Chain gauge

Updated 2026-08-24 · Read this page as Markdown

The thickness of the drive link tang that rides inside the guide bar groove, given in inches. The common gauges are .043", .050", .058" and .063", and the chain gauge must match the bar exactly.

Gauge is the specification buyers most often get wrong, because a chain of the wrong gauge may appear to fit: too thin and it rattles and wanders in the groove, cutting crooked and wearing the rails; too thick and it will not seat at all. Thinner gauges are lighter and used on smaller saws, heavier gauges resist the loads of large professional machines. The bar almost always has pitch and gauge stamped near the mounting slot, and reading it there is far more reliable than measuring. Quote gauge together with Chain pitch and the Drive links count when ordering.

Related terms

Chain Pitch The distance between any three consecutive rivets on the saw chain divided by two, expressed in inches. It is the dimension that must match the drive sprocket and the bar nose, and the common sizes are 1/4", .325", 3/8" (including 3/8" low profile) and .404". Chain Speed The linear speed at which the chain travels around the guide bar, in metres per second, normally quoted at maximum engine speed. It is determined by engine rpm, the number of teeth on the drive sprocket and the chain pitch. Drive links The toothed links on the underside of the chain that engage the drive sprocket and run in the bar groove. Their count is what determines the chain's overall length for a given bar. Maximum Bar Length The longest guide bar, in centimetres, that the manufacturer approves for the saw. Fitting anything longer overloads the engine and clutch and usually voids the warranty. Raker (depth gauge) The small rounded projection immediately ahead of each cutter on the chain, which limits how deep that cutter can bite into the wood. The height difference between the raker and the cutter's top plate sets the chip thickness. Recommended Bar Length The guide bar length, in centimetres, that the manufacturer considers the best match for the saw's power. It is the length the machine is normally supplied with and the one that gives the best balance of cutting reach and cutting speed.

Chain gauge

Related terms

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