Measuring and Layout — FAQ
What is a thickness gauge used for?
Thickness gauges measure material thickness for quality control, safety inspections, and manufacturing verification. Common uses include checking automotive paint, pipe wall thickness for corrosion, roof membrane integrity, sheet metal sizing, and engine gap measurements.
What's the difference between ultrasonic and mechanical gauges?
Ultrasonic gauges use sound pulses to measure through coatings and from one side only, ideal for pipes and tanks. Mechanical gauges like feeler blades require physical access to both sides and direct contact. Ultrasonic costs more but offers non-destructive testing; mechanical is simpler and never needs batteries.
Can I get accurate results under $100?
Yes. Our tests show budget ultrasonic gauges achieve ±1% accuracy on steel and plastic. Automotive coating meters under $100 resolve to 0.1 μm—sufficient for detecting clear coat differences. Mechanical gauges from brands like Mitutoyo maintain factory accuracy indefinitely with proper care.
Do automotive paint thickness meters work on all cars?
They work on steel and aluminum panels but require specific Fe (ferrous) or NFe (non-ferrous) modes. Quality meters auto-detect the substrate. They cannot measure on carbon fiber, plastic body panels, or through thick undercoating. Always test on a known original panel first to establish baseline.
How often should I calibrate my thickness gauge?
Auto-calibrating ultrasonic gauges need zeroing only when switching probe types. Manual gauges require calibration checks monthly or after 100 measurements. Automotive coating meters should be verified weekly using supplied standards. Mechanical feeler gauges never calibrate but should be oiled to prevent rust that affects thickness.
Can these gauges measure through paint and rust?
Ultrasonic gauges measure through paint, rust, and coatings—displaying base material thickness only. Automotive coating meters measure paint thickness exclusively and stop at the metal substrate. Mechanical gauges measure total stack-up including all layers. Choose based on whether you need base material or coating thickness.
