I was affraid of that, but thought the initial set up time would be shortened. We use optical benches at work to both initial (ballpark)and final configurations on some devices and they work quite well. I would think that a barrel would fall into this same approach..The theory should be the same........Oh well I'll keep thinking......Thanks,

Tinker,
i read the article twice to fully understand what the dynamics are.....an interesting project to test out...............and I now understand that initial set up is the most that one can expect.
I do like the witchcraft comment.........or black art as it is know in the aerospace industry.

I wonder what thr routine is for a drilling?
TC