I will need to make a few large circle cuts in building the wings. An access hole with a diameter of 5.25" must be cut in the tank root rib. Also, to modify the left tank for inverted flight the fuel level sensor must be relocated to the baffle in the second bay outboard from the root. This requires a 1.5" hole be cut through the baffle. I could probably use a standard hole saw for the baffle but a fly or circle cutter is required for the tank ribs. I was able to find the fly cutter shown below at a local tool supply house.
I have been looking for a 1/2" arbor to mount my large scotchbrite wheel on the drill press but have been unsuccessful. I finally decided to just make one from 1/2" threaded steel rod, some washers and a couple nuts. It works fine. To date, I have only used the smaller scotchbrite wheels but the larger one should be handier for some tasks. My smaller wheels are seriously worn and will soon require replacement. I wish they weren't quite so expensive.
