I think we are getting tangled up in terminology. To simplify our discussion let's consider only the bottom most axis, whether you call that X or Y.
Even with the lead screw exactly in the center the machine will try to torque the slide bearings one way or the other. To counteract that force the distance between the bearings on the same rail (1 to 2) needs to be bigger.
Lets assume that the rails are 30" apart (1 to 3) then the lead screw is 15" from either rail. What was suggested to me is that the distance from fron to back (1 to 2) of the bearing arrangement should be 7.5" or more.
The height of the gantry bridge (3 to 4) will have a similar effect.
If what I'm saying still does not gell then you probably should take the subject up with Igus tech staff. They will be glad to discuss it with you on the phone. |