A Practical Treatise on the Steel Square and Its Application to Everyday Use; Being an Exhaustive Collection of Steel Square Problems and Solutions, "Old and New," with Many Original and Useful Additions Volume 1 (Paperback)

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1913 edition. Excerpt: ...of the common rafter on left gable, 9 inches on the tongue, the run of common rafter on front gable, measure across and you have 15H, which is, practically speaking, 15 feet 10 inches. This is the run. You now take this on the blade, and the rise, 8, on the tongue, measure across and you get 17, which we will call 17 feet 9 inches, the length of the valley. Deduct the diagonal of half the thickness of the ridge, e.g., if the ridge is 2 inches measure across from 1 to 1 on the square and deduct from the total length. The 15 feet 10 inches and the 8 gives the plumb and bevel cuts, the bevels to fit the ridge on the back of valley. Take the length of common rafter on front side, 15 on the blade, and the run of the common rafter on front gable, 9 feet, on the tongue, which is the distance it is carried to the right to strike the ridge H; the tongue gives the cut for main ridge, and the blade the cut for ridge H. Now as to the jack rafter on the front side of left gable, we divide the length of the common rafter, 15 feet 3 inches, by the number of openings, as previously shown, which gives us the length of the shortest jack, etc. The bevel across the back will be found by taking the length of common rafter, 15 inches, on the blade, and the run of the common rafter on the opposite side of the valley, 9 inches, on the tongue. The blade gives the cut. The down bevel will be the same cut as the ordinary rafters at the ridge. The other jacks will be found in like manner for the other pitches. Hence the rule to find the bevel across the back of jack rafters when the whole of the roof is the same pitch. The length of common rafter on blade, its run on tongue; blade gives the bevel. When the hip or valley runs between two different pitches take the...