We have had fabricators from all over the world tell us that there is nothing quite like Rebound® 25 brushable silicone rubber. It is so easy to use, versatile for handling different jobs and stands up to production casting of just about anything including chemically harsh resins.
After months of field testing, we are pleased to announce Rebound® 40 which is a Shore 40A durometer brush-on rubber. Compared to the Rebound® 25, the 40A is a bit stiffer and preferred by some artisans for applications like making rotational casting molds. It is mixed 1A:1B by volume and holds a vertical surface extremely well. A few drops of Thi-Vex® thickener will add thixotropy to the rubber for filling in undercuts.
Rebound® 40 and 25 are compatible and work well together. For example, some fabricators will apply 2 layers of Rebound® 25 followed by 2 layers of Rebound® 40. The stiffer Rebound® 40 will seat positively in the shell and resist falling when the mold is placed upside down during casting.