SIR,- Mr. G. S. Bowers has raised questions under the heading “ Building Regulations ”
which should be of interest. Under the growing system of an up-town designing office remote from the fabricating works, there must be many young designers who feel they should know more about shop processes, and who would like sometimes to come down from the rarified atmosphere of mathematics to the stuffiness of the rivet oven. May I therefore reply to Mr. Bowers’ request for criticism as follows:-
(1) It can be agreed that holes in cleats are punched more cheaply than they can be
drilled, because they a,re through single thicknesses. But even where fabricators have a free hand either to drill or punch girder work, they always drill. This is not because of a tender conscience regarding local damage around punched holes, but because it is quicker and cheaper. Each punched plate requires separate marking out, and when the plates are assembled for riveting, the alignment of holes is a gamble, necessitating drifting of perhaps 25 per cent. before rivet tails will enter.