10 Lbs ULTRACAL 30 Gypsum Cement – Plaster – for Moldmaking and Casting, Ideal for Latex Molds! Takes Excellent Detail

I used latex and silicone rubber molds of real rocks to cast plaster rocks to use on my model railroad.Over the years, I’ve used Hydrocal and variations of casting plasters.While Hydrocal sets up very strong and can create pretty good detail, I’ve found that a high grade casting plaster can capture better detail from my molds then Hydrocal.The ULTRACAL 30 Gypsum Cement – Plaster accomplishes this. The first time I casted a rock, I was amazed at how much better it captured the details than Hydrocal did. I like to mix it with cold water to a pancake-like batter consistency so I can pour into my molds. I then let it set up for a couple of hours or more until completely set up. Note: like most plasters, it will generate a bit of heat while curing. Not enough to burn you, but just be aware.When removing from my molds, the plaster is quite strong. Even thins parts are not very brittle.I am very happy with this choice. If you do a lot of casting and require excellent detail, this is the prefect choice.