Helical Insert When repairing machines, installing equipment, or servicing parts, many people have run into this problem:No matter how you tighten the screw, it won’t hold—the threaded hole is stripped. If you simply switch to a larger screw, it often affects the structure.If you re-tap the hole, it may not hold and can fail again quickly. That’s when a Helical Insert becomes a practical and widely used solution. --- 1. What Is a Helical Insert? In Simple Terms: It Rebuilds a

Metric and Imperial In hardware parts, machining, and equipment maintenance, it’s common to encounter a confusing situation: you only want to find a screw or a pin, yet the specifications appear in two completely different formats — one written as M4, M6, M8 (metric), and another as 1/4"-20 or #8-32 (imperial). Many people wonder:“Why aren’t these specifications unified?”“Since they look similar, can they substitute for each other?” The answer is: No.Metric and imperial syste

When installing C-type retaining rings (circlips / retaining rings), relying on bare hands or non-specialized tools can lead to slipping,...

Parallel Key In mechanical transmission and assembly, the parallel key is a small yet crucial component that determines whether parts operate securely. Installed between the shaft and hub (such as gears, pulleys, and couplings), it transmits torque and prevents relative sliding. If the size is chosen incorrectly or installed improperly, it can lead to loosened parts, reduced mechanical precision, or even shaft damage. --- How to Select Parallel Key Size Selection is mainly ba