I would be tempted to hard mount the drills / spindles, and move the work up to the drills. this is probably lighter and easier to move.
Once you get this far, you might as well go the next step and just drill all 20 ft in one plunge. It would be tempting to spray some water on the bit while drilling to reduce melting. It might even be possible to just punch a hole like that.
As mentioned earlier, if the drill motors are mounted on an adjustable mounting arrangement, you could deal with the different pitch easier. |