So the resume button has tentatively been pressed for this project, as I'm getting fed up hand machining bits of wood.

Some initial sketches have been done, so I can get an idea of component layout.
My current plans are wide enough to machine 4ft with the gantry on the long axis for better access.
I'm still undecided about length. 2ft would be enough, but having measured it's potential location, I think I could go to 4ft without any issue, which would increase versatility.

Gantry will be based around Jazz's tried and tested double profile L shape. I'm thinking 80x160 profile for this.
Where are people buying aluminium profile?
I'm aware of KJN, but my googling isn't turning up many other UK sources.

Main frame will be steel, and I'm thinking of using an epoxy poor to create the level surface for mounting rails.
I was going to go for either 50x50 or 60x60 5mm wall box for the bed frame, with probably something a bit bigger for sides where the linear rails will mount, but I'm currently wondering if stacking two of those would work. I think I need to work out how much bed clearance I'd like, before deciding on this bit.