130 FARM MECHANICS 



is crooked, it is almost impossible to prevent binding. 

 If a saw binds in the kerf, very often the uniform set 

 is pinched out of alignment, and there is some danger 

 of buckling the saw, so that for ordinary wood sawing 

 it is better to have the end of the stick project beyond 

 the jig. If the saw is sharp and has the right set and 

 the right motion, it will cut the stick off quickly and 

 run free while the end is dropping to the ground. 



The quickest saw frames oscillate, being supported 

 on legs that are hinged to the bottom of the frame. 

 Oscillating frames work easier than sliding frames. 

 Sliding frames are sometimes provided with rollers, 

 but roller frames are not steady enough. For cross 

 sawing lumber V-shaped grooves are best. No matter 

 what the feeding device is, it should always be pro- 

 tected by a hood over the saw. The frame should fall 

 back of its own weight, bringing the hood with it, so 

 that the saw is always covered except when actually 

 engaged with the stick. Saw-mandrels vary in diame- 

 ter and length, but in construction they are much 

 alike. For wood sawing the shaft should be 1%" or 

 iy 2 " in diameter. The shaft runs in two babbitted 

 boxes firmly bolted to the saw frame. The frame itself 

 should be well made and well braced. 



ROOT PULPER 



There are root pulpers with concave knives which" 

 slice roots in such a way as to bend the slices and break 

 them into thousands of leafy shreds. The principle is 

 similar to bending a number of sheets of paper so that 

 each sheet will slide past the next one. Animals do 

 not chew roots when fed in large solid pieces. Cattle 

 choke trying to swallow them whole, but they will 

 munch shredded roots with apparent patience and evi- 



