Precision Drill Press Table.



Before long, you'll run across a boat project that you will have to drill a series of holes in. And nothing says "sloppy project" like a bunch of off-center holes. As carefully as you try, it is virtually impossible to drill a series of holes accurately by using a ruler and center punch.

What is needed is a method of ensuring accurate-repetitive holes, and this table is just the thing that can accomplish the task. While it might at first, simply look like a nice drill press table, the fence has a bit of magic behind it. The fence is constructed from Incra-brand fence track, and anyone familiar with it will know about it's precision alignment characteristics. For those of you that don't, I'll explain it here.

There are three components of the fence; the Incra Track, Incra Shop Stop, and a home-made Track Mount as shown here. The stop rides along the fence and engages in a precision tooth system that provides adjustability in 1/32" increments. The hole accuracy comes from the ability to measure from hole-to-hole (or edge-to-hole) using the Shop Stop, then moving the prescribed distance for the next hole. The Shop Stop is held in precise alignment by the meshing of the track-teeth along the fence.

The teeth are spaced 1/32" apart, along the entire length of the track, which allows for fine adjustability. Incra claims a 1/1000" (that's 0.0001) accuracy between the teeth. The tracks themselves are made of extruded yellow anodized aluminum and attach with T-Track hardware. The tracks are available in 18", 36", and 52" in length. A T-Track can also be found along the front of the track. Lastly, the top of the track features a sliding scale to aid in positioning.

This photo clearly shows the track teeth on the backside of the track, and how the matching teeth on the shopstop engage.

The sliding scale merely provides a rough guide to move the Shop Stop to the correct area; howver, the meshing of the teeth between the track and stop is what provides the accuracy.

OK, so where can I buy one? It's incredible, but you can't; at least, as of this writing, I know of no drill press table that comes with this system as a package deal. Rather, you need to build your own fence, using the Incra Track that is available. You can also build your own drill-press table or purchase a table from one of the woodworking manufacturers. Several table manufacturers come to mind; Hartville Tool (www.hartvilletool.com), Woodpeckers Inc (www.woodpeck.com), Peach Tree Supply (www.ptreeusa.com) or Rockler (www.rockler.com). If you purchase a table, two things come to mind. First, check the T-Track bolt size, as some use 1/4" dia, and some are 5/16" dia bolts. As well, the distance between track slots will differ, and both of these will require you to change the fence dimensions slightly from the drawing (dimension X and Y below).

I built my own table, but I will provide details on the track fence first, as this is the most important part of the system. And if you purchase a table, its the only thing you have to add.


The Fence.

Since the fence itself is purchased from Incra, the only need is to determine how to attach the fence to the table. This is accomplished with a strip of furniture-grade particle board; 1 1/8" thick as shown in the drawing below. Huh? Where can you find 1 1/8" particle board? At Lowes for one. Go to the section in Lowes where the stairs supplies are; what you want is a particle board step, which oddly enough, is 1 1/8" thick. You can use standard particle board, but 3/4" is the common thickness, and that is not quite enough to make a solid mounting board. Also, the garden variety particle board is not "furniture-grade", and has much larger particles, resulting in a rougher finished project. Furniture-grade uses finer wood particles, and machines much better.

You will also want to determine the width of the fence and the board. My design uses two 18" Incra Track sections, butted together in the center. Since the tracks slide on the fence, I can open the tracks at the drill point if I need to drill close to the edge. You could use a single 36" Incra Track if you wish, and if so, you can get by with a 36" long board. Otherwise, you'll want a 40" board to give the tracks support if they are separated.

Dimension X and Y are dependant on the width of the T-Slots in your drill table. Mine T-Slots were 15" apart, so my dim X would be 14 1/4", and my dim Y would be 12 1/8". The two slots in the top of the mounting board allow for lateral movement as well as a slight twist to be achieved with the fence. In addition, it results in an easier install and removal of the fence.

The Incra Track itself attaches to the fence with the use of T-bolts as shown. Of importance is the thumbscrews for the fence. As there is limited clearance, use 1" dia or smaller, otherwise the fence will not lay flat on the table.

 

The fence attaches to the table with the use of "Moby" Cams, Hartville # 10600. However, any alternate T-Track clamping mechanism you wish to use will suffice. One item to be aware of is that the drill press turret handle can hit the clamp should it be too high. The Moby Cams keep the clamp low and out of the path of the handle as well as out of the way of the Shop Stop.

 

As I used 18" sections of the Incra Track, which allows the track to be separated at the drill point for close-in drilling. Again, should you not need this feature, you can use a single 36" section of Incra Track.


The Table.

You can skip this section if you have purchased a table. If not, I'll show you how easy it is to build one. For the table I used a piece of plain old 3/4" laminated shelving material. After cutting the shape, I banded the edge with laminated edging; hot-melt glued with an iron.

I like Hartville Tool's #10597 T-Track as it has serrated outside surfaces, while most T-Track has smooth surfaces. If you epoxy the track into the table (recommended), the serrations will hold the track a lot better. At any rate, the T-Track goes into the two slots to provide a clamping surfact not only for the fence, but for an almost endless variety of clamps as well. The sacrifical insert is a 3/8" thick piece of particle board, masonite, or other material that will serve as a drill pit. If you have a hard time finding 3/8" material, you can buy replacement drill pads for the commercially made drill tables. Note also the cutout on the right rear of the table. This is for the drill press table elevator crank. The dimensions for this cutout are only approximate as the dimensions for your drill press may differ.

The table simply mounts with two 5/16" dia carriage bolts that protrude through the table, then through slots in the factory drill press table. The table is then secured with two large thumbscrews. This allows the drill table to be rapidly removed from the drill press as conditions warrant.

The completed drill table, along with the Incra Track fence system with the Incra Shop Stop, drill pad, and table mounting bolts. This is the finished project ready for mounting on the drill press.

A close up of the Incra Shop Stop reveals several adjustment mechanisms. The trick is to mesh the Shop Stop to a nearby set of alignment teeth, then use one of the adjustments to place the stop so that the first hole drilled into your project is exactly in the correct spot. Then, subsequent holes are aligned by meshing the Shop Stop into a new set of alignment teeth on the rack without disturbing the adjustments. So in a sense, the adjustments "zero" out the Shop Stop.

The Incra Track system is quite versatile. You can use one or two Shop Stops (one on each side of the drill press) if you wish, as there is literally no limit to the different configuration you can make with this system. And if you combine the fence with a commercial table, such as Woodpecker's WPDPPACK1, the possibilities are almost endless. If you noticed the vacuum hose attachment in the first photo, it can be ordered from PeachTree Woodworking Supply, item #351.

Example on using this system to drill holes


References
INCRA Track.
Incra Shop Stop.
Woodpecker's Drill Press Table.
INCRA Track Instruction Manual.
INCRA Shop Stop.
Hartville Tool T-Track.
Hartville Tool Moby Clamp.
Hartville Tool Drill Press Table.
Rockwell 1" Dia Nuts.
Rockler Drill Press Table.
PeachTree Woodworking Drill Press Table and Dust Collection System.

Boat-Project.Com example on using this system to drill holes

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