Injection Molding Trouble shooting guide

The purpose of this guide is to identify a broad range of molding problems that can arise in injection molded parts. 

This is intended as a guide only and may not be the optimum solution for every application.

When troubleshooting, it is important to remember that the first step is to identify the true issue.

When making processing changes, make one change at a time and allow two cycles, at a minimum, before moving on. 

If the change made does not fix the problem, then you should put that setting back to it's original setting before making next change.

short Shot

short shot.jpg

Blisters / Bubbles

Blister Bubbles.jpg



Cracking / Crazing

Cracking Crazing.jpg

Black Specks

Black Specks.jpg

Sinks and Voids

Sinks and Voids.jpg



Flow Lines

Flow Lines.jpg



Dimensional Inconsistency

Dimensional Inconsistency.jpg



Excessive Cycle Time

Excessive Cycle Time.jpg

Burns in gate area

Burns in gate area.jpg

Burns at the end of fill

Burns at the end of fill.jpg



Nozzle Drooling

Nozzle Drooling.jpg

Parts sticking in mold

Parts sticking in mold.jpg

Splay(Silver Streaking)

Splay Silver Streaking.jpg

Sprue Sticking

Sprue Sticking.jpg

Surface Imperfections

Surface Imperfections.jpg

Weak Weld Lines

Weak Weld Lines.jpg

To the best of our knowledge the information contained in this document is accurate, however, we do not assume any liability whatsoever for 

the accuracy or completeness of such information.  

Since we have no control over the use to which others may put our product, we cannot guarantee that results the same as those described 

in this document will be obtained.  The Buyer assumes sole responsibility for results obtained in reliance upon this publication.  

We recommend that persons intending to rely on any recommendation or to use any equipment, processing technique or material mentioned

 in this publication should satisfy themselves as to such suitability and that they can meet all applicable safety and health standards.

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