The picture frame piece is supported by a block ... To use the jig, clamp it to the drill press table and the workpiece to the jig. Draw an “X” across the corners to find the exact center ...

Well you wouldn’t, unless you’ve built an intricate jig for assembling sunglasses frames like [Mosevic] has done. Boiled down, this is like making parts out of carbon fiber, except you swap in ...