Teaching The Exceptions To The Rule…

A colleague of mine were recently discussing employee training, and the conversation moved towards this question… George I understand that there are general rules that can be taught, but how do you handle the exceptions that come up from time to time? My Response There are always exceptions to the rule, but it is more important to teach your employees the fundamentals […]

Understanding Back-Flow Within the Barrel…

I received an interesting follow-up question regarding one of my earlier posts… Steve One of our techs stated that there is back-flow in the barrel. Is this true? How does this happen? My Response Yes, back flow does occur within the barrel in three ways: 1) Material will flow back over the check ring – […]

Assisting Part Ejection From Long Cores

I received this e-mail from a molder overseas… Nathan We are molding PS 750 (NL)  tubes in an eight cavity mold. When we use a higher mold temperature, part ejection is good, but the parts display sinks near the slides. With a lower temperature, we can mold parts which look good, but are difficult to eject. We […]

What is 100% Full?

I received this follow-up question regarding a previous blog entry…  Rafael If you recommend the mold is only filled 95-98% during first stage, how is 100% determined? My Response Personally, I view a 100% full part as the weight of one where the polymer just reaches the end of fill… such a part would have […]

Applications for Cashew Gates

I just recently received this question from a mold maker… KG When would you recommend the use of cashew gates? note: Cashew gates, or banana gates, are semi-circular gates which tunnel under the parting line to gate on the underside of the part. During ejection, they detach from the part and curl out of the […]