Right I have had an hour to play in solidworks so this is not very detailed its just an outline of the idea I am thinking of once I have ironed out any potential problems I will go in a bit more detail.

So once again 1200mm x 800mm bed current z axis 200mm ? good bad ugly?

z axis is based on 4 blocks sitting on a 200mm square footprint eg one on each corner of a 200mm square.

Adjustable bed for altering depths of material / things to machine.

twin ballscrew on the x axis, single on the y and z

concrete/ sand etc in the box section taken on board I will give that a go.

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