ALTHOUGH the standard procedure for marking off the positions of drilled holes is well known there are some aspects that deserve special attention. Chief among these, perhaps, is the general disinclination to attempt any alteration of the standard rules. Surely it should be the aim of every good marker off to simplify the work of the driller and not merely to indicate where the hole is to be drilled. Should he not study each job apart, note its peculiarities, and seek to offset these with any reasonable innovations which promise an easier drilled hole? There is no end to the assisting ways open to him. It may be an extra circle here, a line there, a few centre pops elsewhere or, perhaps, a radical departure from all accepted rules. The present writer, whose experience includes both drilling and marking off, has often adopted such expedients in his work and proposes, for the first time, to describe a few of his own origination.
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