Table saws are ideally suited for ripping lumber—long cuts parallel to the grain of the wood. However, one common accessory that is typically included with your table saw, known as a miter gauge, can make the table saw just as useful for making cross-cuts perpendicular to the grain of the wood at various angles, from 90-degree perpendicular cuts to miters of almost any angle. Since a table saw's blade can also be set for angles up to 45-degrees, the miter gauge allows your saw to make many of the compound cuts that are normally reserved for a compound miter saw or radial-arm saw.
Most table saws come with miter gauges, but there are also specialized and highly precise after-market miter gauges you can buy. A good miter gauge is a highly precise piece of equipment that may cost several hundred dollars. Top-quality miter gauges are precise down to fractions of a degree.
How a Miter Gauge Works
A miter gauge consists of a long thin metal guide that rides in the miter slot in the table of your saw. Attached to this guide is a half-moon shaped head that pivots on its connection point to the guide. A locking mechanism allows this pivoting section to be locked into any angle, from -45 degrees to +45 degrees). When a workpiece is placed against the fence of the gauge and the entire assembly (miter gauge and board) is slid forward across the saw blade, the workpiece is cut at the precise angle you called for. Some miter gauges have "positive stops" that allow the gauge to be quickly set at the most commonly used angles (such as 90-, 45-, 30-, and 22 1/2-degrees).
Making Square Cross-Cuts with a Miter Gauge
As you learn to use a table saw miter gauge, the easiest cut to learn is a square cross-cut, where the miter gauge is set to 90 degrees based on the angle markings on the gauge, and the end of the board is cut square.
Although the angle settings on miter gauges are designed to be as accurate as possible, often they can be one or more degrees out of kilter. To check the accuracy of your gauge:
- Set the gauge to 90 degrees (or 0 degrees, depending on how your gauge is marked) markings), for a square cut that is perfectly perpendicular to the miter slot on your table saw).
- Unplug your table saw's electrical cord and raise the blade as high as it will go.
- Slide the gauge forward until it is in line with the front edge of the exposed, stationary saw blade (do not attempt this without first disconnecting the saw from the power source).
- Place one square edge of a 6-inch combination square against the saw blade, and the corresponding edge of the square against the flat, forward edge of the miter gauge. If the square aligns perfectly with both the blade and the gauge, then your gauge's settings are accurate. If there are any gaps between the square and either the blade or the gauge, adjust the angle of the gauge until they align perfectly, and tighten the locking mechanism.
To make a cross-cut:
- Slide the miter gauge backwards (toward your body) to the front edge of the saw table, and place a board against the flat edge of the gauge.
- Make a pencil mark on the wood where you want to make the cross-cut, and align that mark with the saw blade (while keeping the board flat against the miter gauge).
- Plug in and turn on the saw, then slide the miter gauge—with the board held securely against the head of the gauge—forward and past the saw blade, completing the cross-cut.
- When the cut is completed, ease the board along the gauge and away from the blade and slide the whole assembly back to the starting position before turning off the saw motor.
As with any operation with a table saw, always keep your hands well away from the table saw's blade.
Making Angled Cross-Cuts with a Miter Gauge
Angled cross-cuts are similar to square cuts, except that the miter gauge is set to an angle of up to 45 degrees before sliding the gauge and corresponding wood piece toward the blade to make the cut. When making an angled cut using the miter gauge, move the gauge a little bit slower than you did making a square cut, as the gauge's movement may tend to slide the board out of position as you move it across the blade. A small woodworking clamp can be used to secure the board to the gauge as you make the cut.
Compound cuts, featuring both miter and bevel angles, can be completed by setting both the angle of the miter gauge and the bevel of the saw blade to the desired angles before sliding the gauge forward across the saw blade.
Adapting a Miter Gauge
When cutting longer boards (of up to 4 feet in length), you may wish to secure a sacrificial strip of wood to the face of your miter gauge to provide added stability to the board being cut. Most miter gauges have a matching set of holes in the back through which you can drive a wood screw to secure the sacrificial board to the flat face of the miter gauge. Some high-quality miter gauges come with an extra-long wood facing for exactly this reason.
Additionally, there are jigs that can be attached to a miter gauge to make specialty cuts. One such example is a box joint jig for making perfectly-matched box joints (or finger joints) using your table saw and a stacked dado blade set.
- Cross-cuts on boards longer than 4 feet should probably not be attempted using a table saw and a miter gauge. Not only are they too difficult to align accurately, but the saw table is usually too small to accommodate such a board safely.
- When making any kind of cross-cut with your miter gauge, do not use your table saw's fence in conjunction with the miter gauge. While it might seem logical to align the fence with the blade at the desired cut distance, then slide the butt end of the board against the fence while making the cut, this creates a high likelihood of the board binding against the fence and kicking back violently. Instead, either remove the fence or slide it well out of the way before attempting any cross-cuts (square or angled) using the miter gauge.
- Last, but certainly not least, always wear protective safety gear, including safety glasses, hearing protection, and appropriate clothing, when using a table saw or any power tool.