CNC Flood Coolant?

This may get axed as off topic - and if so I apologize and would
welcome people to respond off list, its just that I know of no other
group that would have good ideas.

When I'm machining manually, I don't mind so much using the squirt
bottle for coolant supply. However, I'm not so sure that's going to
cut it when I get the CNC running so I wanted to setup an easily
controlled flood coolant system (but cheap - since I'm good like
that). I was going to try building one using a windshield washer
pump. You can basically get them next to free (if not free) at a
junkyard and they're easily controlled with a dc relay off the
parallel port. Has anybody tried this? Anybody know any good
reasons why this may not work? The only concern I have is duty
cycle, but if another pump is practically free, maybe its not an
issue. THoughts?