: How was I ever going to sand this huge concave?

I do all of my flat, convex & concave sanding now with soft pads I cut from Walmarts 1/2" x 20" x 72" blue polyolefin camping pad for my 5" ROS. Cost less then $6. I cut a 5" pad out and spray adheasive on both the pad and ROS and stick them together whey dry. Then I spray the pad, let dry and slap on a sticky sanding disk. Once in a while I tear the pad trying to get the used disk off but if it's not torn too badly I just put anothr disk on, but if it's too bad I just cut out another pad. I don't use the hook and loops anymore so I don't worry about messing them up with the spray. I had a picture but lost it somewhere. It works well for me. This polyolefin material may have some other uses for kayaks that I will try later on and report if it works out. I submerged a square foot x 1/2" of this under water for 7 days and it retained only an ounce of water which was completely gone in 7 days when taken out of the water. I also smbmerged a square foot x 1/2" of the Dupont blue building insulation foam for 7 days and it absorbed less then 1/2 oz of water that was completely gone in one day when I took it out of the water. I had a few slits from a utility knife in this test piece that water got into, so water may not penitrate this foam at all. I am going to shape this material and use it for floation in the bow and stern of the yak I am building now.

John