A Drill Press spins a cylindrical cutter known as a “drill bit” in a vertical axis, which can be manually advanced downward into a work piece. Major components include a base, column (or pillar), adjustable table, spindle, chuck, and drill head, driven by an electric motor. The head has an Arbor, which is a set of three handles radiating from a central hub that is turned to move the spindle and chuck vertically. We have two Drill Presses in the SOA. They are both quite similar in operation. One is a bench top model and the other is a stand-alone floor model. Some clamping fixtures to be used with the Drill Presses are located hanging on the wall behind them.
A drill press has a number of advantages over a hand-held drill:
- Less effort is required to apply the drill to the work piece. The movement of the chuck and spindle is by a lever working on a rack and pinion, which gives the operator considerable mechanical advantage.
- The table allows a vise or clamp to be used to position and restrain the work, making the operation much more secure.
- The angle of the spindle is fixed relative to the table, allowing holes to be drilled accurately and consistently.
Safety
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There is a PPE label on the Drill Press mounted above the power switch, which lists precautions for the operator. Eye protection is standard in the Wood Shop, but other steps listed must also be taken. Specifically: |
All loose clothing must be either removed or pulled back from machine. All long hair must be tied up/pulled back (note: rubber bands are located at safety glasses cabinet by the wood shop entry door). Long strings or necklaces (example is sweatshirt pull strings), and bracelets, should be removed or otherwise contained. The chuck/mandrel of the drill press spins at a very high rate creating wind, this can act like a tornado and pull loose items into it causing a potential hazard. No extraneous materials should be kept on the Drill Press worktable during operations.
Clamping Fixtures
The clamping fixtures can be used to serve three purposes: One is to provide a ridged support structure to which to clamp a work piece, to ensure that it doesn’t move under the force of the spinning cutter. Another function is to serve as a locator or reference surface, to drill repetitive holes in the same place on multiple parts. A third function is to provide a solid underlayment for the work piece, so that holes drilled all the way through, leave a clean undamaged surface where the drill bit punctures through the bottom. A simple, flat sheet with a smooth surface can also be used as a substrate for drilling, as long as precautions are taken to ensure that safety is first priority.
Example: Holes made with Twist Drills up to ¼” diameter can be made without bracing the material against a backboard, as long as the material to be drilled is large enough to keep hands 6” away from the cutter. Drill Bits larger than ¼”, begin to get incrementally more aggressive, so the work piece must be braced with a backboard. Existing Clamping Fixtures can be used, or the operator can create their own using a flat, smooth substrate, and a piece of bracing material, which is long enough to be clamped at both ends.
Power Switch
Thepower switch on the Powermatic Drill Press is a Pull on / Push off type. The operator must pull the large red ring (Button) by its edge, straight out, in order to power the machine. To turn off the Drill Press, the Red ring can subsequently be pushed in by hand or even by head if hands are occupied.
Speed Control
The Speed Control on the Powermatic Drill Press is a lever on the left side of the machine near the top. It is used to set the rotational speed of the spindle, there are reference numbers printed on the top and bottom of the drill press where the lever is located. There is also a digital readout display on the front of the machine. This shows the RPM of the spindle in real time as adjustments are made. The speed reference chart along the lever should be used to set the speed initially, and then check the digital read-out while your hands are free from the machine. The machine must be running while making speed changes. The larger drill bits typically run at lower speeds. The lever is turned counter clockwise and moved to the left for higher speeds, or to the right to slow the speed, then turned clockwise to lock the lever in position. A shop technician must be consulted to determine and set the proper speed rate.
Table
The Table of the Drill Press can be raised or lowered using the crank located at the right rear of the table itself. Near the crank is a column-locking lever, which must be loosened prior to raising or lowering the table. The mounting collar of the table is a bracket that “grips” the vertical column, and is rather like a bicycle seat “yoke” which opens slightly when you loosen the column-locking lever. To raise or lower the bed, loosen the lever by turning it counter clockwise, and turn the crank counter clockwise to lower the bed, or clockwise to raise it. Always Re-tighten the column-locking locking lever after adjusting the bed height!
The Powermatic Drill Press Table has extension wings, which can be unlocked and pulled outward on either side to accommodate larger work pieces. Each extension wing has 2 cam-clamps that swing open to unlock the wing and allow it to be pulled out to enlarge the tables’ work area. The cam-clamps are located under each wing, so be careful when using other clamps to attach items to the table. (There is a risk of damage to this system if an operator were to inadvertently clamp a fixture in an area of the extension components.)
The Drill Press Table can also be tilted for angled drilling operations. It can be rotated to the left or right all the way from zero to 90 degrees. To tilt the Table, you must loosen the lock nut located under the Table at the center, rearward edge. A 15/16” box wrench is kept on the ledge behind the Drill Press for this. Using the closed end of the wrench, loosen the locknut by turning it twice counter-clockwise. Pull out on the spring loaded zero degree-locking pin, and rotate the Table to the desired angle while referencing the angle indicator at the rear edge of the Table, and re-tighten the locknut. The locking pin only engages at zero degrees, so it will remain extended otherwise.
Arbor
The Arbor is the 3-handled crank located on the right-hand side of the Drill Press, which controls the up and down motion of the spindle and is spring loaded to retract the spindle upward. This feature simply aids in the lifting of the spindle, but it is best to control the upward motion manually, rather than simply letting go of the Arbor. Always maintain contact and control of arbor crank.
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When setting up drilling operations involving clamps and fixtures, the operator needs to set the appropriate Table height to allow the Arbor handles to clear anything mounted to the Table. |
Drilling Bits
We have several different types of Drilling Bits. Three of the most common types are: Twist Drill Bits, Spade Bits and Forstner Bits.
Twist Drill Bits are typically straight, solid metal cylinders with spiral cutting flutes going partially along the length, the remaining length being smooth. The smooth end is called the “shank”, and is the part of the bit that mounts in the Chuck or Mandrel of the Drill Press. No less than ½” of the bit should be captured by the Mandrel, and no more than the smooth part of the shank above the cutting flutes. This portion of the drill bit is more delicate and designed to cut, not withstand horizontal force.
The twist drills are readily available on top of the Blue Tool Cabinet, and range in size from 1/16” to ½” in 64th inch increments. They are kept near the battery powered hand drills for convenience to both those and the Drill Press.
Spade Bits are typically shaped rather like a spade shovel with the cutting head being a flat piece of metal sharpened with a centering point and two cutters, and the other end continuing into a hexagonal shaped mounting shank. Since Spade bits have a hexagonal mounting shank, they must be mounted in the Mandrel with care, so that the 3 jaws of the Mandrel or “Chuck” land on the flat surfaces of the bit. Spade Bits are also stored on top of the blue tool cabinet for convenience and are safer to use in a hand drill than a drill press, because they are somewhat crude and should NOT be spun at high speeds. We have Spade Bits from ¼” to 1-1/2”.
Forstner Bits bore precise, flat-bottomed holes in wood, in any orientation with respect to the wood grain. They can cut on the edge of a block of wood, and can cut overlapping holes; for such applications they are normally used in drill presses or lathes rather than in hand-held electric drills. The bit includes a center point which guides it throughout the cut (and incidentally spoils the otherwise flat bottom of the hole). The cylindrical cutter around the perimeter shears the wood fibers at the edge of the bore, and also helps guide the bit into the material more precisely. Forstner bits have radial cutting edges to plane off the material at the bottom of the hole. Some bits have two radial edges; other designs may have more. Forstner bits have no mechanism to clear chips from the hole, and therefore must be pulled out periodically.
The Forstner bits are kept in the cabinet below the Bench Top Drill Press, and they are fairly aggressive cutting devices. We have them from ¼” diameter up to 3-1/8”, and the larger they are, the more aggressively they tend to rotate a work piece. It’s therefore very important that the work piece be supported properly when using these bits, especially ones that are over 1/4” in diameter.
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We also have some special circle cutting bits and hole saws that require very specific set-ups, and you will learn about them later, if and when your projects need them. |
Mandrel / Chuck
The drill press mandrel otherwise known as a “Chuck” is where drill bits are installed, and it’s important to capture at least ½” of the drill bits’ Shank mounting area within the Chuck for safety. It is again stressed here, that no less than ½” of the bit should be captured by the Mandrel, and no more than the smooth part of the shank above the cutting flutes. Mounting a Drill bit requires first tightening the Chuck by hand, making sure the Bit is centered within the 3 Jaws of the Chuck. At this point, it’s necessary to further secure the bit in the Chuck, using the Chuck Key, which is stored in the hole on top of the Drill Press. The Chuck Key has a row of teeth around its’ circumference, which mesh with the toothed gear around the Chuck and a protuberance or “post”, that fits into a hole below the toothed gear. Mesh the gears and turn the Chuck Key clockwise to secure the bit, then remove the Chuck Key and put it back where it goes…no where else! Note that the proper amount of torque is all that is necessary it can be over tightened. If you leave the Key in the Chuck, it will become a projectile when you turn on the Drill Press. It will fly out and could hit you or some innocent bystander! Always remove it after bit installation and return it to its proper location.
Depth Stop
The Depth Stop mechanism is comprised of 2 threaded rings mounted on a vertical shaft on the left side of the machine. The shaft moves with the Arbor and the rings come to rest on a block at the bottom of the shaft by controlling the Arbor. You can set a drilling depth by adjusting the rings and tightening one against the other using some pliers which are located near the Chuck Key at the top front of the Drill Press. Always return the pliers to their storage location.
Multiple Parts Drilling
Imagine that you need to drill a hole in the same location on 100 identical pieces. You can simply mark the first piece, put it in the Jig, and locate the Jig under the drill bit. You can clamp a stop-block to the back rail on the Jig to serve as a locator or use a “Corner Jig” for the same purpose. You can even use the “Laser Indicator” to assist. The Laser Indicator is activated by a push button on the front of the Drill Press Head. When it’s on, it projects a Laser “cross” showing where the Drill Bit center will land. Clamp a stop block to the jig with a spring clamp or “Quick-Grip” Clamp. Then clamp the Jig in place to the Table. Make sure the Table is locked first. Make sure that your clamps are not “bottomed-out” or “no threads left”, and also make sure that the clamp pads are within pockets under the Table, and not positioned where they are on ribs or Table extension components. The Jig needs to be kept clean in between operations to avoid wood chips from piling up, which could affect the registration.
Clean-up
Drilling often leaves a big mess. Whenever you’re finished working at any machine, please help us out by cleaning up after yourself. Take apart any fixtures that you may have put in place, put clamps and other tools away and sweep up the area. Any effort that you make in this regard will be most appreciated by everyone. There are 4 blue Trashcans in the room. Each one has a Bench Brush, Broom and Dust Pan attached.