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Shop Tip #159
© Frank Ford 2006; Photo by FF

To get an accurate reading with digital calipers, it's a good idea to squeeze the blades against the part to be measured.  If you use the thumb wheel or grip,  you can really see the flexibility in the caliper as it influences the reading, and you can easily be off a couple of thousandths depending on how wide the caliper is open and how hard you're pushing.