Where? Google isn't as smart as you think. For a 19' span you would probably place the nails a couple inches in from each side to get a foot or two rise. I can see how you would do it by guessing, but I don't see anything that gives you the math.You can also google more info on the math behind the oval method such as oval height vs oval width = x distance between nails and x string length.
I see, miscommunication. If someone told me to build an "eyebrow" I would admit I have no idea what you're talking about.tyb525 said:It started as an ellipse, then I "cut off" the bottoms by several inches to get that shape. Originally I thought the HO wanted the ends to curve into the drywall posts like a true ellipse, but they wanted a defined corner like shown. It is not a standard arch but it does look like it at first, the radius gets sharper at the ends where an arch doesn't.
The biggest hassle was getting the flexible bead to form a smooth curve without waves or flat spots.