Defect Troubleshooter
Search 48 common molding defects and compare a quick fix with the professional optimized fix.
48 defects
| Defect | Quick Fix | Professional Fix |
|---|---|---|
| Shrinkage | Increase injection pressure | Increase packing pressure + extend packing time |
| Flash | Increase gate | Reduce gate size OR increase clamp tonnage |
| Bubbles | Ensure material fully dried | Ensure material fully dried + increase back pressure |
| Weld Lines | Increase & optimize hot runner | Increase melt temp + optimize gate location or hot runner nozzle |
| Warpage | Balance mold temperature | Improve cooling uniformity + balance cavity filling |
| Flow Marks | Reduce cooling time | Increase melt temp + optimize gate design |
| Silver Streaks | Clean mold release agent | Dry material thoroughly + reduce melt temp (degradation) |
| Short Shot | Reduce recycled material | Increase shot size + melt temp + injection speed (reduce regrind %) |
| Burn Marks | Lower molding surface temperature | Reduce injection speed + improve venting depth |
| Color Difference | Control mold temperature | Control melt + mold temps uniformly |
| Dimensional Deviation | Stabilize packing stroke | Control packing pressure profile + cooling uniformity |
| Surface Scratches | Polish mold surface + adjust shot size | Polish mold surface to SPI finish + verify ejection system |
| Ejector Whitening | Slow ejection speed | Slow ejection speed + increase draft angle |
| Jetting Marks | Use fan gate | Use fan gate OR modify gate location/geometry |
| Delamination | Dry material fully | Dry material fully + check melt temp (no degradation) |
| Cold Slug Marks | Insulate hot runner | Optimize hot runner tip temp + adjust decompression |
| Black Spots | Clean screw carbon buildup | Clean screw/barrel + reduce melt temp + check regrind |
| Deformation | Extend cooling time | Extend cooling time + improve cooling channel layout |
| Sticking | Apply mold release | Increase draft angle + polish cavity + apply release agent |
| Brittle Cracking | Reduce recycled material | Reduce regrind ratio + ensure proper drying + lower melt temp |
| Overflow / Flash | Repair parting surface | Repair parting surface + increase clamp force + check vent depth |
| Ripple Marks | Control mold temperature gradient | Control mold temp uniformity + optimize gate design |
| Dents | Increase packing stroke | Increase packing pressure + extend packing time |
| Short Shot | Increase shot size | Increase shot size + check non-return valve + raise melt temp |
| Too Many Bubbles | Clear vent grooves | Clear vent grooves + increase back pressure + dry resin |
| Uneven Color | Increase mixing time | Increase screw back pressure + ensure proper colorant dispersion |
| Poor Gloss | Hard chrome plate mold surface | Polish cavity to high SPI finish + control mold temp |
| Difficult Demolding | Increase draft angle | Increase draft angle (1-3° min) + polish surface |
| Mold Deposits | Clean carbon buildup regularly | Clean mold regularly + reduce melt temp + improve venting |
| Drooling | Adjust suck-back amount | Adjust screw decompression (suck-back) + reduce nozzle temp |
| Gate Sticking | Lower material temperature | Lower melt temp OR increase gate taper/draft angle |
| Heat Deformation | Improve post-cooling | Extend in-mold cooling time + use fixture post-cooling |
| Stress Cracking | Apply annealing treatment | Apply annealing + reduce packing pressure + lower melt temp |
| Shrinkage Variation | Control packing in stages | Multi-stage packing pressure profile + optimize gate location |
| Melt Fracture | Reduce shear rate | Increase gate size + reduce injection speed |
| Brittle Parts | Ensure sufficient drying | Ensure proper drying + reduce regrind + lower melt temp |
| Part Sticking | Extend cooling time | Extend cooling + increase draft angle + polish cavity |
| Fast Discoloration | Reduce screw speed | Reduce screw speed + lower melt temp + reduce back pressure |
| Light Part Weight | Increase metering stroke | Increase shot size stroke + check non-return valve |
| Low Strength | Increase glass fiber content | Add GF + ensure fiber orientation + check drying |
| Mixed Impurities | Use finer filter screen | Use finer screen pack + clean regrind source |
| Strong Odor | Apply vacuum drying | Apply vacuum/desiccant drying + reduce melt temp |
| Excessive Burrs | Repair mold clearance | Repair mold clearance + increase clamp tonnage |
| Dense Pores | Increase back pressure | Increase back pressure + reduce screw RPM + dry resin |
| Cold Slug Marks | Control hot tip temperature | Control hot tip temp + adjust suck-back + optimize cycle |
| Deep Shrinkage Voids | Adjust gate location | Adjust gate location + increase packing pressure/time |
| Obvious Delamination | Check material compatibility | Check material compatibility + dry thoroughly + check melt temp |
| Silver Streaks | Remove barrel moisture | Dry material properly + reduce melt temp + check screw condition |