Can I pick your brains? How would you solve this puzzle....

[HankMcSpank]

Me again, had the chance to mull this a little.

Here's the immediate problem - just about every implementation of gun drilling has the drill static & the workpiece turing - that's fine when your workpiece is circular (gun barrel, kids musical recorder etc)...just lob the workpiece in a collet - it's perfect centred...job done.

But if the workpiece is a guitar neck (ie odd shaped!), then that's not gonna work very well (to much potential for it to be misaligned ...especially at the far end)

Therefore I reckon I need to have the gun drill bit turning & mount the guitar neck on a static table/bed - the problem here is, gun drills always have compressed air squirted down their centre (to expel the chips from the cutting end) ....so how do you supply/maintain compressed air down the centre of a drill bit that is turning? (ie what's the name of the part that allows a static pneumatic hose to connect to something that is spinning)