124 



FOREST PRODUCTS 



The usual procedure is to load the bolts on cars 55 by 53 in. in size, 

 which are rolled into steam tunnels about 45 ft. in length. The tunnels 

 may be constructed either of wood or concrete. One mill has 15 of 

 these tunnels arranged side by side with a capacity "of 9 cars, or a total 

 capacity of 135 cars, which contain the equivalent of about 100,000 

 staves 285 inches in length. 



From the steam boxes the bolts go to the stave bolt equalizer, located 

 conveniently to the stave cutter (to the left of it and about 3 ft. from it) . 

 The bolts are first peeled of all bark. The equalizer cuts off both ends 

 of the bolt to insure the desired length and make them smooth and square. 



FIG. 29. The Trevor stave bolt equalizer. 



It is provided with two circular cut-off saws about 32 in. in diameter, of 

 n-gauge, having 64 teeth and run at a speed of about 1800 R.P.M. 

 Each equalizer can turn out enough bolts for 50,000 staves daily. 



Next the bolts are cut into staves on a stave-cutter. This machine 

 has a knife usually 36 in. long and 6| in. wide, with a face ground to a 

 circle of 20 in. The bolts fit in a tumbler and at each stroke against the 

 knife a stave of any desired width is sliced off. The speed of the machine 

 is regulated as fast as the operator can feed it, 150 to 170 strokes per min- 

 ute being the usual practice. With even, straight bolts the work is much 

 easier than with split or uneven pieces. This work demands the con- 



