Find Tool Editorial Team

A thread pitch gauge is a small hand tool with a fan of thin, notched metal leaves used to identify the thread pattern on a screw, bolt or nut. Each leaf has teeth cut to a specific pitch; whichever leaf meshes cleanly with the threads tells you what pitch you’re dealing with, without guessing or … Read more

A depth gauge measures how deep a hole, recess, groove or step is, rather than how wide or long it is. A flat base sits on the surface of the workpiece while a thin rod or blade slides down inside the feature until it touches bottom, and the amount the rod has moved gives the … Read more

A machinist’s square is a precision measuring tool made to a tight, verifiable tolerance for checking true 90-degree angles on metal, machine setups and fine woodworking joints. A try square is a woodworker’s layout tool, built to mark and check squareness on timber, but not made or guaranteed to the same standard of accuracy. Both … Read more

A straight edge is a rigid bar or blade — usually steel, sometimes granite or aluminium — with at least one edge machined to be as close to perfectly straight as the maker can manage. It is used to check whether a surface is flat, whether a line is true, and as a fence to … Read more

A feeler gauge is a set of thin, precisely made metal blades, each one a different thickness, used to measure or check a small gap between two surfaces. You slide the blade into the gap; if it fits with a slight drag, the gap matches that blade’s marked thickness. It’s a low-tech, highly reliable way … Read more

A dial indicator measures very small amounts of movement — typically a few thousandths of an inch or a few hundredths of a millimetre — and displays that movement on a dial with a sweeping needle. It is used to check that something is straight, flat, round, level, or moving exactly as far as it … Read more

A micrometer measures a dimension to a finer resolution than a caliper can reliably show, and it does so using a calibrated screw thread that applies a consistent, repeatable measuring force every time. A caliper’s sliding jaw depends on how hard the operator squeezes it — a micrometer’s ratchet stop removes that variable. That difference … Read more

A vernier caliper is a hand measuring tool with a fixed main scale and a sliding secondary scale that lets you read a length far more finely than the main scale’s markings alone. It measures outside width, inside width, depth and step height, and it needs no battery. It looks intimidating the first time you … Read more

Accuracy is how close a reading is to the true value. Precision is how consistent repeated readings are with each other, whether or not they’re correct. Resolution is the smallest change a tool can display or detect. A tool can have fine resolution and still be inaccurate, and it can be precise while being consistently … Read more