Kenneth Michael Guitars est.1978
"X" Brace overlap joint cutting  tool
The joint angle is set by aligning the guide
to the “X” brace layout. I set a piece of 1
by 2 on one brace outline so the tool can
be butted against something solid. Once
set the wing nut gets tightened. Since the
angles are complimentary you only need
to do this once.
The tool allows you to line up your cut
mark and secure the brace with a small
clamp. The razor saw is accurately
positioned along the angle gage, which
aids keeping the blade perpendicular.  
The tool is made of ¼ inch ply. Each
leg is about 2X10 inches. The lower
leg has two risers epoxied to the edges
they need to be about 11/16” tall.
The photo of the bottom of the lower
leg reveals the two cross stabilizers.
You can also see that the ¼” carriage
bolt is glued in place.
The upper leg has  two pieces of ¼ “
material glued along the edge to act as
a stabilizer for the razor saw.
A riser 11/16” tall needs to be glued to
the bottom of the upper leg to keep the
whole unit level with the work surface.
None of the dimensions are critical, the idea is to be able to move and clamp the
braces along the bottom leg using the upper leg to pin point the cut location.  Note
that I am left handed --- so perhaps some would find the fixture easier to use if it
were reversed?  In any event I am now able to go from layout to layout and cut
perfect squeaky tight “X” brace lap joints in a minute or two.