I recently built a bookcase and wanted to spray lacquer on both sides of the shelves. I could have set the shelves on nailpoints, but I wanted to keep the fresh finish absolutely untouched. So, I came up with a touchless method.
Fasten a frame of 2x2s, spread 1" wider than the length of the shelves, to a pair of sawhorses, as shown at top. Into the center of one end of each shelf, drill a shallow hole and drive a 2-1/2" deck screw into the hole, leaving about 1-3/4" of the screw sticking out. The same way, put two screws into the other end of each shelf.
To finish the shelves, lay them across the frame, resting them on the screws. When one side is finished, grab the shelf by the two screws and flip it over, rotating it on the single screw on the other end. If your frame won't hold all of your shelves, lean the finished shelves against a wall -- two-screws down -- to dry thoroughly.
--Kevin Bevins, Summerville, S.C.