piece. 

Using a white clay will make...