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EXCELSIOR MILL 



PARAGRAPH XXX. 

 EXCELSIOR MILL. 



(A) GRADES OF PRODUCT. The following grades of excelsior are distinguished:- 

 First grade:- Fine wood wool, thickness from '/jo,, inch to ' ,;, inch. 



Second grade: -Common fine wood wool. 



Third grade : — Mattress stock. 



The greatest demand is for stock \',o(i inch thick and from '/g. to Vs inch wide. 



(B) USAGE. Excelsior is used for upholstering and for packing (glassware, furniture, confectionery, <&c.). 

 It is preferred to straw owing to its greater elasticity and to its lack of dust. It is easily colored. A limited 

 amount of excelsior is woven into mattings and rugs. 



(C) KINDS OF WOOD. Basswood is best; balm of gilead, Cottonwood, and yellow poplar come 

 next. Birch, gum, pine, and spruce are used also. Frequently the core of blocks peeled on the rotary 

 veneer machine is made into excelsior. One cord of basswood yields 1,500 pounds of excelsior. 



(D) PROCESS OF PREPARATION. The wood is peeled, cut into 38-inch blocks, and the blocks 

 split into slabs 5 to 6 inches thick. These slabs are thoroughly air-seasoned under cover, and finally cut 

 into two lengths of 18 inches each. 



(E) MACHINERY. Excelsior machines are, usually, small, upright knife machines manufactured, 

 amongst others, by the American Sawmill Machinery Co., Hackettstown, N. J. The modern machine, 

 however, (made by Kline, Alpena, Michigan) is an eight -block horizontal machine consisting of:- 



I. Two sliding steel frames carrying 

 eight tool heads into which the knives and 

 the comb-like spurs are spanned. The 

 sliding frames are moved by powerful cranks 

 and pitmans on maple slides. 



II. Two stationary frames, above Ihe 

 sliding frames, each having four sets of 

 rolls; each set pressing by its rotation a 

 wood block downward against the knives. 



III. Conveyors for the shavings, falling 

 through the sliding frames. 



The operator -one man attends the 

 machine unaided — feeds the wooden blocks 

 from above into the stationary frames, 

 whilst the machine is running at full speed. 

 The comb -like spurs are cutting fine, 

 parallel lines into the bottom face of the 

 blocks; and the knives sever at each 

 feeding stroke a thin layer of wood from 

 the blocks. 



Additional machinery consists of automatic knife grinders, baling presses, cut-off saws, barkers, &c. 



The price of the machinery for a modern excelsior plant is about •v2,000. About 30 horse-power 

 are required. 



The daily capacity of an eight-block machine is 4,000 pounds of fine wood wool, or 10,000 pounds 

 of mattress stock. 



Excelsior is, usually, a by-product, and not the main product of a manufacturing plant. 



Eight -block horizontal excelsior machine, made by Kline, 

 Alpena, Michigan. 



