Urethane Casting is most commonly used during the prototyping process, and can generally be expected to hold +/- .010″ tolerances with +/-0.003 in/in (whichever is greater). For parts with tight tolerance requirements, FATHOM generally recommends CNC machining or injection molding. Regarding soft parts, there is a Shore A tolerance of +/-10. Please note, the above tolerances are not guaranteed because geometries vary and every application is different, so please speak directly with an expert at FATHOM.

Soft Tool Casting Requires a master pattern and a silicone tool be made.
Master Patterns Usually CNC machined master patterns that last up to one year for most geometries, though masters can break during the making
of the silicone tool. 3D printed (e.g. PolyJet or SLA) masters have a shorter shelf life. Masters are destroyed after their useful life.
3D Printed Tools Tools are good for up to 20 parts for most geometries and can deliver quality parts up to 90 days from being made—tools are
destroyed after their useful life.
Overmold Complex parts such as overmolds can be achieved, however casting process does not result in a very strong chemical bond between
shots, regardless of material selection. Parts should be designed to maximize mechanical bonding between shots.
Color Parts can be casted in color and will approximately match specified Pantone color, however, paint is recommended for show models
(greater cosmetic result) and parts that require exact Pantone color matching.

Urethane Casting enables designers and engineers to get production-like material parts in their hands quickly, whether a company is in the midst of the prototyping phase of product development or needing finished looking parts for final tests and presentations.

ABS-Like 85 D Can Be Colored For Near Match To Pantone Common Material Choice Injection Molding
UL94V0 Rated 74 D UL94V0 Rated Material Meets Specified Flammability Standard
Polypropylene-Like 80 D
High Temp 80 D Light Tints Are Very Difficult As Resin Is Naturally An Off White Glass Transition (Tg) At Over 120°C
Clear High Temp 87 D Clear Only Requires A High Polish To Achieve Water Clear Finish, Glass Transition (Tg) At 110°C
Silicone 30A-50A Can Be Colored For Near Match To Pantone Cannot Paint, Food Grade Compression Molding Or Liquid Silicone Injection Molding
Increased range of shore values are possible, talk to an expert directly to learn more
Rubber-Like 30A-90A Cannot Paint Injection Molding, Compression Molding, Or Liquid Silicone Injection Molding
Clear Rubber-Like 30A-80A Clear, Can Be Tinted To Achieve Transparency Clear, Cannot Be Painted

Additional Notes // If color matching needs to be exact, FATHOM often recommends doing a first article (which will extend the timeline). If a color or assembly match needs to be made for other parts, a sample part is recommended to confirm color match. Parts can be molded in glossy, or matte finish—please always specify. If Shore A needs to be exact, FATHOM recommends a first article, as well as casting in a .25″ thick test slug for durometer measurement. This may add to the timeline.

Need A Material Not Listed? Please Speak With A FATHOM Expert Directly About Additional Material Options



Urethane Casting Brochure An Overview of Material Options & Considerations for Download Download Pdf
Urethane Casting Material Datasheets An Overview of Standard Materials for Urethane Casting—Includes Information on ABS-Like, UL94V0 Rated, Rubber-Like, High-Temp, Clear High-Temp, and PP-Like Download Pdf

From models to prototypes for short-run applications like product trials, urethane casting is a great way to fabricate a low volume of parts that accurately mimic the color, texture, feel, and other physical properties achieved if it was an injection molded part.

Talk with an expert directly to learn more about FATHOM’s urethane casting services—upload files to get started.