Fasteners & Closures
This section names the parts that hold things together and the parts that keep them shut — screws, bolts, nuts, clips, lids, pins, anchors, and every small connector that does its job out of sight. Each entry explains what a fastener or closure is called, what role it plays in an assembly, and how to tell common designs apart. You will find entries on why some screws have an unthreaded shank, how a wall anchor grips plaster, what a split pin actually does, and why tape-measure hooks are deliberately loose. The goal is practical: when you pick up a part at the hardware store, you can name it, explain its purpose, and know which variant fits the job.
Entries
How a Ratchet Mechanism Works Inside a Socket Wrench
A ratchet uses an asymmetrical gear and a spring-loaded pawl to allow motion in one direction while blocking it in the other. Inside a socket wrench, this lets you tighten a bolt without lifting the tool off between turns.
Why a Combination Wrench Has Two Different Ends
A combination wrench carries an open-end jaw on one side and a closed box-end ring on the other, and both ends are angled at 15 degrees to the handle — a design that gives you two distinct ways to turn the same fastener.
What the Notch in a Cable Tie Is For
The small notch or hook on a cable tie head is not decorative — it lets you hang the tie from a hole before tightening, or lock two ties together for longer bundles.
The Difference Between a Keyway and a Scratch
A keyway is a precisely machined slot that locks a gear or pulley to a shaft; a scratch is accidental surface damage that looks superficially similar but serves no function.
What Is a Split Pin?
A split pin is a cheap, disposable fastener with two tines that you bend apart after insertion to lock a nut, bolt, or clevis pin in place.
Why Some Screws Have an Unthreaded Shank
The smooth section under a screw head is not an accident. It lets the head pull two parts together, keeps the fastener cool while driving, and carries shear loads.