Cutting the pie panels
First cut
After making sure I had a successful fiberglass inner dome, it was time to begin cutting the top “pie panels.” I used several techniques to figure out the template for these. First I had to find the exact center of the dome, where I would drill a hole and mount a bolt to use as a pivot for tracing my circles. The lines/grooves from the production of the dome were not completely sanded out, so I had a good idea of the ballpark it had to be in, then I put the end of a string or tape measure at the point I picked and measured to the bottom of the dome at several different points.
To get the measurements, I used a combination of two different dome layout “blueprints” I got from the R2 builders’ yahoo group. I remember them being difficult to track down, since there are so many different dome profiles and a pattern that works for one won’t work for another. As shown in the “first cut” image above, I drew the lines several times before I was satisfied. In the end, I just had to suck it up and go with what looked right to me. That’s one of the things I love about the R2 builders’ community: no two droids are exactly alike, and the only ones who notice that your panels are off are other builders (and they understand).
Pie panels cut
I used a dremel with cut-off wheels to get the cuts started, then I used a jig saw to cut all the “latitude” lines. If I had it all to do over, I would have mounted some felt or something to the baseplate of the jig saw since it left scratches that I later had to sand out. I used the dremel only for the “longitude” lines – I don’t remember my reasoning. One important thing I did was to number all the panels clockwise, and write the number on the back of each of them (I also marked the dome in pencil above the first panel). Since I didn’t make perfect cuts, each panel was unique and fit best in its orginal spot. I screwed up later and had to switch two panels around, and it sucked having to make it fit.
Once all the panels were cut, I cleaned up all the lines with diamond files from American Science and Surplus and sandpaper. I cannot overstate how satisfied getting the dome to this point made me. It was finally starting to look recognizeably like R2D2.