How to Make Door Shims

Shims are triangular wedges of wood used to position framing timbers, doors, cabinets and gates for accurate installation. When you're installing a pre-hung door, the door jamb is set in place. A carpenter's level ensures that the rails of the jamb are horizontal and the stiles are perpendicular in two planes. The shims are hammered between the doorjamb and framing studs as a place holder while you screw the jamb to the studs and transom board. Commercially manufactured studs are inexpensive, but you can quickly make your own, using a miter saw.

Things You'll Need

• Miter saw
• 2-by-8-inch milled lumber

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Instructions

1. • 1

     Set the miter saw to make a perpendicular cut and lock the blade in place. Lay the plank on the saw table with its 8-inch surfaces horizontal. Push the plank against the guide fence. Trim off the end of the plank so you have a clean-cut edge on the perpendicular surface of the shim.

   • 2

     Unlock the blade and rotate it to make 10- to 15-degree cuts. The precise angle is unimportant. Slide the trimmed plank on the saw table so the cut forms a sharp point on one end of the shim. Hold the plank against the guide fence and cut the plank to complete the first shim.

   • 3

     Rotate the blade to make perpendicular cuts. Line up the plank so the cutting line can create a shim with a sharp point on one end. Hold the plank against the guide fence, then cut the second shim. Continue rotating the blade from perpendicular to a 10- to 15-degree angle after each cut. The second cut from the previous shim forms the first edge of the next shim.