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The New Zealand Railways Magazine, Volume 2, Issue 6 (October 1, 1927)

[section]

“Nothing has a greater tendency to promote improvements in any branch of production than their trial under a new set of conditions.”
—John Stuart Mill.

Drills are undoubtedly the most popular and useful of all tools, and in a very crude form were used by primitive man in the Neolithic or Later Stone Age.

The exact date when the twist drill first came into use is not clear, and to attempt to state a definite date would be drawing a bow at a venture. The early lip or flat drill, which still has its uses, was the only available tool known to our ancestors.

This type of drill was a source of annoyance and dissatisfaction to engineers. It was very slow when used for drilling deep holes, and had to be repeatedly removed for the purpose of clearing the chips and cuttings. This lack of clearance engendered heat that drew the temper, and necessitated not only frequent regrinding, but also rehardening. A fast speed or a heavy feed meant certain disaster, consequently the rate of penetration was slow and tedious.

After much toil and experiment a crude type of twist drill was evolved. This was made by heating a length of flat steel and twisting it-not with the object of giving the cutting edge a workable rate, but to enable the chips and cuttings to find an easy exit when drilling deep holes and so obviate the necessity of continually removing the drill. Success was not to be so easily bought, however, and this type of drill (which resembles the present day twist bit used in wood working shops) did not come up to expectations. Practice refused to obey theory, and the chips and cuttings failed to find ready exit along the twists of the drill. Heat was again engendered, and the same vicious circle of break-downs, common to the flat drill, still remained the problem. Not to be defeated, a spiral grove drill was tried with a fair measure of success. The cork-screw like action of the spiral flute did convey the chips and cuttings from the point of the drill, thus minimising the disadvantages of the twist drill. But as speed was by no means a virtue of this type of drill the demand of the production engineer had yet to be met.