Here is a tray I made for my fiancée for Valentine's day. The tray is made out of padauk. I cut the inside of the tray in several passes using my homemade CNC router with a 1/2 inch core box bit. This leaves a nice radius on the bottom that adds some strength to the sides. The sides are approximately 1/8" thick. To make the bottom flat, the final pass only stepped over by about 10% of the bit diameter. This left very tiny grooves in the tray which I was able to remove by sanding. After sanding the inside and outside of the tray I finished it using a semi-gloss acrylic finish.