I'm starting a meetup in London for people interested in the future of
manufacturing : basically for people doing 3d printing, laser-cutting,
cnc-ing etc. to meet designers, CAD programmers and even people
working in "real" engineering.
Check it out at http://www.meetup.com/Future-Manufacturing/ if interested.
I'll try to keep hackspace members posted.
But just to point out, meetup.com is actually a pretty good tool for
organising this kind of thing (it exports event calendar data, sends
out automatic notifications and reminders, allows people to submit
suggestions etc.) Unless you have very strong ideological reasons
against, I'd suggest also joining the meetup on the meetup.com site.
It makes it easier for me to co-ordinate plus its useful for other
people who are joining to see who else is in the community. I'm sure
there will be a lot of overlap with the hackspace but the meetup will
be pulling in people from outside it too.