26 BULLETIN 718, V. S. DEPARTMENT OF AGEICULTUEE. 



Ill ordering a circular i^aw be careful to give the following speci- 

 fications in detail : 



1. Din meter of the saw in iuolies. 



2. Rij:ht or left baud mill. 



3. Gauge of saw at center aud at rim. 



4. Number of teeth in saw. 



5. Style or pattern of tooth, solid or inserted. 



6. Diameter of mandrel hole, diameter of pinhole and distance, center to 

 center of pinholes. 



7. Number of revolutions of saw per minute, while in cut. 



8. Greatest feed in inches per revolution and kind of feed. 



9. Species of timber to be sawed. 



10. Spring or swage set. 



11. Horsepower available and size of belt pulley. 



12. Engine speed and size of mandrel pulley. 



The size of the saw should be governed by the size of the logs to 

 be cut, regardless of the amount of power used. The diameter of the 

 saw should be approximately one and a half times the diameter of 

 the largest log to be cut. For instance, a 36-inch log needs a 54-inch 

 saw, a 40-inch log a 60-inch saw. The width of the widest board 

 which a single circular saw can cut equals the radius of the saw 

 minus 3 inches; that is, a 60-inch circular saw can cut a board or 

 plank 27 inches wide. ■, 



HANGING A SAW. 



Set the saw plumb and true. Set the saw guide and adjust the 

 guide pins clear of the teeth and just touching the plate. This 

 should be done while the saw is in motion, care being taken that the 

 pins do not push the saw to one side or rub hard enough to cause 

 friction. After scre^ving the saw up betw^een the collars examine 

 the front or log side of the saw to make sure that it is flat. Never 

 attempt to run a saw that is dishing on the log side, as it will be 

 sure to draw toward the log and be ruined. It does not follow that 

 because one saw works well that another will do so on the same 

 mandrel, or that two saAvs will hang alike on the same mandrel. 



It is absolutely necessary that the saw mandrel sliould be perfectly 

 level, so that the. saw will hang exactly plumb. If it is found to be 

 rounding on the log side, cut a ring of paper about half an inch 

 wide the size of the collar on the outside, oil it, and stick it on the 

 face of the tight collar around the outer cage. Then cut another' 

 ring of paper the same width, making the hole the same size as the 

 hole in the saw, put this small ring between the loose collar and the; 

 saw, and screw up the collar. If the two rings are not enough, put 

 ill more until the saw stands straight and true. If the saw hangs 

 dishing on the log side, reverse the rings of paper; that is, put tlie. 



