I am delivering a drop soffit arch for a waterfall today. For those of you who may not know what a drop soffit is, it is the underside of any architectural element. Here is a Wikipedia link - https://en.wikipedia.org/wiki/Soffit
The goal on this project is to have a curved section of wall "drop" out of the ceiling 20" and for 2 perfectly concetric circles, comprised of 2 large half round arches. In the center of the smaller circle will be a waterfall. This project will also include the added challenge of a facing ring to connect to two pieces at the bottom.
It should be installed in the next couple of days. I will get a picture after it is installed and after it has been trimmed out.