Thanks Kered - sounds like a cost saving option, although I'm not sure I'd trust myself with self made high pressure tanks. Maybe one to add to the list to try:)
I've been spending most of my time on wood recently so not progressed the mist coolant plan at all as yet!
Top of my list for improvements/purchases now are

- handheld wireless controller for UCCNC (as sticking the laptop on the bandsaw table while I set part zero isn't ideal)
- Improve the table/spoilboard combination.

Currently I have a sheet of 12mm ply on top of the base's cross pieces which is drilled and inserted T nuts. Problem is sometimes they drop out the bottom as the bolt knocks them out when trying to fix something , which is a pain. Plus 12mm ply isn't the most stable material.

Current options - either some aluminum T-slot, steel t-slot , pre drilled and tapped steel grid plate or buy a sheet of aluminum then surface and use the machine to "drill" a grid of holes.
I don't have much Z height so needs to be <20mm maximum.

Anyone tried these or have any comments?

Thanks!