They are laminated strips of 1/16" pieces. It can't be made like today's standard cove molding, cut from a single piece of wood and installed at a 45 degree angle, they have to be stacked molding pieces. I use two form pieces, an inside radius and an outside radius, covered with wax paper. This is one set.
Each successive piece has a larger radius, of course, so the outside radius of the first piece is the inside radius of the second piece, etc. Lots of forms, lots of gluing up. I make the strips about 1/2" wider than the finished size, giving myself some wiggle room, because after they are glued up, I then joint one edge. I have to be careful to check it every couple of passes to keep the jointed edge at 90 degrees to the face, because it is easy to take off too much at the ends and not enough in the middle as I pass the curve over the jointer knives. That's why it is 1/2" wider than needed, so that I can adjust if I go out of 90 degrees.
Once I have a good edge, then I rip it on the table saw to exact width. Yes, it takes a great deal of focus and concentration to do this without damaging either it or myself. Then I cut the profiles on the router table using the bits in the photo.
Next, I will cut straight pieces to match the profiles, then I will join them to the curved pieces using mortise and tenon joints, so each profile will be a single piece that is straight for about 8', then curves around the face frame and dead ends into the wall. For the first two pieces, I will draw them tight to the curve of the face frame using several screws inserted from the back side of the FF into both profiles. The last profile, the smallest, should be able to be secured using brads.
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