How to Cut Off Door Shims

Wood shims have many uses, including easing a door jamb into a level and plumb position before it is permanently fastened. Shims are long, slender wedges of lightweight, brittle wood that fill unwanted gaps. The long, gradual slope of the wedge helps you fill the gaps precisely, but the length of a shim leaves a lot of excess material for you to cut. Cutting door shims is a simple process that requires only one tool and a steady hand.

Things You'll Need

• Utility or razor knife

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Instructions

1. • 1

     Fasten a new blade to a utility or razor knife.

   • 2

     Press the tip of the blade against the top of the shim at the edge of the door jamb. Angle the tip of the blade in toward the jamb, instead of holding it straight, to undercut the shims behind the jamb.

   • 3

     Drag the blade slowly down the shim with firm, steady pressure, scoring it from top to bottom.

   • 4

     Push against the free end of the shim to snap it at the scored line.

   • 5

     Trim off any splinters, if necessary.