Category Archives

In response to a recent class, a participant encountered this result… Participant We have very fast screw recovery times, typically less than 2 seconds. When performing the rear zone temperature study, there was a steady increase in recovery time from 1.78 sec. @ 225°C to a result of 1.82 sec. at 260°C. Does this seem like a […]

I occasionally see employees confuse blisters and delamination and wanted to clarify this here. Delamination Delamination is the layering of the polymer as it fills and packs the mold. With this defect, different unconnected layers of plastic develop and form within the part.  Blisters Blisters are gas bubbles which appear as small bumps on the surface of […]

This question highlights the complexity of polymers…  Saeed I came across a troubleshooting guide for oversized parts and one of the remedies was to increase the mould temperature. Now I understand it will help shrink the part to the required size, but one thing I do not understand that due to higher mould temperature, melt […]

This question came in as a follow-up to a recent post. SA Recently we were processing Acetal material with black masterbatch. During the whole run the screw recovery time kept going up excessively before coming back to normal values after a few minutes. This was repeated throughout the run and it happens on this particular […]

A recent blog reader send me a question last week… Reader We have recently come across multiple part issues relating to end of arm tooling damaging the part.  We’ve found that a few of our {brand removed} machines have a lot more platen drift than our other machines. We tried setting our mold open tolerances tighter […]