I use a 1 5/8" metallic hole saw on my drill press. I already had jigs made up for various board sizes. I center punch the lens board, then start the pilot hole, and use 3-in-1 oil to lube the cut.

The hole is just a bit undersized, so I use a portable sanding drum on a drill to enlarge and smooth the edges of the hole, test fitting every second pass.

Works right every time.