The first drill presses were used two centuries ago to cut metal with repeatable accuracy. That they were hand-cranked is no great disadvantage: gear ratios do much to multiply force, and it's relatively easy to hold thousandths of an inch on repeated cuts. The drill press gave shape to precision machining.

Things making up a drill press: a base to add stability/accept bolts, a column to elevate the motor, a motor, a deck to hold work, a spindle to raise and lower the drill bit, and a chuck to turn the drill bit. The angle of the deck relative to the chuck determines the angle of the cut. As it was two centuries ago, force is most often multiplied by a belt between two spools. A drill press is an easy thing; tools are easy things.

The material determines the cutting speed. Softer materials bear higher speed, and vice versa. To adjust the cutting speed, place the belt across a different pair of spools at the top of the drill press (you'll notice that both spools are actually compound, of stacked spools staggered in size). If there is no label explaining the gear ratios, look at whichever spool-set is directly above the chuck. The smallest spool will turn the chuck fastest but with the least torque. Unplug the thing first.

Clamp your work in place securely. Tie back your hair. Don't wear baggy clothes. Use cutting oil if you're drilling metal. Protect your eyes. Pay attention.

Your cutting speed and pressure are appropriate when the material exits the drill's flutes unbroken. Your goal is to see curls--not shreds of metal smoketrailing in random directions. Similarly, ease up if the drill bit whines and stops turning.

 

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Drill" press` .

A machine for drilling holes in metal, the drill being pressed to the metal by the action of a screw.

 

© Webster 1913.

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