Tricks of the Trade 



Under this head each month there will appear 

 one or more articles describing methods 

 and short cuts in shop work practice 



Burning Holes in Patterns 



PATTERN makers and other wood 

 workers are often at their wits 

 end to find a way to make smooth, 

 tapering holes, especially in a piece of 

 wood which is cross-grained, or in which 

 the hole has to 

 run diagonally 

 with the grain. 

 Ordinarily a 

 sharp taper 

 reamer may do 

 the work, but 

 one of just the 

 right size, is 



Tapered holes accurately sized by burning 

 with wood points rapidly revolved in them 



not always at hand, and when a hole 

 of a particular size and bevel is required, 

 the taper reamer will not do the work. 



On a job recently, there had to be 

 five smooth holes, of the same size and 

 bevel, through a piece of ^-in. white- 

 wood. The holes were ^ in. at the 

 small end, and 1 in. at the large end. 

 They were bored with a sharp bit, a 

 little smaller than they were to be at 

 the small end, then beveled with a 

 sharp knife to nearly the size at the large 

 end. A piece of hard wood was then 

 turned to nearly the size and taper re- 

 quired, as shown at A. This was revolved 

 at medium speed in each hole until it 

 burned a little. Care was taken not to 

 let it burn too much. This was repeated 

 until the holes were almost the size 

 and bevel required. Next, another plug 

 B was turned the exact size the holes 



were to be when finished. Then the 

 holes were carefully finished with this. 

 It is a good plan to turn a shoulder 

 on the finishing plug so that the holes 

 may be just alike. Finish the holes with 

 fine sandpaper. — C. E. Stone. 



Tempering a Chisel to Cut Stone 

 or Bricks 



A CHISEL to cut stone masonry work 

 must be tempered to a different 

 degree of hardness than those to use for 

 other work. Before tempering, it should 

 be sharpened on an emery wheel, as 

 tempering puts a hard surface, or a sort 

 of skin, on the cutting edge, which grind- 

 ing removes to a certain extent, no matter 

 how carefully the grinding is done. In 

 grinding stone cutting tools, do not 

 grind the cutting edge with too narrow 

 an angle, but allow the edge to have an 

 angle of over 100 deg. This gives a 

 sufficient amount of metal back of the 

 sharp edge, to enable it to withstand the 

 shock of the blows. Too sharp an angle 

 on the tool edge would cause it to break 

 at the first blow. After the grinding is 

 done, put the chisel into the fire and 

 heat it to a cherry-red color, then dip 

 the point of it into cold water — holding 

 the chisel in a vertical position. Do not 

 dip it all in, but leave some heat in the 

 shank. Quickly brighten the point with 

 a file or emery cloth and watch the colors 

 closely as they travel down to the point. 

 When a light-blue is reached, dip the 

 entire chisel into cold water. It is then 

 ready to use. — W. S. Standiford. 



Mercury Used for a Thrust Bearing 

 on an Upright Shaft 



ANEW bearing is being used on a 

 generator set, wherein the main 

 shaft stands vertically and supports con- 

 siderable weight. Instead of being sup- 

 ported by collars or an end thrust bearing, 

 a small quantity of mercury is placed in a 

 pocket at the lower end of the shaft. 



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