The base body is a manufactured with the highest precision, fine-grained granite column, manufactured with the highest precision. The proven vacuum air bearing measuring slide ensures highest repeatability. With the switchable air storage, built in the stand itself, SQUARE-control can be moved and positioned easily and gently on the test plate. Vacuum-operated measuring accessories can be connected directly to the measuring device.



  • Squareness measurement system in the highest precision
  • Manual or motorised measuring
  • Easy and reliable measuring with high repeatability
  • Temperature resistant construction of fine grained hard stone
  • Well dimensioned ground fac
  • Smooth and secure moving on the hard stone plate by air bearing
  • Vacuum-accessories can be connected directly at the SQUARE-control
  • Wide range of accessories available


Factsheet SQUARE-control



Technical Data

Type Travel Squareness frontal Squareness lateral Dimensions (L×W×H) Weight Required compressed air Air consumption Measurement reading Repeatability Resolution
other variations

Squareness according to ISO (with comp.): The squareness measurement value applies to a theoretical line approx. 60 mm centrally in front of the guideway surface.

The accuracy values apply to 20 °C and stable temperature conditions (ΔT ≤ 0.2K / 24h).

For special solutions and other dimensions please contact us: Contact.



Air treatment unit SA 200

The air treatment unit SA 200 is used for cleaning and the regulation of the compressed air as well as to generate the required vacuum. A measuring interface and, depending on the application, a pressure monitoring are installed directly in the device. SA 200 is used, amongst other applications, for SQUARE-control and STRAIGHT-set.


Calibration Set for Knife-Edge Squares

Kunz precision presents a simple but unique solution for measuring knife-edge squares: Hereby the new developed lever gauge GT 31-TK is employed. The measuring probe shows a cylindrical touching surface with two markings in between which the test piece is being probed. In this way, the inner and outer leg of the test piece can be measured quickly and straightforward.



SQUARE-tool is an ingenious device for even faster and more efficient measurements, with vacuum exhaust. The positioning aid is used together with the squareness measuring devices SQUARE-line, SQUARE-plus, SQUARE-control and SQUARE-master.


Measuring Probe Mounting SQUARE

This measuring probe mounting allows to measure inner surfaces with the squareness measuring instruments SQUARE-line and SQUARE-plus in the simplest way. This simple and practical accessory consists of a temperature insensitive extension tube of aluminium or carbon fiber and a probe holder.


Measuring Probes

We have several probes in our range.


Calibration Set for Reversal Measurement

To perform a reliable reversal measurement, the squareness measuring devices SQUARE-control or SQUARE-master can be expanded with a carbon fibre probe extension.



Developed as an efficient software-programme to calibrate reference angles and straight edges, STRAIGHT-soft is an indispensable aid in the measuring laboratory, the workshop or when carrying out measurements on geometry during acceptance of machinery. For testing straightness, parallelism and squareness.