View Full Version : Ross77's Z Axis Design

20-05-2013, 03:04 AM
Evening all. Heres my take on an easy to build and strong Z axis/carriage design when using supported rail. This is only a Concept design for bearing and rail orientation - final dims and size to suit cutting application.

Design Link: Concept supported rail Z axis design (http://www.mycncuk.com/forums/axis-design-construction/6134-concept-supported-rail-z-axis-design.html)

I think the difficulty with your idea lies with achieving sufficient accuracy on both axes, but particularly Z, to be able to mount the linear bearings. Normally people orientate the joints on Y such that at least one pair of bearings can be adjusted relative to the other, so assuming the rails are parallel that means the bearings will run smoothly. With your proposal, this could be done on Y or Z, but probably not both, which leaves the problem of machining the parts sufficiently accurately so that adjustment is not required. It's manageable if you have a suitable size milling machine, but probably impractical otherwise?

20-05-2013, 06:09 PM
I see your point but I don,t think its a deal breaker, shims in the mounting pockets or grub screws pressing on a metal plate between the bearing (like a jib in a dovetail) would easily give the required adjustment.