This difference is important to know for your resin success! Depending on what you want to make, choosing the right resin for your project is important so that you can get the results you want.
Let’s start with a couple basic concepts
A doming resin mixes thick enough that when you use it, it finishes in a smooth dome on your project. If you think about it like a teardrop, when you drop doming resin onto a surface, it will stay in a domed shape. A doming resin is what you want to use when you want a curved surface to something or if you want to use resin on a surface where there are no sides to keep the resin contained. The surface tension of doming resin will be enough for it to want to stay on the surface. Note: The larger the surface, the harder it is to keep resin on that surface, even if it is a doming resin.
A casting resin mixes in a thinner viscosity. It is meant to be used in something with sides like molds. This thinner viscosity is what makes casting resins ideal for spreading into all the intricate parts of a mold. You could also use a casting resin a bezel, but is is not going to have a domed finish. Casting resins also do not self-level like doming resins do. This means that casting resins will not necessarily level themselves out over a surface.