SHOP-PRACTICE AND ERECTION'. 2/7 



ness of joints, as in stand-pipe work, being considered as 

 having been provided for in the natural tendency of such 

 joints to close by rusting after erection, and to what extent 

 this practice is considered legitimate may be inferred from 

 the following, taken from an article on painting, and from 

 Prof. Pence's work, "Stand-pipe Accidents and Failures": 

 " The methods of painting stand-pipes are subject to as much 

 variation as in other exposed structural metal-work. Some 

 require that the inaccessible surfaces shall receive two coats 

 of red lead, while others allow the omission of paint from the 

 faying surfaces of the seams to permit the joints to rust." 



Again, according to recognized authorities, in forging a 

 rivet, the color, indicating its temperature, should be about 

 an orange red, and with steel rivets, with a tendency to rapid 

 cooling, at this temperature the larger rivets, especially 

 hand-driven, are so cold and tough before they are driven 

 completely home and the head forged, that it is difficult to 

 insure a perfect filling of the rivet-holes, and the requisite 

 closeness of the joint, where rivets of large diameter are 

 used, and for which reasons, in preparing the table given in 

 the chapter on Riveting, these considerations were given 

 weight. In the mention of this table, it may not be out of 

 place here to refer to the dimensions and relative strength of 

 the double-butt strap-joint, and to point out that while fully 

 recognizing that the full strength of such a joint has not been 

 developed, the necessity for such excess strength over and 

 above all the other joints, both single, double, and treble 

 riveted, did not seem necessary or particularly desirable. 



Machining: Punching and Rolling. After the plates are 

 laid off and bevelled, the punching of rivet-holes should be 

 done, and away from the surfaces to be in contact. Plates 

 not exceeding f inch in thickness may be punched with 

 sharp and well-conditioned punch and dies, either singly 

 or preferably by a power-machine employing several such 



