I like the idea of the trap for coolant- I wouldn't have thought of that! There's a guy in another thread saying he's getting problems with liquid freezing in his vacuum pipes. That trap would probably solve his problems- apparently his pipes freeze up with liquid and the vacuum fails to hold the part when machining which could be well dodgy!
Nice one Geof.
I'll point him to this thread.
[Edit]Here's his original thread
http://www.cnczone.com/forums/showthread.php?t=53871
[/Edit]