Author Archives: WorkingBear


Jan09
Why Do Electronic Component Leads Turn Yellow, Purple, or Blue After Reflow? Causes and Solutions

Workingbear recently received questions from readers about electronic component soldering leads turning yellow or showing discoloration (purple, blue, etc.) after going through the reflow oven. Why do the leads of components discolor after reflow? Does this discoloration affect product functionality? … Continue reading

Jan02
How to Monitor the Quality of Incoming Plastic Resin?

This is a answer to a question from a community member asking about plastic quality control. The question was: “Can we rely solely on MI (Melt Index) values to monitor the quality of plastic resins? And does an increase in … Continue reading

Dec26
The Relationship Between MFI and Re-grind/Recycle Resin in Plastics

When discussing whether using re-grind resin in plastics leads to degradation, Workingbear sought advice from industry experts. Most professionals agreed that it does cause degradation. However, opinions on whether MFI values can reliably indicate the presence of re-grind resin are … Continue reading

Dec19
7 Ways to Identify if a Plastic Factory is Using Re-grind Resin

It’s an open secret in the plastic injection molding industry that re-grind resin is often added during injection. Some manufacturers even claim that, given the current competitive environment and cost-cutting pressures, it’s impossible to make a profit without using some … Continue reading

Dec12
Why Re-grind Resin in Plastic Injection Molding Causes Degradation and Weakens Strength

The use of re-grind resin and recycled material in plastic injection molding is a persistent challenge for engineers. The more re-grind resin or recycled material is added, the more severe the degradation of the plastic becomes. This degradation weakens the … Continue reading