SHINGLE MILL 



149 



PARAGRAPH XXVI. 

 SHIXGLE MILL. 



(A) iM.-\TERI.^L. Breasted, shaved, rived, or rifted shingles (meaning hand-made) are used in the 

 baciiwoods only. In the Southern Appalachians, shaved shingles made of chestnut cost -52 per 1,000 pieces, 

 while so-called boards, two feet long and six inches wide, split 

 from white oak, cost ••^'3 per 1,000 pieces. Rived cypress shingles 

 are split with the tangent (not with the radius) along the 

 Southern coast. 



For machine-made shingles are used: — 

 On the Pacific Coast, red and white cedar. 

 In the Lake States, white pine, white cedar, spruce, 



Norway pine, and hemlock. 

 In the South, cypress, longleaf pine, and shortleaf pine. 

 1,000 feet b. m. in the log yield 11,000 shingles. 



(B) DURABILITY. The durability depends on the climate, 

 on the pitch of the roof, and on the size of the face which 

 the shingles offer to the weather; it is said to be for:- 



White pine, rived, 20 to 25 years. 



White pine (heart), sawn, 16 to 22 years. 



White pine (sap), sawn, 4 to 17 years. 



Chestnut, rived, 20 to 25 years. 



Cedar, sawn, 12 to 18 years. 



Spruce, sawn, 7 to 11 years. 



The manufacture of rived sugar pine stiakes in tfie 



(C) SPECIFICATIONS. The usual size of sawn shingles Sierra Nevada. 

 is:- 16 inches or 18 inches long; 4 inches wide; \,; inch thick 



at small end; -o inch thick at butt end. A bundle of shingles contains 250 pieces, is 20 inches long 

 and has 24 tiers. 



A carload of white pine shingles, weighing 22,000 pounds, contains 70,000 16-inch shingles; a large 

 car of red cedar shingles contains 170,000 pieces. 



One thousand shingles cover 100 square feet of roof, each showing 14"4 square inches to the weather. 



A rule for the number of shingles required for a roof is: -.Ascertain number of square inches in one 

 side of roof; cut-off the last figure, and the result is the number of shingles required for both sides of 

 the roof. In this case, each shingle shows 20 square inches to the weather. 



Shingles are usually laid to show 4 inches of their length, which arrangement yields, in 16- inch 

 shingles, a quadruple layer of shingles on the roof. The higher the grade of the shingles and the steeper 

 the roof, the larger is the weather face permissible. 



(D) MACHINERY. The machinery (Challoner Co., of Oshkosh, Wise, 

 leading manufacturers) used in a shingle plant consists of: — 



I. Drag saw, either driven from a countershaft or acting directly 

 from the piston, cutting the logs into shingle lengths. 



II. Bolter, a circular saw cutting the round blocks into bolts, the 

 thickness of which equals the width of thes shingle. Bolts split with an 

 axe yield a better grade of shingles but cause a large waste of timber. 

 A knot saw may be used after bolting to remove knots, rot, sap, &c. 



Drag saw. Defiance Machine Works, 

 Defiance, Ohio. 



