TOOLS AND WORKSHOP FACILITIES 



Snips, scissors, forceps, long-nose pliers — the last two are useful when wiring. 



Soldering irons: 150 watt iron for tinplate work; 25 watt iron* for general wiring work. 

 Miniature hacksaw. 



Abrafile* — a hacksaw-like tool possessing a blade which cuts in any direction. Useful for 

 odd-sized and odd-shaped holes. 



In addition, one needs stocks of solder (flux-cored for preference), nuts and bolts in 

 B.A. sizes — of which 4B.A. and 6B.A. are the most important — in i and ^ in. lengths, 

 insulating tape, etc. 



The difficulty about buying ready-made metal work is that it is expensive, 

 that one has to use what one can get, and that the standard of workmanship 

 and finish may be unnecessarily good where the construction of temporary 

 or experimental apparatus is envisaged. Where a considerable amount of 

 electronic work is forseeable there is no question that plan No. 2 is more 

 satisfactory; given the proper machines it is possible to turn out professional- 

 looking sheet metalwork with very little practice. These machines are unfor- 

 tunately rather large and far from portable, and it becomes necessary — unless 

 one has access to someone else's — to have a definite workshop for them. 

 The two most important are : 



(1) ^ i //. guillotine (Plate 27.1). Sheet metal is suppUed in pieces 

 8 X 4 ft. and 6 X 3 ft. It is important to remember to order the smaller 

 size; nothing is more exasperating than, perhaps after considerable delay, 

 to be supplied with material one cannot get into the machine. 



(2) A swing-beam folding machine, for producing sharp, straight bends 

 {Plate 27.2). The 'ordinary' type of folding machine is better than nothing, 

 but is severely limited in the range of work it can perform. 



If funds and space permit it is also worth considering: 



A bench grinder so that worn or broken drills and screwdrivers may be 

 repaired. 



A bench, or pillar, drilling machine — these are really something of a luxury, 

 but their use is unquestionably conducive to speed and accuracy. 



A fly-press is also perhaps a luxury, but would show a great saving of time 

 where large numbers of holes have to be punched. In addition, a fly-press 

 can perform work not otherwise easily carried out, such as the forming of 

 louvres. 



Paint sprayer or crackling oven; the choice here depends on whether the 

 smooth cellulose or the 'crackle' type of finish is preferred. Crackle finish 

 is an excellent artifice for concealing the effects of indifferent workmanship 

 below, such as surface scratches and improperly drilled holes. Cellulose is 

 extremely difficult to brush on satisfactorily, but rather easy to spray. 

 Crackle paint is normally brushed on, then the work is put into an oven for 

 the crackling process to take place. Neither a paint sprayer nor oven are 

 actually necessary, however. There is a proprietary type of crackle paint, 

 Panl, which crackles up without oven treatment. As for cellulosing, the author 

 must confess to an affection for the humble Flit gun, though it must be 

 admitted that progress is rather slow. 



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