Again lay on a box of doors with screwed loops. In order to mark opposite recesses after the sample, the loops must be screwed to the box. After that they are removed from the loops, and the door box is installed in the level in the interior opening. The top of the canvas is blocked by wedges, and a crossbar is laid below to avoid a skew. If there is no lower crossbar, then the boxes are attached to the ceiling and walls using anchor bolts. Their hats can be scored into wood by 1 mm, and then putting.