How to Cut Base Moulding With a Miter Saw

A miter is a joint forming a bevel.There are several types of miter saws that allow you to bevel a cut for a more precise fit on a project such as cutting moulding. One type of miter saw is a simple box, which is effective except it allows for 90 or 45-degree angles only. A hand operated miter saw allows you to make delicate adjustments to the angle. It is sometimes necessary to adjust a cut to a piece of moulding if walls or doors are sagging or otherwise out of alignment.

How to Use a Miter Saw

• 1

  Find the exact angle needed for your moulding using a sliding T-bevel. A T-bevel is an adjustable gauge to transfer or set angles. Adjust the miter saw before cutting to the angle needed. Casings or door moulding is usually mitered at the top of the door on the corners. Crown moulding generally is installed at a 45-degree angle.

• 2

  If the floor or wall for the base moulding is at a different angle than what your miter saw can handle, adjust the miter saw by using a shim to get the angle needed. A shim is a piece of scrap wood the base moulding rests against to create a particular angle cut the miter saw is unable to make by adjustments. Move the shim away from the blade for smaller angles and closer to the blade for larger angles.

• 3

  Place a shim onto the portion of the miter saw furthest from the blade if the moulding measurement is at an odd angle. Place the moulding tight against the shim and the fence near the blade. Hold this position when making a cut.

• 4

  Trim the other piece of moulding and miter cut the same way. Place the blade slowly onto the wood to shave the moulding, which smooths the beveled edges. Both pieces of moulding need the same cut before they fit. The shim adjusts the angle of cuts rather than trying to adjust the angle of the miter saw.

• 5

  Cut a shim thick enough to place under the straight edge of a yardstick or combination square for casings or door moulding. Place the shim on the outside of the door moulding. The shim raises the outside edge of a door moulding before cutting the shim and then place shim under moulding on the miter saw and cut at a 45-degree angle.

• 6

  Trim the drywall around the door moulding back using a utility knife if needed so the moulding doesn't rock when set between the jamb and the drywall. Tilt the trim on the bed of the miter box to match the angle where the moulding rests against the wall. If the drywall is recessed, build it up by using a thin piece of material, such as jamb extensions or a piece of wood used to widen or increase the depth of a jamb, over the edge to bring it flush to the wall.

• 7

  Use the shim to lift the outside of the moulding and cut the miter, or bevel of the moulding at a 45-degree angle on the miter saw. Cut both sides the same way by shimming and cutting.

• 8

  Tilt the trim on the bed of the miter saw matching the angle that fits against the wall. Use this technique if the baseboard moulding does not fit flush against the wall. Cut a bevel in the baseboard by setting the miter saw at a 45-degree angle.

• 9

  Turn the baseboard upside down in the miter box and adjust the miter saw to a 15-degree angle. Saw straight down the beveled cut stopping at the top of the moulding or the baseboard profile.

• 10

  Angle a coping saw, which is a saw used to cut intricate cutouts or curves in carpentry; to about 30-degrees and create a back bevel for a better fit. Coping the inside corners of a baseboard is the easiest method to fit baseboards to the wall because coping cuts do not open with humidity or when nailed.