Calipers - Precise measurements for the highest demands

Calipers - whether digital or analogue - are an indispensable tool in many technical and craft areas. It enables exact measurements of lengths, diameters, depths and steps and is used where a fraction of a millimetre is important.

What is a caliper gauge?

A caliper gauge is a precise measuring instrument that is used to determine lengths, external diameters, internal diameters, depths and step heights. It is one of the standard measuring tools in industrial production, mechanical engineering, metalworking, precision mechanics and even in the hobby sector such as model making or 3D printing. This measuring tool consists of a main scale and a movable slide with which the measuring legs are opened and closed. Depending on the version, the caliper has either an analogue scale with vernier or a digital display for direct indication of the measurement result. Thanks to its versatility and accuracy, the caliper gauge is one of the most important tools when it comes to checking workpieces.

Areas of application for calipers

Calipers are used in a variety of industries and fields of application. In mechanical engineering, it is used to ensure that components have been manufactured precisely and fit together perfectly. In metalworking, it is used to check the outside diameter of turned parts or the drilling diameter of milled parts, while calipers are also used in woodworking to check the exact length or depth of milled parts. In workshops, especially in automotive engineering, it is used to measure the thickness of brake pads or to check fits, for example. Hobbyists, 3D printing enthusiasts and modellers also regularly use this instrument to check components with millimetre precision or to measure prototypes.

How a caliper gauge works

The basic structure of a caliper consists of a fixed scale with a scale and a movable slide that is guided along the scale. The object to be measured is positioned between the measuring legs and the movable slide is moved so that the measuring surfaces lightly touch the object. The measurement result is displayed either on an analogue scale with vernier or, in the case of digital models, on an LCD display. If required, the measured value can be fixed in place with a locking screw to prevent accidental movement. This design allows quick, simple and at the same time very accurate measurements - ideal for routine testing in the workshop or quality control in production.

Structure and components of a caliper gauge

A caliper consists of several precisely machined parts that together enable precise measurement. The basis is the so-called main scale - a fixed, finely scaled bar on which the unit of measurement (millimetres or inches) is stamped. A movable slide slides along it, which is equipped with either an analogue vernier or a digital display panel. The vernier makes it possible to take a very accurate reading - to within two hundredths of a millimetre - by optically overlapping the lines on the main scale and the vernier scale. The lower measuring legs are used to take external measurements. They can be used, for example, to precisely determine the outside diameter of a pipe. The upper, smaller measuring legs, on the other hand, are used for internal measurements, for example to determine the internal diameter of a hole or a ring. Another component is the depth gauge, a narrow, extendable rod that is attached to the rear end of the caliper. This can be used to precisely determine the depth of a hole or groove, for example. The instrument is rounded off with a locking screw that can be used to fix the movable slide to hold the value read.

Different types of measurement with the caliper gauge

A caliper gauge can be used in four different ways to determine different dimensions:

• External measurement

• The lower measuring legs are used for the external measurement. These are opened so that the object to be measured fits between them. The legs are then carefully closed until they touch the object. As soon as the caliper is correctly positioned, the value can be read either on the scale or the digital display.

• Internal measurement

The upper, finer legs are used for internal measurements. These are inserted into an opening, e.g. a hole, and then carefully moved apart until they touch the inner walls of the opening. Here too, the value is read either in analogue or digital form.

• Depth measurement

Depth measurement is carried out using the depth gauge attached to the rear end. This is inserted into the depression to be measured until it touches the ground. At the same time, the slider is pressed down. The value determined indicates the depth of the depression.

• Step measurement

When measuring steps, the flat underside of the caliper is placed on an edge. The movable part is then moved over the step so that the height of the step is visible on the scale.

Reading a caliper gauge: analogue or digital?

With an analogue caliper gauge, the measurement result is determined using a main scale and a vernier scale. The vernier scale shows the additional decimal places to ensure high measuring accuracy. You first read the value on the main scale and add it to the position where the lines of the vernier scale and the main scale match. If you need a more detailed explanation, our guide will give you the best advice: To the guide Digital calipers make it particularly easy for the user. The measured value is shown immediately on a display - usually with an accuracy of 0.01 mm. Many models also have additional functions, such as switching between millimetres and inches or the option of setting the display to zero - ideal for comparative measurements.

Advantages of digital calipers

Digital calipers offer numerous advantages. They are particularly user-friendly, as the measured value is displayed immediately and clearly. This reduces the susceptibility to errors, especially for users who do not regularly work with a vernier. In addition, many digital models allow a resolution of 0.01 mm, which is more than sufficient in many applications. Another practical feature is the ability to set the measured values to zero at the touch of a button.

Advantages of analogue calipers

Analogue calipers also have their strengths. They are independent of a power supply or batteries and can therefore be used anywhere and at any time. They are also generally more robust against environmental influences such as moisture, dust or temperature fluctuations. Their simple mechanical design ensures a particularly long service life.

Calibration, care and common sources of error

A caliper gauge is a precision tool - and should be treated accordingly. To ensure accurate measurement results, it should be cleaned and calibrated regularly. Calibrations are particularly important if the device is used frequently or is part of a quality assurance system. Care includes cleaning the measuring surfaces after each use and lightly oiling them if necessary. In the case of digital devices, it is advisable to remove the battery if they are not used for a longer period of time. Frequent errors are caused by dirt on the measuring surfaces, incorrect positioning or tilting of the legs. The measuring environment also plays a role - large temperature fluctuations can falsify the measurement result, as materials expand when exposed to heat.

Conclusion: Digital or analogue - which caliper is right for you?

The choice between digital and analogue calipers depends primarily on personal preference and the intended use. If you value fast, convenient and error-free readings, a digital model is the right choice. On the other hand, those who value independence, robustness and classic technology will find a reliable companion in an analogue caliper. Both variants offer precise measurement results - the decisive factor is which model is better suited to your working method and environment.

Discover now!

Whether for use in industry, trade or private hobbies, you will find a large selection of high-quality analogue and digital calipers in our range.

What types of calipers are there?

A distinction is made between digital and analogue calipers, as well as calipers with a round scale (clock). There are also depth calipers for determining the depth of grooves or blind holes, for example. In our guide, you will find an overview of the types of calipers and their advantages and disadvantages.