Robin, your offer is very generous, thank you very much. Will send you a PM.

Did not realize how critical these ballscrews are to the build, and how much thinking has to go to them.

The X-axis, which I have so far thought as being "the piece of cake" in this project, and hence did not really think about it much.

Today thought better still check available space for X-axis ball screw.

- X -axis ball screw would have to go through this hole:

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- The hole height is equal to 28.66mm, which sounds great when you think it is only a 16mm ballscrew to put in there.
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- However it comes so close, because the ball nut height = 40mm, and the nut must clear the moving "top deck" (which slides over the ball-nut).
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Think there will be only 0.66mm of air underneath the screw, if one will go for 16mm screw. (and if the screw really is 16.00 mm). Challenge is, that one can not move the ballscrew higher, because then the ball nut would not clear the sliding "top deck".

A bit frustrating perhaps to just measure and measure, when one wants metal chips and sparks to fly. But guess you really don't want buy ballscrews that are only good to post to classifieds section... so slowly it goes. :)