Keyne,
The problem with that design was that I couldn't ever get the bearings to set straight on the rail. The lock washers cause the bearings to get cocked when the nuts were tightened down. I also designed the gear rack to be on the outside so there won't be any way to stop the gantry from lifting off.
Gerry,
Your gantry skews as well?
Adding another motor to the opposite side is out of the question. I don't want the added headache/cost/etc. (or at least for the moment let me dream that is won't come to that)
I have some pillow blocks with roughly 4 feet of linear rail that I'm going to try out tomorrow. I would think if the gantry does this on only a 1 foot section, vising the rail down and the blocks to the gantry will be able to tell me.
If that doesn't work next thing will be to fire off some emails to people with large machines and see how they eliminate it. Or I wonder if it's possible to "dial" it out on software side.
-Matt |