Thermoplastic Elastomer Molding Guidelines
| Suggested Remedies Perform in numerical order by column |
Problem | ||||||||||||
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| Flash | Jetting | Knit Lines | Non-uniform Color | Over Mold Breaks Thru | Shorts | Surface Sinks | Surface Splay | Parts Sticking in Cavity | Poor Adhesion | Warp | |||
| Add Mechanical Interlocks |  |
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| Add Surface Texture | |
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| Add Pneumatic Air Poppets |  |
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| Check for Material Contamination |  |
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| Check Mold Shut-Off | |
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| Check Vent Depth | |
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| Clean Mold Surface |  |
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| Decrease Back Pressure | |||||||||||||
| Decrease Injection Pressure | |
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| Decrease Injection Speed | |
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| Decrease Hold Pressure | |
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| Decrease Material Temperature | |
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| Decrease Mold Temperature (Cavity) | |
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| Decrease Shot Size | |
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| Dry Material |  |
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| Gate in Thickness Cross Section | |
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| Imcompatible Materials | |
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| Increase Amount of Gates | |
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| Increase Back Pressure | |
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| Increase Hold Pressure | |
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| Increase Injection Pressure | |
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| Increase Injection Speed | |
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| Increase Material Temperature | |
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| Increase Mold Temperature | |
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| Increase Shot Size | |
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| Increase Substrate Support | |
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| Move Gate Location | |
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| Redesign Ejection Mechanism | |
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This information is intended to be used only as a guideline for designers and processors of modified thermoplastics for injection molding. Because injection mold design and processing is complex, a set solution will not solve all problems. Observation on a “trial and error” basis may be required to achieve desired results.
