ABC of the Steel Square and Its Uses

by Fred. T. Hodgson

Fig. 7.

“The rise is the distance from the top of the ridge end of the rafter to the level of the foot. From C to D, [Fig. 7].

“The pitch is the proportion that the rise bears to the whole width of the building. The illustration, [Fig. 8], shows one-third pitch; the rise of 8 foot being one-third of the width of the building.

Fig. 8.

“The cuts or angles of a rafter are obtained by applying the square so that the 12-inch mark on the body and the mark on the tongue that represent the rise shall both be at the edge of the rafter. The illustration, [Fig. 9], shows 8 foot rise, the line A the cut for the ridge end of the rafter and B the cut for foot end.”

Fig. 9.

The portion of square shown at [Fig. 10] exhibits the tool having on its face a table of the run, rise and pitch of rafters, being specially figured for this purpose, and shows the measure of the rafter for any one of seven pitches of roof based upon the length of the horizontal measurement of the building from the center to the outside.