Checking squares are made in G25 grey pearlitic structured lamellar cast iron ideal for checking mechanical components and for clamping onto work stations; they have 14mm T-slots with precision ranging from H7 to H12.
The surfaces of the square are machined according to standard to DIN 875.


Squares are accessories used when placing materials to be machined on movable boring and milling machines. They are made in G 25 m- G30 grey pearlitic structured lamellar cast iron and can be divided into two large categories:

1. Open-structured squares: these are characterised by an L profile with two or more ribs positioned behind the work surface with the function of making the structure rigid by directing the applied forces onto the base; thanks to this type of design, interesting results are obtained from the point of view of weight, since this component has a greater impact on the final cost of the product. This type of material is suitable for dimensional checks on finished parts and for small-scale chip removal.

2. Close-structured squares are composed of a box structure which clamps the work surface to the base thanks to ribs that guarantee maximum rigidity and an excellent dispersion of vibrations deriving from mechanical machining processes. Ideal for rough-machining and placing magnetic surfaces of any shape, size and weight.

The squares can be customised from the point of view of size and supplied with 12 to 36mm T-slots as in table DIN 650 with H7 and H12 tolerance.
More than one item can be used for large squares to form the required size; this type of square is very versatile since the modularity of the structure allows it to be used in many types of clamping operations.

The surfaces of the square are machined according to standard DIN 875.

As an alternative to our standard products shown in the catalogue, G.Bonanomi can also produce any size, using any material, to satisfy all the needs and requirements of the customer.