Hi All,
I need some help. I am trying to construct a hollow square pyramid frustum using slabs. Top inside 1" x 1", outside 1.25" x 1.25". Bottom inside
4"x4" outside 4.25" x 4.25" The angle of the side to base is 60 degrees, the slabs are cut with the top and bottom parallel and the sides at ~65 degrees. In order to be square at the top and bottom, the adjacent sides aren't square to each other and there in lies my problem. I can't remember the way to calculate the bevel the edges of the sides so that when two side are assembled they are square when looked at from the bottom or top. I knew this trick years ago from making micro wave horns but I can't find my notes. All help appreciated, a pointer to a web sight with graphics and forumlas would be even better. Kent