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Shop Tip #029
© Frank Ford 2004; Photo by FF

If you don't have one of these, you should get one. It's the classic machinist's micrometer and it has far better accuracy in the range of measuring string gauges. The now-familiar 6-inch dial or digital caliper has just enough flexibility that it can be nearly impossible to get a positive reading on a string gauge, where a thousandth can spell the difference between light an medium gauge. It takes a bit of practice to learn to read this critter, but it's a deadly accurate tool, and worth the effort. Even the least expensive do a fine job.