I got a bit done on the Z axis over the weekend. When I was laying everything out for the Z I decided that 4.5 inches between linear rails was not wide enough. So I welded on some 3/8inch plate in order to widen it to 8 inches center to center on the rails.

Starting the milled slot for the ballnut to travel
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Slot cut through and now cleaning up the edges
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Internal view showing 2 internal supports. I figured these were needed to help keep movement to a minimum when I cut the large slot in the tube. They had to be driven in with a sledge as they were a little tight but I got them in. They are welded in place by drilling 3/8inch holes in the box tubing and then spot welding through those holes.
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Begining the face milling process. I milled a linear reference for one of the rails. The curves are just the tool paths I had to take to make it all work as my mills travel isnt enough to do the whole thing in 1 pass.
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Here you can see the milled linear reference for the rail
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And a blurry picture of one of the rails test fitted
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