CFM and RQ Gaps

["Ted Rosenberg" <Ted.Rosenberg-at-radioshack-dot-com> (by way of Terry Fritz <twftesla-at-uswest-dot-net>)]

Hello all: 

I do not believe the subject of Cubic Feet per Minute figures for those who
build coils using a static gap has been mentioned.

My coil, well into construction, will use a 15KV/60 NST. 
My gap, just finished yesterday, uses 9, 1-3/4 copper sweat couplers in a "Scot
D-Jochin" zig-zag arrangement. BTW, once this works, I have some neat shortcuts
for building such a gap.

But, I obviously need to blow some air on this zig-zag and the question is how
much air? 
Many discuss the electronics of the coil in detailed numbers. But I cannot
recall anyone throwing a CFM figure around. 

I can install anything from a vac motor to a couple of small 12VDC or 110VAC
fans. 
But the CFM ratings available are all over the place. You can buy 20CFM to
almost 200CFM. 
Where do you start? 
Unlike some who might have some fans in an old junk box, I plan to buy them. 

And while on this subject, is it absolutely required that the airflow NOT just
go down the length of the tubes but rather across and out slots cut in the
support slabs?

Comments are very welcomed. 
With thanks to all to let me get this far! 

Ted R