Why is a caliper called that?

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The caliper: the universal measuring device

The caliper is one of the most widely used measuring tools. The often used term caliper is wrong, which is measured with the caliper and not emptied. In the DIN standard 862, the term slide gauge is not mentioned either, rather it is only referred to as a caliper.

Calipers are very often not named according to the terms mentioned in DIN 862. In practice, terms such as pocket caliper, clock caliper or workshop caliper are used. These are correctly named according to their design and display type. For example, a clock dial is correctly called:Caliper form A1 with line and round scale.

Measuring with the vernier caliper: simple and yet complicated

Millions of tradespeople use the vernier caliper every day without giving much thought to the strengths and weaknesses of the vernier caliper. This is also not necessary as long as the required accuracies in the report are 5/100 -1/10 mm. Above all, the introduction of the digital caliper with a digit increment (display accuracy) of 1/100 mm suggests that measurements can also be so precisely. However, this is not the case. DIN 862 specifies 2 / 100mm as the minimum error limit and this is only achieved if a defined measuring force is used to limit the tilting of the measuring arm.

Special caliper

In addition to the designs defined in DIN 862, in practice there is a series of only standardized special calipers. This ranges from vernier calipers for measuring the grooves, to built-on vernier calipers and 3-point calipers.

Although not standardized, the note “measurement accuracy according to DIN 862” can often be found in web shops. However, this is misleading. DIN does not know the term measurement accuracy at all, only the more precisely defined term error limits. In addition, the conditions under which the error limits must be reached are specified for the calipers standardized in DIN 862. Correct would therefore be to specify the error limits for each special caliper separately and not refer to DIN 862, since it is a works standard.