Previously we completed the main stage platform, and filled with sand. Next I built another box in front of the "sand box", with a 1/2" gap, as I didn't want to front part of the stage with sand, so needed to decouple it from sandbox. The arcs will be built in front of the middle box.
Well, after building the middle box, we decided the stage was going to stick out to much. Hence I needed to make the middle box about 6 inches narrower..... So how does one take apart a framed 2x12 box that I went overkill on with my framing nailer???? My neighbor came up with an excellent idea THAT WORKED - I used my hydraulic floor jack!
Can you say overill on the nails?? I just love the framing gun!
For the radius of the stage, we tried several methods for drawing arcs. String didn't work. Measuring points and connecting didn't work. So the best way I found was with a makeshift compass:
Here you can see 4 arcs - one for each step, and one for the 2 overhangs
I then drew in the framing members on the paper template, and framed on top of it. This helped me mark the framing member angles that the step face will attach to. Once framing was done, we removed the paper template, put down more roofing felt, and wrapped 1/4" plywood on the faces:
We then filled with pink unfaced insulation, and glued and screwed on the plywood. The bottom step has 1 layer of 3/4" plywood. The top step has 2 layers, and roofing felt in between. Top and bottom of steps were beveled with router - 2" overhang.
Thanks to all for input on this great design, as well as carboranadum for many answered questions!