SOLDERING 489 



To this list every mechanician will want to add various 

 hand tools, etc. The expense of these, however, will not, 

 as a rule, be very great at any one time, for such equip- 

 ment is usually needed for special pieces of work, and the 

 tools required can be bought from time to time as the funds 

 are available. 



Mechanical Procedures. 



A few paragraphs may be devoted to some of the most 

 elementary and useful mechanical procedures which may 

 be carried out in the shop. The first of these is soldering. 

 The metals best suited to this work are brass, copper, 

 tinned iron and wrought iron. Cast iron is scarcely suit- 

 able. Galvanized (sheet) iron is soldered readily. The 

 process is exceedingly simple, and easily carried out if the 

 parts to be soldered together are not very complicated. 

 The most difficult feature of the process is to hold the va- 

 rious pieces in the proper position until the solder can be 

 applied. This is usually best done either by tying the 

 pieces together in the right position Avith wire (copper or 

 soft iron, smooth, No. 16 or 18) or by fastening the pieces 

 down to a board or block of wood in the proper position 

 by means of small nails driven into the wood. 



A blast lamp burning gas and supplied with compressed 

 air (easily obtained from a rotary pump such as should be 

 used for artificial respiration) is the best method to be 

 used for melting the solder. A foot bellows may be used 

 to supply the air. A blast lamp exactly like the one shown 

 in Fig. 371 should be provided. 



Small articles can be soldered with a spirit lamp and 

 mouth blowpipe but this is both tedious and tiresome ex- 

 cept for the very smallest articles. Tinners and some me- 

 chanics use a soldering copper but this is a crude method 

 and often entirely unsuited for much of the work required 

 in making ordinary pieces of apparatus. But a soldering 

 copper is of service in the soldering of aluminum for which 



