SD3 with "Z" Axis Ball Screw. (Page 2 of 2)

I can now answer this question.  Check out my other post on the print bed bed upgrade. 

http://www.soliforum.com/topic/4650/upg … print-bed/

While I was doing a heaterpad replacement I upgraded to the aluminum platform as well, and moved the ball screw to that platform.

The problem I encountered was the same as before, the ball nut is very tall and large in diameter.  When you bring the platform up to the top, the back edge of the nut hits the horizontal rod ("Y" motion transfer rod).  Not by much, only about 1mm.  So I offset the centerline of the ballscrew forward by about 2mm. This means that the screw and the vertical rods are no longer aligned, rather the screw sits 2mm forward.

To accommodate this, I also had to move the "Z" motor forward 2mm, so I elongated the 4 holes at the bottom of the case.  So now everything works OK, and the platform can move all they way up, with the nut clearing the horizontal rod by 1mm.

Let me know if you need any additional information.  It's not a very tough mod.  Actually this is a lot easier than the mods I had to do for the original wood platform.

You mean install it upside down at the bottom of the plate?  It wouldn't fit, the flange is too wide  The flange is 30mm (front to back), the inside width of the plate is 26mm. 

Then there are a couple of other problems:

Mounting it upside down would have cut the vertical travel by quite a bit, because I'm using a coupling flex nut at the motor side which already reduced the travel down by about 30mm, this would have reduced it another 30mm.

The there's the issue of actually removing the ball screw nut from the screw itself.  They already warn against doing it, because you can never get it back on correctly (all the recirculating balls are preloaded, so they'd fall out.

So it works great the way it is, and the solution to move the axis forward a couple of mm was more than adequate.

Edit:  I had the wrong dimensions in there, because my calipers were offset when I turned them on.  anyway, I fixed the flange and plate dimensions.

So we have to set z microstep to 800. Am i right? I have the simular 1204 ballscrew and i ll post the results