Design Guides
In-depth design guides full of best
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Design Guide : Urethane Casting
Overview
Urethane Casting provides end-use, rigid or flexible plastic parts with production-level quality. Built without expensive and time-consuming hard tooling, our urethane casting process uses a 3D printed master pattern and silicone molds to deliver high-quality, short-run parts up to 30” long.
The finished dimensions of urethane cast parts depends on the accuracy of the master model, part geometry and casting material. In general, a shrinkage rate of +0.15% is expected.
The finished dimensions of urethane cast parts depends on the accuracy of the master model, part geometry and casting material. In general, a shrinkage rate of +0.15% is expected.
Typical Build Process
STEP 1: First a master pattern is printed in either PolyJet 3D (PJ3D) or Stereolithography (SLA) to provide an accurate silicone mold. Sometimes tape is placed on flat surfaces to allow for crisp, clean removal of the cast part during post-processing.
STEP 2: Next, the master pattern is encased in liquid silicone to form an accurate mold.
STEP 3: After the mold cures it is cut into distinct halves and the pattern is removed. This cavity is used for casting the end product. Note that features that may fatigue, such as through holes, are replaced with dowels.
STEP 4: Once the mold tool is created our production team will use urethane and other resins to fill the voids. The material will cure and be removed from the tool. This process repeats until the project is finished!
