106 CONSTRUCTION 



make the work of soldering easier. After preparing the surfaces with 

 solder-flux it is only necessary to place solder on the frame, lay the flange 

 on top of it and apply torch beneath. When solder melts, press flange 

 down and into exact position with a small stick of wood. It is better to 

 have flange sufficiently narrow to allow the uprights to fit in back of them. 



The same form can be used for upper and lower frames. Should 

 there be any irregularity in shape, they will both be alike, and so far 

 as strength is concerned, it will only be necessary to keep corresponding 

 defective corners parallel with each other, so as not to make any twisting 

 strain on the» glass— a force which, sooner or later, will cause it to break. 

 If the frame is too large for a board form to be laid within it, it may 

 be trued by lines drawn on floor or table to lay it over. The use of forms, 

 however, is so desirable to the amateur that we recommend having boards 

 cleated together in order to secure sufficient width. 



To test the squareness of upper and lower frames, lay them on the 

 floor, make marks at the corners and turn completely over, trying both 

 length and width in this way. Tests by carpenters' squares at corners 

 are only approximate, as the angle metal is seldom perfectly straight, 

 especially in lighter brass. Before leaving the subject of bending the 

 frames to right-angles, we strongly suggest that an experimental bend 

 first be made with a waste piece of angle brass. A little practice will 

 be necessary to learn just how thin a particular lot of brass must be 

 filed in order to make a good bend. 



The next step is to bore holes in the lower frame where it is to be 

 bolted through the base, countersinking for depression of bolt head, and 

 allowing enough room not to interfere with the glass. Now solder in 

 uprights to connect top and bottom frames, not melting former soldering. 



It will be observed that the glass will be supported by the upright 

 posts, but not by the top nor bottom frames. This is corrected by solder- 

 ing, about every eight inches, a small piece of brass (cut from the same 

 material) to the horizontal frames next to where the glass is to come, thus 

 giving it even support or bearing on all four edges. The pieces are 

 soldered down perfectly flat, and if high should be filed down. Before 

 the glass is finally inserted it must be laid in the frame to see that the 

 points of contact are even. Deficiencies can be made up by a drop of 

 solder on the brass, and filed down as required. 



The frame being trued up, it is now bolted through the base, aquarium 

 cement being liberally supplied in the bolt holes and between the frame 

 and the base, all surplus being immediately wiped away. 



Soldering. In these times when nearly everybody is either building 

 or altering radio sets, it would seem needless to offer any suggestions on 

 soldering. However, the chapter would not be complete without it. 



