Patent attributes
The invention relates to an improved miter box for guiding a handheld portable circular saw. The miter box facilitates several conventional workpiece trim cuts using a handheld portable circular saw, including 45 degree and 90 degree straightcuts, as well as 45 and 90 degree straightcuts with a 45 degree undercut. The invention includes an I-beam that is formed from a rigid base plate having opposing first and second base plate edges disposed along its elongated length. A first and second flange can be respectively attached to the opposing first and second base plate edges. Each of the flanges can include a pair of opposing support faces. One or more transverse guide members can extend either 45, 135, or 90 degrees from one support face of the first flange to another support face of the second flange. The transverse guide member(s) and the support faces provide a friction reduced medium by which the bottom of a handheld portable circular saw's shoe can glide with greater ease and stability.