Thank you Rob for the detailed answer.

Got it. Metal box at least for the vfd, ideally for everything else.
By shielded box, do you mean just an earthed metal enclosure, or aluminium foil :P or like a faraday cage with chicken wire?

Out of curiosity, Clive, about the fire hazard, how hot do this components get?
I did it from particle board cause it.s easy and fast, and I put all components on a metal plate, actually on the side panels of the pc enclosure, as I dismanteled it. All panels beeing raised half an inch from the wood.s surface. I could not wait to have the cnc running, and was planning to upgrade after a few months of use, and yes, I.m aware it.s a crap and unprofessional design, but it seemed to me a resonable prop at the time.

And should I add an enclosure fan to the drivers as well, as I already have 2 for the vfd enclosure.