@Doric
That comment about the leadscrew not being a type of thread narrows things down a bit, so in that case, it's definitely an ACME screw, cheers!

It's a desktop CNC machine for cutting wood and aluminium etc, basically a computer-controlled milling and cutting machine, it's often referred to as the '3020T'.  There's like a hundred variants of it though, all with the same name, which really helps.  I was just looking for some close-up photos I took of the thread to show to someone, was going to post it here but can't find the bloody thing, looks like I must have wiped it.

@RorrKonn
Well yeah, of course I know about the Cyber-crime that goes on, it's just one many of the reasons I don't feed tablets and smartphones with my data.
Sometimes I think there is no cure for certain breeds of muppet.

BTW, I have some good news and bad news for you, so which do you want first, the good or the bad?

@Shane
The system here is equally 'rigged'.