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Durable Resin vs Flexible Resin

Polymer · grade comparison

Durable Resin and Flexible Resin are both polymer grades. Durable Resin is the stronger of the two: tensile strength 28 MPa (4.06 ksi) against 9 MPa (1.29 ksi) for Flexible Resin, about 3.1 times as much. In exchange, Flexible Resin is the more ductile: elongation 120% versus 55% for Durable Resin, and Durable Resin is harder (70 Shore D vs 30 Shore D). Durable Resin is stiffer (1 GPa vs 0.01 GPa) and Flexible Resin runs hotter in service (65°C vs 40°C continuous). On the shop floor, Durable Resin machines more easily (good vs poor) and Durable Resin sits in a lower cost tier (standard, $$) than Flexible Resin (premium, $$$).

Durable ResinChoose it when strength drives the design, or when the part is machined in volume.

Flexible ResinChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Durable Resin vs Flexible Resin: properties

Durable ResinFlexible Resin

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

1 GPa0.15 Msi
0.01 GPa0 Msi

Poisson's Ratio

0.4
0.48

Tensile Strength (Ultimate)

28 MPa4.1 ksi
9 MPa1.3 ksi

Yield Strength (0.2% offset)

22 MPa3.2 ksi
—

Elongation at Break

55%
120%

Compressive Strength

40 MPa5.8 ksi
5 MPa0.65 ksi

Flexural Strength

30 MPa4.4 ksi
—

Flexural Modulus

0.7 GPa0.1 Msi
—

Izod Impact, Notched

108 J/m2 ft·lbf/in
—

Hardness, Shore D

70 Shore D
30 Shore D

Hardness, Rockwell R

85 HRR
—

Compressive Modulus

—
0.01 GPa0 Msi

Shear Strength

—
6 MPa0.87 ksi

Hardness, Shore A

—
80 Shore A

Tear Strength

—
24 kN/m137 lbf/in

Compression Set (22 h, 70 °C)

—
4%

Physical

Density and transition temperatures.

Glass Transition (Tg)

45°C113 °F
5°C41 °F

Water Absorption (24 h)

0.6%
1.2%

Water Absorption (Saturation)

1.6%
—

Refractive Index

1.51
1.5

Same in both: Density 1.12 g/cm³0.04 lb/in³

Thermal

How each material carries heat and how hot it can run.

Specific Heat Capacity

1,500 J/kg·K0.36 BTU/lb·°F
1,650 J/kg·K0.39 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

130 µm/m·K72.2 µin/in·°F
180 µm/m·K100 µin/in·°F

Max Service Temperature (continuous)

40°C104 °F
65°C149 °F

Heat Deflection Temp. @ 0.45 MPa

43°C109 °F
60°C140 °F

Heat Deflection Temp. @ 1.8 MPa

33°C91 °F
—

Limiting Oxygen Index

—
19%

Max Service Temperature (short-term)

—
85°C185 °F

Same in both: Thermal Conductivity 0.2 W/m·K0.12 BTU/hr·ft·°F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

1×10¹² Ω·m3.94×10¹⁹ µΩ·in
1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in

Dielectric Strength

16 kV/mm406 V/mil
14 kV/mm356 V/mil

Dielectric Constant (1 MHz)

3.2
4

Volume Resistivity

1×10¹⁴ Ω·cm
1×10¹³ Ω·cm

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

80 / 100
70 / 100

Same in both: UV / Weathering Resistance 25 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

55 / 100
15 / 100

Weldability

5 / 100
—

Formability (cold)

15 / 100
—

Polishability

60 / 100
25 / 100

Mold Shrinkage

—
1.5%

Processing Melt Temperature (typ.)

—
30°C86 °F

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

130 MJ/kg55,890 BTU/lb
115 MJ/kg49,441 BTU/lb

Same in both: Embodied Carbon (primary production) 5.5 kg CO₂/kg · Typical Recycled Content 0%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

25 kN·m/kg
8 kN·m/kg

Specific Stiffness (E / density)

0.9 MN·m/kg
0 MN·m/kg

Thermal Shock Resistance Index

0
1

Same in both: Thermal Diffusivity 0.1 mm²/s

Strength versus weight

Yield strength against density for every polymer grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

0.1110100123Density (g/cm³)Yield strength (MPa) — log scaleFlexible ResinDurable Resin

Manufacturing and finishing

CapabilityDurable ResinFlexible Resin
Default conditionStandardShore A 80
Relative cost$$ Standard$$$ Premium
Min. machined wall——
Best machined surface——

Both are offered for Injection molding and 3D printing. Both take the same 12 finishes: Chrome Plating (Plastic), Conductive Coating, Dyeing (Nylon), EMI Shielding Coating, Painting, Primer Coating, Soft Touch Coating, Spray Painting, Tinted Coating, UV Coating, Vacuum Metallization, Waterproof Coating.

Durable Resin vs Flexible Resin — frequently asked

Is Durable Resin stronger than Flexible Resin?

Yes. Durable Resin has a typical tensile strength of 28 MPa (4.06 ksi) against 9 MPa (1.29 ksi) for Flexible Resin — about 3.1 times as much.

Which is cheaper, Durable Resin or Flexible Resin?

Durable Resin is the lower-cost material: it sits in the standard tier ($$) while Flexible Resin is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, Durable Resin or Flexible Resin?

Durable Resin. Its machinability rates good (55/100) against poor (15/100) for Flexible Resin.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Durable Resin and Flexible Resin side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.