RTV (Room-Temperature Vulcanizing) Molding:
RTV Molding is the process of making soft rubber tools with silicone rubber.
The process starts with a master model, usually created on one of our rapid prototyping machines. Once the master part is finished and detailed, we cast liquid silicone in a form to create a mold. The mold can be complex with multiple parts and parting lines, slides, threaded inserts, and over molding; or very simple, with one piece cast in an open mold.
Several factors influence the approach we take to guarantee the best results. These include:
- Desired surface finish: gloss, satin, matte, textured, etc.
- Part geometry: are there undercuts or pulls on the part?
- Durability: how many parts are required from the mold?
Standard lead time for RTV molds is three days. However on very simple parts, two days is possible. We guarantee our molds for 25 casts when using rigid urethane; soft elastomeric urethanes extend the life of the mold.
The greatest benefit of RTV molding and urethane casting is accuracy. Every visible feature of the master part will be replicated in the resulting cast. The process does involve some shrink which must be taken into account when high dimensional tolerances are required.
