In the field of mold machining, the term ‘burr’ is frequently encountered. Although minute in size, this phenomenon has a significant impact on product quality, functionality and safety, and must not be taken lightly. In this article, we will explain in detail what a ‘burr’ is in the context of mold machining, its causes, the issues it presents, and methods for preventing and removing it. ◆ What is a burr? A ‘burr’ refers to the minute protrusions or raised edges that form on the machined...

Understanding the Ductility and Failure Mechanisms of Resins through ‘Molecular Motion’ When designing injection-molded parts or selecting materials, ‘This material is prone to cracking’ ‘This resin is sticky’ ‘It has whitened on impact’ ‘It withstood deformation but fractured’ one may encounter phenomena such as these. Even though they are all ‘plastics’, why do some materials stretch significantly, while others are hard and brittle, some bend easily, and others break immediately? The answer...

1. The Basic Concept of the Safety Factor In product design, the **safety factor (SF)** is a ‘margin of safety’ established to prepare for unforeseen loads and uncertainties when a structure or component is actually in use. Put simply, it acts as ‘insurance against failure’ and reduces the risk of accidents or breakdowns by ensuring a margin between the design strength and the actual operating conditions. For example, if a force of 100 N is expected to be applied to a component, and the...