To use a miter saw, you measure and mark your board, set it flat against the fence, line the blade up with your mark, and make the cut. [1] [2] That same routine works for every cut the saw does best: square crosscuts across a board, miters that angle the cut left or right, and bevels that tilt the blade for a slanted edge. For more detail, see When to Use a Miter Saw Instead of a Circular Saw.
The saw is built for cutting boards to length and angle. For ripping a board along its length or breaking down plywood sheets, a table saw is the better tool.
Before your first cut, set the saw on a flat, level surface such as a table, then plug it in or attach a battery. [3] You’ll also find the habits that keep your cuts accurate and your hands clear of the blade, plus the mistakes beginners make most often.
How should you set up the saw before cutting?
Before your first cut, put the saw on a solid, level base, power it up and fit a blade that matches the job. Ten minutes of setup here saves you from wobbly, splintered or out-of-square cuts later.
Give the saw a flat, level base
Set the saw on a flat, level surface, and a sturdy table works fine. [3] If the saw rocks or tilts, the blade won’t meet the board at the angle you set, and a 45-degree cut can come out a degree or two off. A workbench, a dedicated miter saw stand or a solid folding table all work. A sawhorse with a loose sheet of plywood on top usually doesn’t.
Bolt or clamp the saw down if its base has holes for it. That keeps it from creeping across the table as you push boards against the fence.
Connect the power
Next, plug in the saw or, on a cordless model, attach the battery. [3] Run the cord so it hangs off the back or side of the table, away from where your boards and hands move. If you use an extension cord, lay it where you won’t trip over it while you’re carrying long stock.
Choose a blade for the cut you’re making
The more teeth a blade has, the smoother it cuts. [4] For construction cuts, such as framing lumber or deck boards, use a blade with more than 50 teeth. [4] For fine work like moulding and trim, use a blade with more than 90 teeth. [4]
The higher tooth count leaves cleaner edges with less splintering, which matters on trim, where every cut shows. For rough 2x4s that end up behind drywall, a lower-tooth blade is plenty and cuts faster. Many DIYers keep one of each and swap them depending on the project.
Support long boards at table height
Long boards need support at the same height as the saw table. An 8-foot board hanging off one side will sag and pull away from the fence, which throws off your cut and can pinch the blade.
You can use roller stands, a miter saw stand with extension arms, or a stack of scrap lumber shimmed to the right height. Lay a straightedge from the saw table onto the support: it should rest flat across both.
How do you make a straight crosscut?
A straight crosscut takes four moves: mark the board, set it against the fence, cut with the blade at full speed, and check the result before you cut the rest. Here is the sequence for a square cut, such as trimming a 2×4 to length for a shelf frame.
Measure and mark a line across the stock you want to cut. [1] Use a tape measure and a pencil line that is easy to see, and draw it across the full width of the board so you can line up the blade at any point. [2] A small X on the scrap side keeps you from cutting the wrong end.
Place the board flat on the saw table and press it against the fence. [2] Lower the blade without power to see where it meets your mark, then slide the board until the blade sits on the waste side of the line, next to the X. The blade removes a strip of wood about as wide as its teeth, so cutting right on the line makes your keeper piece that much short.
Turn the saw on and let the blade come up to full speed before it touches the wood. Then lower the head through the board in one smooth, steady stroke. Pushing too fast can bog down the blade and leave a rough edge.
Keep your hands out of the blade’s path the whole time. Hold the board with your hand well to the side of the cut line, and wear eye protection, since chips fly off the blade. When the cut is done, release the trigger and let the blade stop completely before you raise the head. Lifting a spinning blade can catch the cut-off piece and throw it.
Check the first cut for accuracy before you cut more pieces. [5] Hold a square against the cut end and the board’s edge, and measure the length against your plan. If you need four matching pieces, use the first one as a gauge for the others, and the stack now lines up flush at both ends.
How do you cut miters and bevels?
Cutting a miter or bevel means setting the saw to an angle, locking it, and proving the setting on scrap before you cut your real board. A miter is an angle across the face of the board, set by swinging the table left or right. A bevel is an angle through the thickness, set by tilting the saw head.
Setting and testing the angle
Unlock the miter table. Most saws have a handle or knob at the front of the table that releases it so it can swivel.
Swing the table until the pointer lines up with the angle you want on the scale, such as 45 degrees for a picture frame corner. Many saws have detents (small notches) at common angles that the table clicks into.
Lock the table so it can’t drift during the cut.
For a bevel, unlock the bevel lock, usually at the back of the saw, and tilt the head toward the angle you need on the bevel scale.
Lock the head in place. If it isn’t locked, it can sag partway through the cut and leave an uneven edge.
Make a test cut on a piece of scrap the same thickness as your project board. Check the result before you cut the real piece [5]. For a 45-degree miter, cut two scrap pieces and hold them together: they should form a tight 90-degree corner with no gap at the inside or outside edge.
If the corner gaps, nudge the angle slightly, lock it again, and cut new scrap until the joint closes.
Cut your marked workpiece using the same positioning you used for a straight cut.
Compound cuts
A compound cut combines a miter and a bevel in one pass, so you set and lock both the table and the head before cutting. Crown moulding is the classic example, because it sits at an angle between the wall and ceiling and its corners need both settings at once.
The extra setting makes the scrap test even more useful here. With two angles in play, a small error in either one shows up as a gap at the corner, so cut a pair of test pieces from leftover moulding and fit them together before you cut the full lengths.
What keeps your cuts accurate and your hands safe?
Accurate, safe miter saw cuts come from a few habits you repeat on every board. Each one keeps the wood from moving and keeps your hands out of the blade’s path.
Hold the board flat and tight to the fence
A board that rocks or drifts away from the fence gives you a cut that is off square, even when the saw is set perfectly. Lay the stock flat on the saw table and press it firmly against the fence before the blade touches it, so it can’t shift mid-cut. [2]
A bowed or cupped board needs a little more care. Turn it so it sits steady, with the hollow side facing down or toward the fence, and you avoid the board pinching or jumping as the blade cuts through it.
Cut on the waste side of your line
The blade removes a strip of wood about as wide as its teeth, called the kerf. If you center the blade on your pencil mark, the piece you keep loses half a kerf and comes up short.
Line the blade up so it lands just beside the mark, on the scrap side. Say you need a 24-inch shelf. Put the blade on the offcut side of the 24-inch line, and the full 24 inches stays on your keeper piece.
Never cut freehand or hold short pieces near the blade
Every cut needs the board resting on the table and against the fence. Holding a piece up in the air or angling it by hand lets the blade grab it and throw it.
Short offcuts are where hands get closest to the blade. If a piece is too small to hold with your hand well clear of the blade path, cut it from a longer board instead. Clamp the stock when you can, so your hands stay out of the way.
Let the blade spin down fully before lifting
When you finish the cut, release the trigger and keep the head down until the blade stops turning. A blade that is still spinning as it rises can catch the offcut and fling it, or chip the edge you just cut.
Once the blade has stopped, raise the head, then reach in to move the pieces.
Common beginner mistakes with a miter saw
Most first-time problems with a miter saw come from three habits: the wrong blade for the job, skipping a trial cut on angles, and a shaky work surface. Each one is easy to fix once you know what it looks like.
Cutting trim with a coarse blade
A blade with too few teeth leaves ragged, splintered edges on trim, called tear-out. On a painted baseboard or a stained window casing, those chipped fibers show right at the joint, and you can’t sand them away without rounding the edge.
Tooth count is the fix. A blade with more than 50 teeth handles construction cuts, but fine work such as moulding calls for a blade with more than 90 teeth. [4] In practice, the blade that came with your saw is often fine for framing lumber or deck boards, then you swap to a finer blade before you cut crown or casing.
Skipping the test cut on angled work
An angle that looks right on the saw’s scale can still be off by a hair, and on a miter joint that error doubles. Two pieces each cut half a degree off leave a visible gap at the corner of a picture frame or door trim.
The habit that prevents this is cheap: cut a scrap of the same stock first and fit the two pieces together. If the corner opens at the outside or inside, nudge the setting and cut another scrap. Save your good piece, especially a long length of trim, for when the scraps close tight.
Working on an unlevel or wobbly surface
The saw needs a flat, level surface, such as a table. [3] If the saw rocks or the stand flexes, the board can shift as the blade enters, and your square cut comes out slightly angled.
A few signs point to this problem:
The saw moves or rocks when you press down on the handle.
A long board tips the saw toward its unsupported end.
Cuts that should be square are inconsistent from one piece to the next.
Set a wobbly stand on firmer ground, shim the legs, or move the saw to a sturdy workbench. A solid base makes every other setting on the saw more reliable.
Your first projects with a miter saw
Every good miter saw cut comes from the same short routine: set the saw up on a level surface, measure and mark your line, hold the board flat against the fence, make the cut, then check it before you cut the next piece. [2] [5] Once that order is a habit, square cuts, miters and bevels all follow the same pattern.
Your next step is to grab a few offcuts of 1×4 or 2×4 and practice on them before you touch trim or furniture parts. Cut a square end, then a 45-degree miter, and fit two mitered pieces together into a corner. When those scrap corners close tight, you’re ready for baseboard, a picture frame or a simple shelf.
