Immediately after use, close fanned out feeler gauge blades. This should be done by grouping smaller blades against the consecutively larger sizes for support. This will prevent the thinner blades bending when they are closed into the case.
Feeler gauges should be cleaned with an oily cloth before storage to prevent rust.
Wonkee Donkee recommends that you keep the blades closed at all times, other than when in actual use, to prevent damage. Open – Measure – Close.
The blades should only be out for as long as it takes to measure or set the gap. Tighten the adjusting screw, if there is one, for additional security.