Instruction of Digital Calipers

Digital calipers are very useful measuring instruments. Nowadays, no do-it-yourselfer should be without one in hand because they are so economical. In general, digital calipers can measure from 150 mm to 200mm. The smaller calipers will measure tighter spaces while the larger ones will fit into larger work-pieces. As is well known to all , calipers are used to make external, internal and depth measurements. The external ones fit across the work (eg to measure the diameter of a rod), the internal ones measure the width of openings (eg of a cut-out being made in a panel to mount a head-unit) and the depth provision can be used to measure the length of a drilled hole. The primary use of a digital caliper is the measurement of the thickness of an item, and the external calipers can handle this measurement perfectly.

The instrument is fully closed, zero’d, then the external calipers placed so that they are a just-snug fit on the item. The reading is then made before the calipers are removed. Used in this way, digital calipers are especially useful in measuring screws and bolts to make accurate sizing of the drill-bit easy, measuring coil spring wire thickness (something that it’s important to do very accurately when comparing spring rates) and measuring sheet metal gauge. And literally hundreds of other uses! Internal measurements with digital calipers should be made only when the opening has parallel sides. If you try to use the internal measuring calipers to measure the diameter of a hole, the thickness of the internal measuring jaws will give an incorrect reading. Instead, in this situation you need to use thinner manual calipers, as described below. With the low price of stainless steel digital calipers, it’s not worth buying plastic imitations. Arguably, it’s also not worth hanging on to old-style vernier calipers :the digital readout is much quicker and easier to read, with less likelihood of mistakes being made.