1:35 Protitankové betonové zátarasy - jehlany, Set I

Concrete pyramids as a road block

Obstacles of this shape were built by armies wherever tracked vehicles had to be stopped and the terrain could not be relied on. A truncated pyramid of cast concrete was meant to lead the track upwards, expose the thinly armored belly and force the crew to detour into a prepared field of fire. The set holds five resin castings and is designated Set I.

Separating the casting from the casting block

Resin castings are cast in an open mold, so there tends to be a sprue gate remnant on the underside. It cannot be snapped off, it would crack unpredictably. Use a cutting saw with a fine tooth or a cut-off disc and run the cut a few tenths of a millimeter above the intended edge, then level the remainder with a flat file laid against glass or a tile, so that the base stays flat. Work with respiratory protection, resin dust is fine and settles in cavities.

Bringing the texture back to a sanded spot

Sanding takes away the roughness of the concrete, and a smooth patch is more visible on a finished diorama than the joint itself. The texture is brought back with a thin coat of modeling putty stippled with an old brush with stiff bristles, or by dusting fine sand into paint that is still wet. The sharp edges of the pyramid, on the other hand, should be knocked back lightly; a cast edge is too perfect at this scale.

What a finished scene looks like

The pyramids were never built in a precisely aligned row. Sink them to uneven depths into the soil, tilt one, leave another undercut by water. It is precisely the irregularity that gives the barrier credibility and brings an otherwise empty edge of a diorama into play.