Urethane Rubber Mold for Plaster or Concrete CastingApril 17, 2017Our 75 Shore A Urethane Rubber is a pourable material great for making molds that stand up well to repeated castings of cement, concrete, Hydrocal, plaster and other gritty and/or abrasive materials. It is a 1:1 by volume mix ratio, so no scale is needed. For this project, I will be making a one piece […]
