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Plastic Injection Molding Tolerance Guide

All plastics will expand and contract to a certain extent under the influence of heat and moisture. Therefore, we work closely with all customers to optimize their designs and avoid any defects as much as possible. Unless otherwise stated, we comply with DIN 16742 standard tolerances for plastic injection molding.

The below latest Tolerance Guide are suitable for our usual plastic Injection parts, with Commercial Tolerance and Precision Higher Cost.

Commercial Tolerance					Precision Higher Cost
Dimension	1 to 20 (+/-mm)	21 to 100 (+/-mm)	101 to 160 (+/-mm)	For each 20mm over 160 add	1 to 20 (+/-mm)	21 to 100 (+/-mm)	over 100
ABS	0.100	0.150	0.325	0.080	0.050	0.100
ABS/PC Blend	0.100	0.150	0.325	0.080	0.050	0.100
GPS	0.075	0.150	0.305	0.100	0.050	0.080
HDPE	0.125	0.170	0.375	0.100	0.075	0.110
LDPE	0.125	0.170	0.375	0.100	0.075	0.110
Mod PPO/PPE	0.100	0.150	0.325	0.080	0.050	0.100
PA	0.075	0.160	0.310	0.080	0.030	0.130
PA 30% GF	0.060	0.120	0.240	0.080	0.030	0.100
PBT 30% GF	0.060	0.120	0.240	0.080	0.030	0.100
PC	0.060	0.120	0.240	0.080	0.030	0.100
PC 20% Glass	0.050	0.100	0.200	0.080	0.030	0.080
PMMA	0.075	0.120	0.250	0.080	0.050	0.070
POM	0.075	0.160	0.310	0.080	0.030	0.130
PP	0.125	0.170	0.375	0.100	0.075	0.110
PP 20% Talc	0.125	0.170	0.375	0.100	0.075	0.110
PPS 30% GF	0.060	0.120	0.240	0.080	0.030	0.100
SAN	0.100	0.150	0.325	0.080	0.050	0.100

*Project review required for all materials.

Straightness/ Flatness Tolerances

Warpage is due to the difference between the mold shrinkage rates in the direction of the mold flow and across the flow. The effect is more noticeable in fiber filled plastics. The major factor is different wall thickness as a thick section normally shrinks more than a thinner section. Mold design, gate position and process control can minimize this effect, however, the material behavior cannot be corrected 100%. Therefore a practical tolerance must be negotiated with the respective production units.

Commercial Tolerance			Precision Higher Cost
Dimension	0 to 100 (+/-mm)	101 to 160 (+/-mm)	0 to 100 (+/-mm)	101 to 160 (+/-mm)
ABS	0.380	0.800	0.250	0.500
ABS/PC Blend	0.380	0.800	0.250	0.500
Acetal	0.300	0.500	0.150	0.250
Acrylic	0.180	0.330	0.100	0.100
GPS	0.250	0.380	0.180	0.250
Mod PPO/PPE	0.380	0.800	0.250	0.500
PA	0.300	0.500	0.150	0.250
PA 30% GF	0.150	0.200	0.080	0.100
PBT 30% GF	0.150	0.200	0.080	0.100
PC	0.150	0.200	0.080	0.100
Polycarbonate PC 20% Glass	0.130	0.180	0.080	0.100
Polyethylene	0.850	1.500	0.500	0.850
Polypropylene	0.850	1.500	0.500	0.850
Polypropylene, 20% Talc	0.850	1.500	0.500	0.850
PPS 30% GF	0.150	0.200	0.080	0.100
SAN	0.380	0.800	0.250	0.500

Hole Diameter Tolerances±mm

Commercial Tolerance					Precision Higher Cost
Dimension	0-3 (+/-mm)	3.1-6 (+/-mm)	6.1-14 (+/-mm)	14-40 (+/-mm)	0-3 (+/-mm)	3.1-6 (+/-mm)	6.1-14 (+/-mm)	14-40 (+/-mm)
ABS	0.050	0.050	0.080	0.100	0.030	0.030	0.050	0.050
ABS/PC	0.050	0.050	0.080	0.100	0.030	0.030	0.050	0.050
GPS	0.050	0.050	0.050	0.090	0.030	0.030	0.040	0.050
HDPE	0.050	0.080	0.100	0.150	0.030	0.050	0.050	0.080
LDPE	0.050	0.080	0.100	0.150	0.030	0.050	0.050	0.080
PA	0.050	0.080	0.080	0.130	0.030	0.040	0.050	0.080
PA 30% GF	0.050	0.050	0.080	0.080	0.030	0.040	0.050	0.050
PBT 30% GF	0.050	0.050	0.080	0.080	0.030	0.040	0.050	0.050
PC	0.050	0.050	0.080	0.080	0.030	0.040	0.050	0.050
PC 20% GF	0.050	0.050	0.080	0.080	0.030	0.040	0.050	0.050
PMMA	0.080	0.080	0.100	0.130	0.030	0.050	0.050	0.080
POM	0.050	0.080	0.080	0.130	0.030	0.040	0.050	0.080
PP	0.050	0.080	0.100	0.150	0.030	0.050	0.050	0.080
PP 20% Talc	0.050	0.080	0.100	0.150	0.030	0.050	0.050	0.080
PPS 30% GLASS	0.050	0.050	0.080	0.080	0.030	0.040	0.050	0.050
SAN	0.050	0.050	0.080	0.100	0.030	0.030	0.050	0.050