I'll send a PM with email address and we can arrange things that way.

For public consumption:

My welding is crap, people come to look and laugh. But the machine works and it hasn't fallen apart yet. No-one is going to mistake me for a certificated welder but it shows that it doesn't have to look perfect to work. Steel is very forgiving like this. BTW, my steel came from Austen Knapman who are even nearer you than me. Their online prices aren't too bad but call or visit them for better prices.

My machine runs off a single 13A socket, control box, VFD, PC and all. Hasn't blown a mains fuse or tripped a RCD yet.

I use 3Nm Nema 23, 2 on X and 1 on Y and Z. When I built it 4Nm weren't available although I might use them today. These motor sizing calculations are interesting but at the end of the day, it comes down to Nema 23 or 34 for typical "home" size machines, and given that Nema 34 will often reduce performance you don't use them unless you really need them. Big Nema 23 costs little more than small Nema 23, extra torque available more than makes up for extra inertia - no-brainer really. Just watch for low inductance and 8-wire so you can parallel-connect. 68V linear power supply, drivers to match - that bit of the design's done! Sometimes rule of thumb beats pages of sums....