How do I make an octagon from a square piece of plywood 4 ft on a side?

Answer 1

mark 1 foot on each edge both ways across each corner. then draw a line across each of the corners. if this is done correctly you then cut the corners off
donkey is right , I thought abou what i wrote and that would make four sides seventeen and one eighth inches

Answer 2

It might help to have a 45 degree fast square. Aren't you lucky you have someone to do the calculations for you! Measure from each corner approximately 14 and 1/16" on each side. Mark these points, and draw lines using a straight edge or your fast square from point to point. When you trim off the corners, be sure the saw kerf lies just outside this line, not directly centered on it. This gives an octagon with about 19 7/8" each side.

Additional:
Russel is not correct. His method will not give you a regular octagon. In order for it to be regular, and the overall dimensions to be 48"x48" each side has to be approximately 19 7/8" long.

Answer 3

OK. Area = Length times width. As it's a square, length =width. Multiply 4 1/2 by 4 1/2 = 20 1/4 Area = 20 1/4 square feet. Hope this helps.

Answer 4

find the center point on all 4 sides. measure 2' out in each direction. do all 4 sides. draw lines from each 2' mark to the mark on the next side. then cut the corners off and your done.

Answer 5

This is the easiest way I know. It works everytime very accurately. Just insure that the first 45 degree angle is absolutely correct: http://bobhamswwing.com/Articles/Cutting%20an%20Octagon/Cutting%20out%20an%20Octagon.htm

Answer 6

lay it flat on a table and sculpt out the sides