I've got a job to re-do a new kitchen. The owner doesn't like some of the previous work and design. One of the things I'm considering doing is adding a Tudor arch (his house is Tudor and he wants the theme carried over into the kitchen cabinets) over the stove/oven area. The problem I'm having is how to design the arch with the appropriate proportions. I know that Tudor arches have 4 radii, 2 on each side of the arch. What I can't figure out is where the radii center points are placed to get the correct relationships. I've tried trial and error, but got all errors. Right now I'm in the CAD stage. Anybody know how to do this?
(Architectural Woodworking Forum)
From contributor B:
I played with this a bit this morning. I hadn't heard the term "Tudor arch," so did some Google searching. Found some interesting info. I didn't find a formula, though. I did find a definition that stated 4 radii, as you said.
To me, though, the pictures of Tudor arches look more like top pointed ellipticals. So, I drew a 48" x 12" elliptical in AutoCAD. Then I took a line straight off the top center vertically upward for 4". I then drew a line from the top of that 4" line to the tangent point on the ellipse to the left and right. Trimming away the top center of the original ellipse left a pretty good looking Tudor arch.
Then to see if I could get the straight lines from the top point changed to curves, I simply drew a 3 point arc from top center to a point about 1" to 2" out from the center of the straight line, and then down to a visually tangent point on the original elliptical side tight curve. For some reason using a "tangent" snap here didn't generate the two curves as tangent to each other. This process seemed to give me the correct proportions.