Coolant on a little desktop mill (ie a Sherline)

Hello again my inexhaustable CNC army, :)

Since I got the 10,000RPM pulley set for my Sherline (I highly recommend
this to anyone doing CNC on a sherline, the performance of phenomenal!)
I have been able to cut a heck of a lot faster (good), but for the first
time I am running into problems with cooling (bad). The motor and
spindle/pulley part is all fine, but the workpiece I was working on
(aluminium) got pretty warm.. As the part is now pretty small it heats
up way too hot for me to touch with even a few minutes of machining, I
also have to continually spray WD40 on the cutting tool when making
plunge cuts to prevent it getting ali welded to it and resulting in a
lollipop of almiminum.

So here's my question.
Cooling Sherline/How?


Since a sherline was never designed for cooling in mind, I imagine the
leadscrews and other bits of ferrous metal are going to corrode
horribly! Also, while my mill is somewhat nicely shielded with clear
plastic panels, I am pretty worried about spraying coolant all over my
workroom (my TV room/loung too, incidentally).

What's a nice cheap solution for a machine of this size, or an elegant
one?
Will a windscreen wiper pump do?

Can I use WD40 as coolant instead of that nasty yellow stuff? That way I
get lubrication for free and my mill will never corrode (or does this
mean that fine dust will get into the ways and grind my machine
instead?)

Lots of questions, but I guess it's something which seems simple and may
not be... (like many CNC things, experience will show the best answer)

Thanks again,
Abby