OVERMOLDED PROTOTYPES
Create models that look like they just came off the production line.
Overmolded Prototypes
Overmolding is a process in which a softer layer of material is bonded over a harder substrate or structural component of a part. It can be used to improve functionality or to change the look or feel of a part.
Overmolding can deliver a wide range of product benefits such as:
- Textures that make handheld items easier to hold and use.
- Vibration and noise reduction.
- Greater electrical resistance.
- Increase shock absorbency.
- Enhanced aesthetics
- Improved ergonomics
Common Overmolding Applications
Overmolded prototypes are used in a variety of industries. Examples are:
- Metal screwdriver overmolded with a plastic handle to prevent electrical shock.
- Plastic cell phone case overmolded with an elastomeric shell to increase grip.
- Metal medical device overmolded with a plastic handle to increase safety.
- Automotive connector with an overmolded gasket.
- Sporting goods utilize overmolding for enhanced durability, comfort, and show absorption.
Overmolded Part Design Considerations
- The wall thickness of the substrate and over-mold should be as uniform as possible.
- Keeping 0.5 MM minimum in corners reduces localized stresses.
- Avoid deep or un-ventable blind pockets or ribs.
- Transitions between wall thicknesses should be gradual to reduce flow problems.
- The elastomeric over-molding section should be less thick than the substrate to prevent warpage, especially critical for long, flat geometries.
- Design in a mechanical interlock when possible.
Overmolded Prototype Specification Guidelines
Outlined below are the options which need to be specified when ordering an overmolded prototype. This includes overmold material, substrate material, finish and options.
Standard Material Selection:
Custom material requests welcomed.
Specification Writers: These values are a guide and not intended for use in preparing specifications.
Urethane 30-RF-20, Shore 20A
Base Color: Off-White
Shore A Hardness: 20A ASTM-2240
Tensile Strength: 200 psi ASTM D-412
100% Modulus: 27 psi ASTM D-412
Elongation at Break: 1,000% ASTM D-412
Die C Tear Strength: 60 pli ASTM D-624
Urethane 30-RF-30, Shore 30A
Base Color: Off-White
Shore A Hardness: 30A ASTM-2240
Tensile Strength: 450 psi ASTM D-412
100% Modulus: 67 psi ASTM D-412
Elongation at Break: 1,000% ASTM D-412
Die C Tear Strength: 82 pli ASTM D-624
Urethane 30-RF-40, Shore 40A
Base Color: Off-White
Shore A Hardness: 40A ASTM-2240
Tensile Strength: 490 psi ASTM D-412
100% Modulus: 73 psi ASTM D-412
Elongation at Break: 1,000% ASTM D-412
Die C Tear Strength: 85 pli ASTM D-624
Urethane 30-RF-50, Shore 50A
Base Color: Off-White
Shore A Hardness: 50A ASTM-2240
Tensile Strength: 580 psi ASTM D-412
100% Modulus: 152 psi ASTM D-412
Elongation at Break: 435% ASTM D-412
Die C Tear Strength: 120 pli ASTM D-624
Urethane 30-RF-60, Shore 60A
Base Color: Off-White
Shore A Hardness: 60A ASTM-2240
Tensile Strength: 782 psi ASTM D-412
100% Modulus: 256 psi ASTM D-412
Elongation at Break: 581% ASTM D-412
Die C Tear Strength: 132 pli ASTM D-624
Urethane 10-4281-70, Shore 70A
Base Color: Clear Amber
Shore A Hardness: 70A ± 5 ASTM D2240-04e1
Tensile Strength: 2,200 psi ASTM D412-98a(2002)e1
Tensile Modulus: 800 psi ASTM D412-98a(2002)e1
Elongation: 860% ASTM D412-98a(2002)e1
Tear Strength: 300 pli ASTM D624-00e1
Dielectric Constant, 1 MHz: 5.84 ASTM-D150-87
Dissipation Factor, 1 MHz: 0.068 ASTM D-150-87
Urethane 10-4291-80, Shore 80A
Base Color: Clear Amber
Shore A Hardness: 80A ± 5 ASTM D2240-04e1
Tensile Strength : 2,800 psi ASTM D412-98a(2002)e1
Tensile Modulus: 1,300 psi ASTM D412-98a(2002)e1
Elongation: 720% ASTM D412-98a(2002)e1
Tear Strength: 350 pli ASTM D624-00e1
Dielectric Constant, 1 MHz: 5.55 ASTM-D150-87
Dissipation Factor, 1 MHz: 0.0614 ASTM D150-87
Urethane 30-CD-30, Clear, Shore 30A
Base Color: Clear
Shore A Hardness: 30A ASTM D-2240
Tensile Strength: 725 psi ASTM D-412
Elongation at Break: 675% ASTM D-412
Die C Tear Strength: 54 pli ASTM D-624
Electrical Properties:
Volume Resistance : >7.646E+13 ohm ASTM D-150-98
Volume Resistivity: >6.014E+15 Ohm cm ASTM D-150-98
Dielectric Constant k’@100 Hz: 6.62 ASTM D-150-98
Dissipation Factor @100 Hz: 0.103 ASTM D-150-98
Dielectric Strength (V/mil): 474 ASTM D-147-97a
Index of Refraction: 1.48822 at 20ºC, 1.48649 at 25ºC
Urethane 30-CF-50, Clear, Shore 50A
Base Color: Clear
Shore A Hardness: 50A ASTM D-2240
Tensile Strength: 250 psi ASTM D-412
Elongation at Break: 500% ASTM D-412
Die C Tear Strength: 25 pli ASTM D-624
Electrical Properties:
Volume Resistance : >7.646E+13 ohm ASTM D-150-98
Volume Resistivity: >6.014E+15 Ohm cm ASTM D-150-98
Dielectric Constant k’@100 Hz: 6.62 ASTM D-150-98
Dissipation Factor @100 Hz: 0.103 ASTM D-150-98
Dielectric Strength (V/mil): 474 ASTM D-147-97a
Index of Refraction: 1.48822 at 20ºC, 1.48649 at 25ºC
Silicone 30-DS-10, Shore 10A, Flame Rate to UL-94 HB
Base Color: Translucent
Shore A Hardness: 10A ASTM D-2240
Tensile Strength: 475 psi ASTM D-412
100% Modulus: 22 psi ASTM D-412
Elongation at Break: 1,000% ASTM D-412
Die B Tear Strength: 102 pli ASTM D-624
Dielectric Strength: >350 volts/mil ASTM D-149
Service Temperature Range: -65ºF to +450ºF (-53ºC to +232ºC)
Silicone 30-DS-15, Shore 15A
Base Color: Translucent
Shore A Hardness: 15A ASTM D-2240
Tensile Strength: 537 psi ASTM D-412
100% Modulus: 40 psi ASTM D-412
Elongation at Break: 771 % ASTM D-412
Die B Tear Strength: 112 pli ASTM D-624
Dielectric Strength: >350 volts/mil ASTM D-149
Service Temperature Range: -65ºF to +450ºF (-53ºC to +232ºC)
Silicone 30-DS-20, Shore 20A
Base Color: Translucent
Shore A Hardness: 20A ASTM D-2240
Tensile Strength: 550 psi ASTM D-412
100% Modulus: 49 psi ASTM D-412
Elongation at Break: 620% ASTM D-412
Die B Tear Strength: 120 pli ASTM D-624
Dielectric Strength: >350 volts/mil ASTM D-149
Service Temperature Range: -65ºF to +450ºF (-53ºC to +232ºC)
Silicone 30-DS-30, Shore 30A
Base Color: Translucent
Shore A Hardness: 30A ASTM D-2240
Tensile Strength: 500 psi ASTM D-412
100% Modulus: 86 psi ASTM D-412
Elongation at Break: 364% ASTM D-412
Die B Tear Strength: 108 pli ASTM D-624
Dielectric Strength: >350 volts/mil ASTM D-149
Service Temperature Range: -65ºF to +450ºF (-53ºC to +232ºC)
Silicone 15-SG-43, Shore 43A
Transparent encapsulant with good flame resistance.
Suitable for LED lighting encapsulation, power supplies, connectors, sensors, industrial controls, transformers, amplifiers, and relays.
Shore A Hardness: 43A
Thermal conductivity: 0.15 btu/hr ft ºF (0.27 W/m ºK)
Dielectric Strength: 500 volts/mil ( 19 kV/mm)
Volume Resistivity: 2.9E+14 ohm*cm
Dissipation Factor at 100 Hz: 0.00257
Dissipation Factor at 100 kHz: 0.00133
Dielectric Constant at 100 Hz: 2.72
Dielectric Constant at 100 kHz: 2.68
Linear CTE (by DMA): 340 ppm/ºC
Tensile Strength: 980 PSI (6.7 MPa, 69 Kg/cm²)
Refractive Index @ 589 nm: 1.4118
Refractive Index @ 632.8 nm: 1.4225
Refractive Index @ 1321 nm: 1.4028
Refractive Index @ 1554 nm: 1.3997
UL RTI Rating: 150ºC
Urethane 30-T32, ABS-Like, Shore 75D
Base Color: White
Shore D Hardness: 75D ASTM D-2240
Ultimate Tensile: 5,500 psi ASTM D-638
Tensile Modulus: 270,000 psi ASTM D-638
Elongation @ Break: 7.5% ASTM D-638
Flexural Strength: 7,100 psi ASTM D-790
Flexural Modulus: 250,000 psi ASTM D-790
Compressive Strength: 7,100 psi ASTM D-695
Compressive Modulus: 78,500 psi ASTM D-695
Heat Deflection Temp: 144º F / 62º C ASTM D-648
Urethane 30-T9, Heat Resistant, Shore 80D
Base Color: Off-White
Shore D Hardness: 80D ASTM D-2240
Ultimate Tensile: 5,840 psi ASTM D-638
Tensile Modulus: 246,000 psi ASTM D-638
Elongation @ Break: 4% ASTM D-638
Flexural Strength: 8,280 psi ASTM D-790
Flexural Modulus: 271,000 psi ASTM D-790
Compressive Strength: 8,760 psi ASTM D-695
Compressive Modulus: 77,400 psi ASTM D-695
Heat Deflection Temp: 194º F / 90º C ASTM D-648
Urethane 20-2522, Water Clear, Shore 80D
Color: Water Clear
Shore D Hardness: 80D
Elongation: 7%
Heat Deflection Temp: 138ºF
Tensile Strength: 6,083 psi
Elastic Modulus: 133,956 psi
Flexural Modulus: 250,992 psi
Flexural Strength, 5% Strain: 8,478 psi
Basic Finish
If SLA, layer lines ARE NOT removed. If Machined, as machined.
Standard Finish
If SLA, layer lines ARE removed - leaving a matte finish. If machined, tool markings ARE removed - leaving a matte finish. Layer lines may be present on internal or difficult to reach features.
Custom Finish Examples
Gloss finish
Textured Finish
EMI/RFI shielding
color matching
decorating
metal inserts.
Custom finish requests welcomed
Master Pattern Finishing Options
Overmolded Prototype Quote Submission
You will receive an e-mail confirming receipt of your request.
Files up to 20MB may be sent via e-mail to: Sales@Versadyne.net