226 SCIENCE OF SUCCESSFUL THRESHING 



A Split Box is Babbitted in the same manner except 

 that strips of cardboard or sheet-iron are placed between 

 the two halves of the box and against the shaft to divide 

 the babbitt. To allow the babbitt to run from the upper 

 half to the lower, cut four or six V shaped notches, a quar- 

 ter of an inch deep, in the edges of the sheet-iron or card- 

 board which touch the shaft. Insert three or four thick- 

 nesses of cardboard called "liners" between the halves 

 of the box to allow for taking up wear. Bolt the cap on 

 securely before pouring. When the babbitt has cooled, 

 break the box apart by driving a cold chisel between the 

 halves. Trim off the sharp edges of the babbitt with a 

 round-nose chisel, cut oil grooves from the oil hole toward 

 the ends of the box and on the slack side of the box or the 

 one opposite to the direction in which the belt pulls. The 

 shaft may be covered with paper, as explained for a solid 

 box, but if this be not done, the babbitt should be scraped 

 to fit the shaft properly. 



The ladle should hold eight or ten pounds of babbitt 

 metal. If much larger it is awkward to handle and if too 

 small it will not keep the metal hot long enough to pour a 

 good box. A cast-iron ladle will keep the metal hot longer 

 than a wrought-iron or steel one. The 20 bar cylinder 

 boxes each take about six pounds of metal, and the 12 bar 

 cylinder boxes each take two to three pounds. If no putty 

 is at hand, clay mixed with machine oil to the proper con- 

 sistency, may be used. Use the best babbitt you can ob- 

 tain for the cylinder boxes. 



