Classic (Sells Mendel style) Bar Clamp, in two part harmony. (Q88672)

When rebuilding my lasercut wooden printer, I decided that one of the things that could use improvement over the Prusa design was the bar clamps. Now that the Y carriage is non-adjustable, the position of the Y axis smooth rods relative to the frame is critical, and the Prusa style bar clamps don't do a good job of enforcing the spacing between the two rods. I looked at the original (Sells mendel) Bar clamps, and decided that with 3 parts, they were more complicated than I liked, so I designed these as a replacement. Revisions:     Reduced the slop on the nut traps from .5 to .25 - apparently my .35 nozzle doesn't shrink holes as much as the .5 nozzle did.