I am planning to make some large arches of varying sizes (The biggest one is about 14 feet wide and 2 feet deep).
I am looking at the following options:
1) Make a template using 3/4" plywood (One sheets ripped and then joined together along the long sided for the desired 14' length). Use the convex template to cut other arches using similar sized plywood sheets and using a saber saw and a router.
I think that this is the approach most of the builders seem to take when I looked at the houses under construction in our neighborhood (not sure if they use router). I think that it will work fine except I think that this approach is extremely wasteful of plywood. Once I cut an arch, the convex leftover is simply waste since I cannot think of using it anywhere else. Is there any way to reuse the convex part for another arch?
2) Make a template as described in 1 above but then use the template to shape a curf-cut 14' long 2/4 into the arch in place supported by another 2X4s nailed in the ceiling at appropriate locations? Has anyone tried to make an arch out of curf-bent 2X4 or 2X6 that are supported by other structural members>
3) Any other thoughts?