How to Set Up a Compound Miter Saw

We’ll test the saw by making cuts and checking the results. You need to have a perfectly straight edge on the test pieces. It’s best if you’ve run the edge over a jointer. You need three sets of pieces. One that is as wide as the maximum thickness capacity of your saw. Another that is as wide as the maximum cross cut capacity of your saw. And a final set that is as wide as the 45-degree miter capacity of your saw. You’ll also need a good quality square.

Position a piece vertically against the fence with the jointed edge down on the saw table. Cut one end and mark the end. Repeat the process with a second piece. Keeping the jointed edges down on the table flip one piece end for end and bring the freshly cut ends together. Be sure you’re keeping both jointed edges down on the table. Check how the ends meet. If they meet perfectly your saw is fine. If there’s a gap at the top or bottom of the cut you’ll need to check your owner’s manual and adjust the saw.

Hold the material flat on the saw table with the jointed edge against the fence. Make a cross cut in each of the two boards and mark the cut ends. Flip one of the pieces and, with the jointed edges against the fence, check how the freshly cut ends meet. Check your owner’s manual and adjust your saw as needed.

Set your saw to make a 45-degree cut. Cut both pieces with the jointed edges against the fence. Hold the two miters together and position the square at the inside corner formed by the two pieces. If the miters are accurate the square will snugly fit against both edges. If it doesn’t, you’ll need to check your owner’s manual and adjust the saw accordingly.