Reference Tables
Density of Plastic, Shrinkage, Draft Angle, SPI Mold Class & Conversion Reference Charts
Plastic Shrinkage Values | |
Material | Shrink in/in |
ABS High Impact | 0.005 – 0.007 |
ABS Heat Resistant | 0.004 – 0.005 |
ABS Medium Impact | 0.005 |
Acetal | 0.020 – 0.035 |
Acrylic General Purpose | 0.002 – 0.009 |
Acrylic Heat Resistant | 0.003 – 0.010 |
Acrylic High Impact | 0.004 – 0.008 |
Ethylene Vinyl Acetate | 0.010 – 0.030 |
Ionomer | 0.003 – 0.020 |
Nylon 6/6 | 0.010 – 0.025 |
Nylon 6/6 | 0.007 – 0.015 |
Nylon 6/10 | 0.010 – 0.025 |
Nylon 11 | 0.010 – 0.025 |
Nylon 12 | 0.008 – 0.020 |
Nylon Glass Filled | 0.005 – 0.010 |
Polybutylene | 0.020 (molded) |
Polybutylene | 0.040 (aged) |
Polycarbonate | 0.005 – 0.007 |
PET (Amorphous, petg, pctg) | 0.003 – 0.005 |
Polyester .025 – .050 THICK | 0.006 – 0.012 |
Polyester .050 – .100 THICK | 0.012 – 0.017 |
Polyster .100 – .180 THICK | 0.016 – 0.022 |
Polyester PBT | 0.010 – 0.020 |
Polyester PET 30% GF | 0.001 – 0.002 |
Polyester PBT 30% GF | 0.003 – 0.005 |
POLYETHERIMIDE | 0.005 – 0.007 |
Polyethylene Low Density | 0.015 – 0.035 |
Polyethylene High Density | 0.015 – 0.030 |
PPO/Styrene CO (NORYL) | 0.005 – 0.007 |
Polypropylene | 0.010 – 0.030 |
PPO/Styrene G.P. | 0.002 – 0.008 |
PPO/Styrene Heat Resistant | 0.002 – 0.008 |
PPO/Styrene Impact Mod | 0.003 – 0.006 |
Polysulfone | 0.008 |
Polyurethane | 0.010 – 0.020 |
PVC Rigid | 0.002 – 0.004 |
PVC Semi-Rigid | 0.005 – 0.025 |
PVC Flexible | 0.015 – 0.030 |
SAN | 0.002 – 0.006 |
Density of Plastic Values – Selected Resins | ||
Material |
70°F DENSITY
gr/cc |
MELT DENSITY
gr/cc |
ABS (Injection Grade) | 1.05 | 0.97 |
ABS 30% GR | 1.28 | |
Acetal | 1.42 | 1.17 |
Acetal 20% GF | 1.55 | |
Acrylic General Purpose) | 1.16 | 1.04 |
Cellulose Acetate | 1.26 | 1.13 |
Cellulose Butyrate | 1.20 | 1.07 |
Cellulose Propionate | 1.22 | 1.10 |
Ethylene Vinyl Acetate | 0.95 | |
Ionomer | 0.95 | 0.73 |
Nylon 6/6 | 1.14 | 0.97 |
Nylon 6 | 1.13 | 0.97 |
Nylon 6/10 | 1.08 | 0.97 |
Nylon 6/12 | 1.07 | 0.97 |
Nylon 11 | 1.04 | 0.97 |
Nylon 12 | 1.02 | 0.97 |
Nylon 30% GF | 1.36 | |
Polybutylene | 0.92 | |
Polycarb/Ester Alloy | 1.20 | |
Polycarbonate | 1.20 | 1.02 |
Polycarbonate 30% GF | 1.42 | |
Co-Polyester PETG | 1.27 | 1.12 |
Co-Polyester PCTG | 1.24 | 1.08 |
Polyester PBT | 1.34 | 1.11 |
Polyester PBT/PET 30% GF | 1.58 | |
Polyester PET (Bottle) | 1.40 | 1.20 |
Polytherimide | 1.27 | |
Polyethylene Low Density | 0.92 | 0.76 |
Polyethylene Medium Density | 0.92-0.94 | 0.74 |
Polyethylene High Density | 0.94-0.97 | 0.72 |
Polythyl 30% GF HDPE | 1.18 | |
PPO/Styrene (NORYL) | 1.07 | 0.90 |
PolyphenYlene Sulfide | 1.35-1.80 | |
Polyphen Sulfide 40% GF | 1.65 | |
Polypropylene | 0.90 | 0.70 |
Polypropylene 30% GF | 1.13 | |
POLYStyrene GP | 1.05 | 0.97 |
POLYStyrene Impact Mod | 1.04 | 0.96 |
Polysulfone | 1.25 | 1.16 |
Polyurethane | 1.20 | 1.13 |
PVC – Rigid | 1.39 | 1.30 |
PVC – Pipe | 1.44 | 1.32 |
PVC – Flexible | 1.29 | 1.20 |
SAN | 1.08 | 1.00 |
T/P Ruber (Santoprene) | 1.08 | 1.00 |
T/P Elastomer (Urethane) | 0.97 | 0.93 |
0.83 | 0.82 |
Common Plastic Abbreviations
Common Abbreviations for Misc Resins | |
Resin Generic Name | Common ABBR |
Acrylonitrile-Butadiene-Styrene | ABS |
Cellulose Acetate | CA |
Cellulose Acetate Butyrate | CAB |
Cellulose Acetate Propionate | CAP |
Chlorinated Polyethylene | CPE |
Chlorinated Polyvinyl Chloride | CPVC |
Ethylene-Propylene Diene Rubber | EPDM |
Expandable Polystyrene | EPS |
Ethylene Vinyl Acetate | EVA |
Fiber Reinforced Plastic | FRP |
High Density Polyethylene | HDPE |
High Impact Polystyrene | HIPS |
Low Density Polyethylene | LDPE |
Linear Low Density Polyethylene | LLDPE |
Maleic Anhydride | MA |
Medium Density Polyethylene | MDPE |
Polyamide (Nylon) | PA |
Polyacrylonitrile | PAN |
Polybutylene | PB |
Polybutylene Terephalicate | PBT |
Polycarbonate | PC |
Polyethylene | PE |
Polyetheretherketone | PEEK |
Polyetherimide | PEI |
Polyetherketone | PEK |
Polyethylene Terephalicate | PET |
Polyethylene Terephalic Clycol | PETG |
Polyimide | PI |
Polymethyl Methacrylate | PMMA |
Polyoxymethylene | POM |
Polypropylene | PP |
Chlorinated Polypropylene | PPC |
Polyphenylene Oxide | PPO |
Polyphenylene Sulfide | PPS |
Polyphenylene Sulfone | PPSU |
Polystyrene | PS |
Polysulfone | PSU |
Polyurethane | PU |
Polyurethane | PUR |
Polyvinyl Chloride | PVC |
Reinforce Polybutylene Terephthalateic | RPBT |
Reinfor Polyethylene Terephalic | RPET |
Reaction Injection Molding | RIM |
Styrene Acrylonitrile | SAN |
Styrene Butadiene Rubber | SBR |
Styrene Maleic Anhydride | SMA |
Sheet Molding Compound | SMC |
Thermoplastic Elastomer | TPE |
How much draft angle do you need in your plastic part?
Below are draft angles commonly used from 1/32″ to 1″ are noted in degrees in the table below.
Each block is the amount of draft with the corresponding angle and depth of the cavity.
Inches to Millimeters Conversion Chart
Inch Fraction | Inch Decimal | mm | mm | Inch Decimal | |
1/32 | 0.03125 | 0.794 | 1 | 0.0394 | |
1/16 | 0.0625 | 1.588 | 2 | 0.0787 | |
3/32 | 0.09375 | 2.381 | 3 | 0.1181 | |
1/8 | 0.125 | 3.175 | 4 | 0.1575 | |
5/32 | 0.15625 | 3.969 | 5 | 0.1969 | |
3/16 | 0.1875 | 4.763 | 6 | 0.2362 | |
7/32 | 0.21875 | 5.556 | 7 | 0.2756 | |
1/4 | 0.25 | 6.350 | 8 | 0.3150 | |
9/32 | 0.28125 | 7.144 | 9 | 0.3543 | |
5/16 | 0.3125 | 7.938 | 10 | 0.3937 | |
11/32 | 0.34375 | 8.731 | 11 | 0.4331 | |
3/8 | 0.375 | 9.525 | 12 | 0.4724 | |
13/32 | 0.40625 | 10.319 | 13 | 0.5118 | |
7/16 | 0.4375 | 11.113 | 14 | 0.5512 | |
15/32 | 0.46875 | 11.906 | 15 | 0.5906 | |
1/2 | 0.5 | 12.700 | 16 | 0.6299 | |
17/32 | 0.53125 | 13.494 | 17 | 0.6693 | |
9/16 | 0.5625 | 14.288 | 18 | 0.7087 | |
19/32 | 0.59375 | 15.081 | 19 | 0.7480 | |
5/8 | 0.625 | 15.875 | 20 | 0.7874 | |
21/32 | 0.65625 | 16.669 | 21 | 0.8268 | |
11/16 | 0.6875 | 17.463 | 22 | 0.8661 | |
23/32 | 0.71875 | 18.256 | 23 | 0.9055 | |
3/4 | 0.75 | 19.050 | 24 | 0.9449 | |
25/32 | 0.78125 | 19.844 | 25 | 0.9843 | |
13/16 | 0.8125 | 20.638 | 26 | 1.0236 | |
27/32 | 0.84375 | 21.431 | 27 | 1.0630 | |
7/8 | 0.875 | 22.225 | 28 | 1.1024 | |
29/32 | 0.90625 | 23.019 | 29 | 1.1417 | |
15/16 | 0.9375 | 23.813 | 30 | 1.1811 | |
31/32 | 0.96875 | 24.606 | 31 | 1.2205 | |
1 | 1 | 25.400 | 32 | 1.2598 |
We kindly ask you to make use of our reference tables and fill out the forms provided. Our reference tables are designed to assist you in finding the information you need quickly and easily, and our forms are created to ensure we have all the necessary details to process your requests accurately and efficiently. By using our reference tables and filling out the forms, you help us to provide you with the best possible service and ensure that your requests are dealt with promptly. So, please take advantage of these resources and help us to serve you better. Stelray proudly serves nationwide customers in our Connecticut Injection Molding facility.