THE SAWMILL 



111 



CHAPTER V. MANUFACTURING INDUSTRIES. 



PARAGRAPH XIX. 

 THE SAWMILL. 



(A) THE SAW. Three kinds of log saws are used: — 



1. Straight saws, viz. :- Vertical straight saw; gang saw; horizontal frame saw. 



2. Circular saws, viz. :- Solid tooth single saw; solid tooth double saw; inserted tooth saw. 



3. Band saws, viz. :- Single cutting band saw; double cutting band saw; horizontal band saw. 



I. Straight saws. 



(a) Single vertical straight saw. At the toothed edge this saw has a thickness of from 5 to 10 gauge. 

 Its blade is 8 inches wide and at least twice as long as the log diameter. 



A short blade yields the finest work, since it can be spanned more tightly. 



The gauge along the back should be finer than the gauge along the cutting line. 



The saw is able to cut, usually, logs having up to four feet diameter. 



The saw cuts by the down stroke while the log is moved against the saw during the up stroke. 



The saw is spanned in a guide frame and is given as many inches inclination toward the log as the 

 feed of the carriage per stroke amounts to. If the saw were not inclined, ail the work would be done 

 by the lowest teeth. 



The usual set is still the spring set and not the swage set, although the latter is sure to be superior 

 in efficiency. 



Usually the ends of the boards are not sawn through but are held together by the "comb," which 

 is finally split with the a.xe. 



In filing mill saws, obtain sufficient pitch of teeth to prevent saw from kicking out of the cut. Too 

 much pitch, however, causes chattering. 



Gullets must be kept carefully rounded. 



(b) Gang saws. They are used in large mills for inferior and small logs. 



The best make is Wickes Bros'., Saginaw, Michigan, and Wilkin Challoner Co., Oshkosh, Wisconsin. 

 Particularly strong foundations are required. 



The usual type of sawmill found in Germany 

 (Mahr, Darmstadt, Germany). 



The largest sawmill in Europe, employing 20 singfle-log gang-saws, 

 all belt-driven from one shaft. 



