There's another possibility that you're not considering. The lead screw only has a problem with whip, if it's turning!
Keep it still!
I saw mention of a design on CCED, which basically turned the nut, rather than the screw. Of course, keeping backlash down was a concern, since there's a rotating mechanical linkage between the nut and the stepper, but the general tone on the list was that it was a workable solution.
You should be able to get away with a MUCH smaller screw, using a system like this.
-- Chuck Knight |