Instructions to laying out the Octagon
LINK TO WIKIMEDIA.ORG
http://commons.wikimedia.org/wiki/File:Regular_Octagon_Inscribed_in_a_Circle.gif...
My son-in-law bought this plaque at the Daytona Car show in Florida 11/25/2011. He waned me to make a frame for it.
I put rope lighting inside to illuminate the blue lexan.
The lexan is clear but I left the blue protective sheet it gave it a nice color contrast. The frame is 27" in diameter and the Plaque is 23" in diameter. I added a some wood to the back 1" x 1" a to attach the rope lighting. Go to Wikipida and search... Regular Octagon Inscribed in a Circle.gif
Note:
In mitering the pieces that form the angles of an octagon, the miter saw should be set at 22-1/2 degrees.