Feeler Gauges — Lutherie Encyclopedia

Feeler GaugesType: toolA set of thin metal blades in graduated thicknesses for measuring small gaps in guitar setup and construction.## Description Feeler gauges are a set of thin, flat metal blades of precisely known thicknesses, typically ranging from 0.05mm (0.002 inches) to 1.0mm (0.040 inches). The blades are held together on a pivot like a pocketknife. Each blade is stamped or etched with its thickness. They are made from hardened spring steel with smooth, polished surfaces. Standard automotive feeler gauge sets work well for lutherie. ## Use in Lutherie Feeler gauges are used to quantify small gaps that cannot be measured with a caliper or ruler. Common applications include measuring neck relief (the gap between the fret top and a straightedge at the 7th or 8th fret), checking nut slot depth relative to the first fret, verifying the gap between frets and a fret rocker, measuring the clearance between the truss rod and its channel, and checking the gap between the top plate and braces during glue-up. They transform subjective visual gap assessments into precise, repeatable measurements. ## Selection Guide A standard automotive feeler gauge set from any tool supplier works perfectly for lutherie. Metric sets with blades from 0.05mm to 1.0mm in 0.05mm increments are the most useful. Brass feeler gauges are available and are non-magnetic, which can be helpful around pickups, but steel sets are perfectly adequate. Budget 5 to 15 dollars for a quality set. Keep the blades clean and lightly oiled to prevent rust. ## Tips - Slide the gauge blade into the gap gently. It should pass through with light drag,…