RTV Molding & Urethane Casting

Manufacture Low- to Medium-Volume Plastic Parts with Production-Level Quality.

Urethane casting spans the low-volume step between prototypes and production.

Injection molds can be complex to design and very expensive to produce. Depending on complexity, producing injection molds take weeks and even months. RTV molding can be an ideal alternative solution for producing production quality parts, from the very small to very large, and from the very simple to very complex.

RTV molding is a rapid tooling process for creating production-quality parts with rubber molds. RTV molds can be a much faster and much less expensive to build, as compared to metal injection molds. Production runs that do not justify the cost of hard tooling can often be economically manufactured with RTV molds.

The RTV molding process uses liquid urethane plastics that closely mimic the properties of injection-molded plastics. Parts can be made in a very wide range of properties, from very rigid to very flexible, with a full range of custom colors that can be blended to match your specifications. 

Depending on part geometry, InterPRO’s tooling team can build the RTV mold and start producing high-quality prototype or production parts in under one week.

How it Works

To produce RTV molds for the urethane casting process, a highly accurate master pattern is made with rapid prototyping or CNC. The desired surface texture is applied to the pattern by the finishing team. The texture will be exactly replicated in the production cast parts.

The RTV tool maker builds a box around the master pattern. After gates, sprues, and parting lines are added to the pattern, liquid silicone rubber is poured around the pattern. After the mold is allowed to cure overnight it is cut open and the master pattern is removed. The mold is then ready to be filled with urethane, silicone, or another custom-blended material. Custom colors will be cast-in, exactly matching the customer specifications.

The urethane material is cast (injected) into the mold under pressure or vacuum and allowed to cure. Cast parts perfectly match the original pattern when they are removed from the mold.  

The cast urethane process offers an extremely wide range of material, color, and texture options. Urethane cast parts can also be clear, color-matched, painted (including EMI shielding), have installed inserts, and custom-finished.

“Just an FYI, the parts you sent over look great.

I’m very pleased with them. Thank your guys that worked on it for me.”

“Thanks so much for all of your efforts.

We look forward to working with you in the future.”

“Our client was very impressed.

You’ll probably start getting business directly from them in the future. Nice job. It’s a pleasure working with you guys.”

“Top-notch stuff!

Thanks for hitting the lead time on the head, too.”

RTV Molding and Urethane Casting Uses, Benefits & Applications

  • Very low tooling cost
  • Very fast delivery of first production parts
  • Highly flexible parts
  • Ease of making changes
  • Economical for low-volume production
  • Allows part performance testing using different durometers
  • Bridge-tooling for production before injection molds are built
  • Highly complex parts
  • Extremely tiny parts
  • Overmolded features with different materials and colors
  • Multiple durometers in one part
  • High chemical resistance
  • High abrasion resistance
  • Full spectrum of colors and textures
  • Cast in colors
  • Composite parts with metal and other fillers
  • Overmolded and captured parts

RTV Molding and Urethane Casting Gallery (click to enlarge)

Low-Volume, High-Quality Parts are a Quick Quote Away.

Request yours today and get it within 2 hours.

Medical Patient Cart


Cast Urethane Case Study: The Titan Medical Patient Cart

When Ximedica was asked by Titan Medical to design and deliver three complete engineering verification units of their SPORT™ Surgical System patient cart, they contacted InterPRO.

630 Industrial Park Road
Deep River, CT 06417

E-mail InterPRO Additive

Toll Free: 888-392-0957
Local: 860-526-5869

630 Industrial Park Road
Deep River, CT 06417

E-mail InterPRO Additive

Toll Free: 888-392-0957
Local: 860-526-5869