In order to prepare a sensitive thin sample surface of cementitious materials for the observation of microcracking under the electron microscope (ESEM), a cylindrical three-part tool made of stainless steel, is constructed. The tool enables grinding and polishing to the desired thickness of 1 mm and below, thanks to: (1) rotational circled plate with a handle, placed in the cylinder center, (2) scale, placed at the the opposite end of the samplelocation and (3) safe sample holding in the opening in the inner cylinder. Thanks to such sample surface preparation, the created digital images in ESEM are extremely clear and sharp, which enables qualitative Digital Image Analysis. The cylindrical tool is multipurpose created for polishing of smaller and larger samples, easy to handle and maintain.

In order to investigate shrinkage and microcracking of samples (d=1 mm) made of concrete and other cementitious materials, in the electron microscope (ESEM) in the early sample age (min 2-3 days old), when samples are still soft and breakable, mould is created. The mould is made of stainless steel. It consists of the bottom plate and the thin (d=2 mm) surface plates, which are fixed to the bottom plate with screws. The thickness of surface plates determines the thickness of cast samples. For experiments in ESEM, where a large number of thin (10x10x2 mm) samples is needed, the constructed mould contains 10 cells. If needed, the shape and size of cast samples can vary by removing a certain number of plates. The mould is multipurpose, very easy to handle and maintain.