A
a1
X
5) Rotate the laser 90° anticlockwise so that the cross beams
will pass through c1 on the table, and the forward laser beam
passes through the marks a1, and b1 on the walls A, and B
respectively.
6) Mark as c3 the center of the side vertical beam on the wall C,
at the same height of point c2. (see figure # 8 ).
22
C
X
c2
5m
c1
X
2.5m
Figure # 7
B
b1
X
2.5m