How tools actually work, and how to choose one
Find Tool Editorial Team 
An oscillating multi-tool is best at short, precise cuts in tight spaces where a full-size saw or grinder can’t reach or can’t be controlled safely — flush trims against a wall, plunge cuts into a panel, scraping old adhesive, or sanding a corner. It swaps blades and heads fast but isn’t built for long, heavy-duty … Read more
A rotary tool is a small handheld motor that spins a narrow shaft at high speed, holding interchangeable bits in a collet or chuck. It is genuinely good at detail work — engraving, fine grinding, deburring, small cuts and polishing — and genuinely bad at removing large amounts of material fast. It is a precision … Read more
An SDS chuck is a spring-loaded, keyless bit holder that grips a bit by its grooved shank instead of clamping it tight like a normal drill chuck. It lets the bit slide back and forth a few millimetres inside the chuck while still turning with it, which is exactly what a rotary hammer’s internal piston … Read more
A surface plate is a very flat, very stable slab — usually granite or cast iron — used as a reference surface for precision measuring, marking out and checking whether a workpiece is actually flat. It doesn’t cut or shape anything; it’s a known-good baseline that everything else is measured against. What does a surface … Read more
Parallax error is the shift in an apparent reading that happens when your eye isn’t lined up directly with the scale and the mark or needle you’re reading. Look at a ruler from an angle instead of straight on, and the line you “see” against a mark isn’t the line that’s actually there. The measurement … Read more
Calibration means comparing a measuring tool against a known, trusted reference and finding out how far it disagrees, then adjusting it or noting the error. Most home-workshop tools do not need a fixed schedule — they need a quick accuracy check before a job that matters, after a drop or knock, or whenever a reading … Read more
A torque screwdriver is a screwdriver built to stop transmitting force once a chosen twisting effort has been reached, so the screw is tightened consistently rather than as hard as an arm can manage. It’s needed anywhere over-tightening can crack a part, strip a thread, crush a gasket, or shear a small fastener — small … Read more
A plumb bob is a pointed weight hung on a string that uses gravity to find a perfectly vertical line. It has no batteries, no electronics and nothing to calibrate. Plenty of tradespeople and hobbyists still use one, mostly as a quick, reliable check when a laser or spirit level can’t be trusted or can’t … Read more
A laser distance measure is a handheld device that fires a laser dot at a target and calculates distance from how long the light takes to return, or from the phase shift in the returning beam. It replaces a tape for many jobs but struggles with reflective, transparent, dark or angled surfaces, and with strong … Read more
A bore gauge measures the internal diameter of a hole, cylinder or bushing more accurately than a caliper can manage. It solves the problem of measuring a round internal surface where jaws can’t sit square, telling you the true diameter, taper or out-of-round condition of the hole. What exactly is a bore gauge? A bore … Read more
About what you read here. Everything on Find Tool is general information and our own editorial opinion. We research carefully and we say when the evidence is unclear, but we can be wrong, things change, and no article can know your particular situation. Please do your own research and make your own judgement rather than treating anything here as the final word. Prices, products and specifications around tools and workshop equipment change constantly, and what suits one person will not suit another. Check current details yourself, and where a decision involves real money, safety or something you cannot undo, it is worth confirming with the manufacturer, or a qualified electrician or tradesperson before you act.