EcrosTechWiki | Woodworking / A Home-Made Drill Press

Why do I Need a Drill Press?

I've never before owned a drill press. Even at school, where I often used a drill press in metalwork class, I can't recall using one for wood. We were issued a hand brace (this was a long time ago). All the carpentry I've done, fine and rough, and the small amount of furniture making, has come out OK with a hand-held power drill. If I need a hole to go straight and true into a piece of wood, I either get help sighting it or I use a combination square to establish a line and match the top edge of the drill to that. Two things made me decide to make a drill press. First, YouTube decided that I should watch Tamar's "Scrap Wood Trivets" video. Apart from how cute it is that she has her "minions" (daughters) do the sanding, the trivets look like an approachable project for a beginner and the results could make acceptable gifts. But, a drill press is clearly needed to make the holes for the brass rods. Second, there are plenty of videos on YouTube of people making their own drill press and this also looks like an approachable project. Plus, it will be interesting to come up with my own design. Many of these videos also show how the drill press can be adapted for other uses, including a wood lathe ?, a drum sander and power sanders of various sorts such as a spindle sander and a disk sander. This adds to the interest of the project. I've already found a need for something like a drum sander to flatten my coasters. A spindle sander may come in useful for inside curves that I can't manage on the "toe" of my belt sander. I don't see a need for a wood lathe, something else I've never used, but I'll include that in the design just too see how it turns out.

The Column

The column of a drill press provides support for the head and the table. Usually, it mounts on a base which rests either on the floor or on a bench. To make my drill press more compact and easier to store when not in use, I decided not to have a base but instead to fix the column to some convenient vertical surface, such as the side of a bench. It is made in the form of a broad channel with 12 mm Baltic birch plywood at the rear that is rabett jointed to ¾" thick poplar strips on the sides. The outside dimensions are 6" wide by 2" deep. At the top, four ball-bearing drawer runners are mounted with screws, two on the back and one on each side. The moving parts of the runners are fixed, also with screws, to a 1" thick wood block made from ¾" poplar glued to a piece of 6 mm plywood. This block therefore slides up and down and will carry the head. The lower part of the channel is reinforced with a second layer of 12 mm plywood. A third layer is made of a wide central piece and narrow strips at the sides, each undercut to leave a slot in which a 5/6" T-bolt can run. The idea is that the drill table will be fixed to a board that sits in the channel on top of these layers and that will be secured to the column by T-bolts and wing nuts. Down the center of the column, holes for #12 flat-heat screws are drilled every 2" through the three plywood layers. Any or all of these can be used to attach the column firmly to its mounting surface.

The Head (a Corded Electric Drill)

Normally, the head of a drill press includes a motor, changeable belts to couple the motor to the shaft at various rotational speeds, the shaft itself that carries the chuck and a handle that moves the shaft down and up. I just used a corded electric drill. The whole thing moves when I pull and push on the handle. It has an electronic speed control and can be locked on at full speed. To keep the drill out of the way when setting up a workpiece, it needs to be pulled up against gravity. Other people who make drill presses like this incorporate springs to do this but my idea for this did not work out, in part because I could not find suitable springs. I used what I thought would be a temporary solution involving bungee cords attached to the rafters overhead. Although it looks rather dumb, it works extremely well and I have no plan to change this. First, the cords are long in comparison to the travel of the head, so the upward force is fairly constant. Second, by detaching one of the cords, I can lower the drill onto the workpiece with only part of its weight, which can be useful during setup. Third, when I disassemble the drill press the cords make this much easier by carrying the weight while I remove the screws.

Drill Table

The drill table's purpose is to support the workpiece at the appropriate height and angle while the hole is drilled. Mine can move up and down, but it cannot swing to the side or tilt at an angle. As already hinted at, a ¾" poplar board at the back of and below the table slides in the lower part of the column and is held at the desired height by T-bolts running in slots built into the column. A crosspiece attached to the top of this board supports the back of the table. Another crosspiece supports the front, and this is, in turn, supported by angled braces running to the bottom of the back board. The table has two sidepieces attached to these crosspieces. Between them, under the drill head, is a removable plate of ¾" MDF. This can easily be discarded and replaced if it gets damaged by drilling. It can also be swapped for a special-purpose jig of some sort, for example to turn the drill press into a spindle sander. The sidepieces each include T-tracks that can be used to mount hold-down clamps.

Depth Gauge

Although clearly an essential feature, my depth gauge was an afterthought. It clamps, somewhat precariously, to the left side of the column. A projection prevents the drill head from moving down below the set point (as long as you don't pull down too hard). I stuck a few inches of self-adhesive measuring tape onto it. To set the depth of a drilled hole, I lower the drill (by removing one of the supporting bungees) until the drill bit contacts the workpiece. Then I slide the depth stop down until the bottom edge of the sliding block that supports the corded drill is at the desired depth reading on the tape.

In the photograph at right, the depth is set to half-an-inch. The drill bit is resting on the surface of the workpiece. Because it is a Forstner bit, one of the radial cutting edges is placed on the wood as this defines the flat bottom of the drilled hole. If the center point were used, the hole would be too shallow. With the bit in this position, the depth gauge is adjusted so that the bottom edge of the drill head support is level with the half-inch mark on the measuring tape. The support can now move down by this half-an-inch before it contacts the projection of the depth gauge. Ideally, it would not move further, but because of the rather flimsy clamping mechanism, if I pull down hard enough (or the drill breaks through and drops suddenly) then the gauge will slide down the column. If I think this may happen, I can put an auxiliary clamp from the front of the gauge to the back of the column, which does not look so neat, but does the trick.