Good afternoon all, this is my first post, so please be gentle as I ask what must be obvious questions.

I am totally new to this world of CNC wood routing and am a bit confused by the use of a vacuum bed to hold material in place while cutting, the principle is obvious, but what are the minimum sizes of, for example, plywood, that can be held securely and safely with this system?

Also, if I cut through a piece of plywood, for a hole or an outline cut, how does the vacuum be maintained? what happens to any sawdust / cuttings which are produced? do they get sucked into the table?

The pictures appear to show a compressible junction to make the seal to the wood, how does the thickness of this be accounted for when milling totally through a pieces of plywood? surely it must be variable according to the air pressure? and therefore alter the height of the work piece? or have I just not got the idea correct at all??

As I will be mainly machining plywood and board hardwood into sizes ranging from 100mm square up to 300 x 900, is it a viable way for me to secure my work? is it worth the cost to buy one, I have been quoted £500 for a 600 x 900, or the time to make one?

Sorry for what must appear basic questions.