58 



FARM MECHANICS 



qualifies a workman to fit a nut according to the place 

 the bolt is to occupy. 



Generally it is desirable to have nuts fit very snug 

 on parts of machines that shake a good deal, and this 

 applies to almost all farm machinery and implements. 



Ordinarily a horse rake is supposed to travel steadily 

 along like a cart, but the ground is rough and in practi- 



Figure 89. Wagon-Box Brace. It is offset to hold the rave and 

 to brace the sideboard at the rear and the front ends and some- 

 times in the middle of light wagon beds. 



Figure 90. Two Plow Clevises and a Plow Link. 



cal use the nuts loosen almost as soon as haying com- 

 mences. 



Some farmers make a practice of riveting bolt ends 

 to prevent nuts from working loose. When the bolts 

 have square heads, this practice is not objectionable, 

 because with two wrenches a nut. can be twisted off 

 over the riveting, but a great many bolts have round 

 heads and very short, square shanks. Theoretically, 

 the shanks are driven into the wood firm enough to 

 prevent the bolts from turning. Practically this 



