SMALL SAWMILLS, THEIR EQUIPMENT, ETC. 11 



THE MILL AND MILLING. 



If the operator is already provided Avitli a mill, the size of his 

 operations will depend on the power and capacity of that mill. If 

 he plans to purchase a new mill, he should figure on one with the 

 power, capacity, and equipment necessary to meet the requirements 

 of his capital, his liiarket, and his logging equipment. Lack of suffi- 

 cient power, even for driving the saw, is a common handicap for 

 small mills. An effective 25-horsepower engine will, if properly 

 handled, keep a circular saw Working to capacity and at the same 

 time will run a small planer and edger. 



The type of mill in most general use in Forest Service District 4 

 is one cutting from 2,000 to 20,000 feet per day. The following dis- 

 cussion, therefore, will be confined to two classes of this type, one 

 cutting from 2,000 to 10,000 feet per day and a heavier one cutting 

 from 10,000 to 20,000 feet per day. The smaller mill will be called 

 Class A, and the larger. Class B. 



Sawmills are generally classified as right and left hand mills, 

 according to whether the log passes to the right or to the left of the 

 saw, viewed from the front. In ordering equipment for an old mill 

 it is always necessary to specify whether the equipment is. needed for 

 a right or left hand mill. 



Portable mills are usually equipped with rack and pinion or 

 cable drive, and friction or belt feed or a combined belt and fric- 

 tion feed. Shotgun feed is not used in small mills. The variable 

 friction feed is so called because the sawyer can vary the feed to cor- 

 respond with the power or the size and species of timber to be cut, 

 easing down on knots and frozen timber and increasing the feed at 

 will. With the same power a variable friction-feed mill is said to 

 cut from 25 to 40 per cent more than a belt- feed mill. There are no 

 belts or springs to break or give trouble. The belt feed is a combi- 

 nation of belt and flat face frictions so arranged that the feed and 

 gig back frictions are continuously driven in opposite direction by 

 an endless belt direct from the mandrel. A single lever operates the 

 feed and gig back by shifting the bull wheel from one friction to 

 the other. The shaft of the bull wheel has a pinion on the opposite 

 end which operates the wire cable drum, doing away with all inter- 

 mediate gears and securing a strong direct drive for the carriage. 

 The friction shafts have babbitted boxes with screw adjustment to 

 take up the wear in the frictions, and a substantial idler is provided 

 to keep the endless feed belt always tight. Wire cable or rack and 

 pinion drum can be used on both belt- feed and friction-feed mills. 



" Never buy anything because it is cheap " is a form of advice that 

 applies very particularly to a sawmill. Going a little further, it 

 might be laid down as an excellent business maxim : Never buy an 

 old second-hand mill, no matter how cheap it can be purchased. Ee- 



