Bill, I have used that thick Krylon clear several times. This is what I do:
I use shellac as a sanding sealer at 600, and resand at 600, then through the grits and MM. At this point I take the barrels out of the mandrel, and put them on a stick (well, it is kind of a wood mandrel, 1/4" dowel) so I can spray them, off the lathe. I keep the barrels away from each other. I spray a heavy coat, let dry a couple hours, another coat, and next day another coat.
The finish at this point is glossy, but uneven. Sure does not look like glass !
I clean the ends of the barrels with some sandpaper to take off any surplus finish. Then they go back on the mandrel and on the lathe. I then start with about 1200 paper, and level the finish. When it looks uniformly dull and flat, I go through the grits to 12,000 MM. At this point the result is like glass. Some TSW and I am done.
