Thanks for the tip 3dTI.
Where is the clearance issue? Between Z axis pipes and X/Y bearings?
Think I’ll push ahead for now and see if I can bias clearances to suit.
Intent of the machine is to be extremely inexpensive and adaptable so I’d rather tweak the 3d printed parts (if possible) than chase more exotic or expensive pipe options.
If all else fails, I do happen to live close to an Ulrich Aluminium warehouse.