Gauge
Gauge turns up in 3 fields: railroad, textiles, shop slang. Here is what it means to the people in each one.
Gauge in railroad
The distance between the inside faces of the two rails, 4 feet 8.5 inches on standard-gauge track.
Gauge is measured 5/8 inch below the top of the rail, between the faces that the wheel flanges ride against. Standard gauge in North America is 4 feet 8.5 inches, and track that spreads wider can let a wheel drop in between the rails, one of the most common causes of derailment. Federal track standards set the maximum wide gauge for each class of track, and inspectors check it with a gauge bar.
"Gauge is running 57 and a half through the curve, the ties aren't holding spikes anymore, get a slow order out."
Gauge in textiles
The number of stitches and rows that fit into a standard measurement of knitted or crocheted fabric.
The measure of stitch density in knitting or crochet, typically expressed as the number of stitches and rows per four inches (or ten centimeters). It determines the final physical size of a garment. Makers must knit a test swatch and adjust their needle size to match the pattern's specified gauge, otherwise the finished piece will not fit.
"My stitch gauge is spot on, but my row gauge is a little tight so the sweater might end up short."
Gauge in shop slang
A measurement system for the thickness of sheet metal or the diameter of wire.
A standardized number indicating the thickness of sheet metal or the diameter of electrical wire. The scale runs in reverse to physical size, meaning a smaller number represents a thicker, heavier material. Mechanics and fabricators rely on these numbers to select the correct material for structural integrity or electrical load capacity.
"We need a piece of 16 gauge to patch that floor pan, the 22 gauge is just going to burn through when you weld it."