The effectiveness of today's straight-flute drills undercuts traditional assumptions about the indispensability of spiral-flute drills. In some applications, a straight-flute drill is a better choice than a twist drill. Modern straight-flute drills were preceded by die drills: short, stiff tools with beefy tips for drilling hard steels. Run at a slow spindle speed and light feed rate, the die drill's strength and rigidity enabled it to make straight, round holes.
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