Custom Miter Box for large urethane decorative molding

I created a three sided box by gluing and nailing 3/4 pine
with triangle braces to ensure that it was square.  

Using a True Angle finder I marked off a
right and left 45* and a 0* in the center. These
lines then were extended down both sides of the
case using a framing square to ensure they were
perpendicular to the top.  Using a corded circular
saw, I made bevel cuts along these line with an
edge guide.

Since the 26" saw didn't allow enough cutting
distance within the miters, I installed some 3/4
pine cutting guides set on top along the miters
and set to the kerf of the hand saw to hold it tight.

The crown was set in place in the miter box at the
proper angle and held in place with some clamps.  I
scribed a line along the top and bottom to allow for
the same positioning for future cuts.

Just a look at the detail of this 14" crown
from Chemcrest.  ($30 a foot !!)

Also a look at the distance of the spring angle.

With the crown held in position, a slow and
accurate cut was made.

The result was an outside corner self return.

Now, an inside corner cut.

A little gold touch up paint and all set.