Hi njhussey,

Sorry to jump in with a sales pitch (!), but as an upgrade could I interest you in some bits to replace your pipe and skate bearings:
http://www.mycncuk.com/forums/showth...l-and-bearings
I noticed that the sizes were close, so may be an option. Still open to offers . . .

As for the design, reasonably traditional layout so good start. But the gantry sides look too thin. Consider welding angle iron onto the 5mm plate, or some other upgrade. Same goes for the flat plates holding part of the Z axis rails on (if I understand the dwg).

Otherwise, for balsa and liteply it should get you going . . .

Barry