[TR] rust removers recommendations

[Randall]

> that doesn't mean I want
> laboratory grade acid splashing on my skin or eyes.

Actually, pure phosphoric acid isn't even a liquid.  But we weren't talking
about "laboratory grade acid" (whatever that means, most labs use mostly
dilute acids anyway).  The solutions commonly sold to remove rust, are
already pretty dilute.  I generally don't even bother with rubber gloves
when working with DX579 (although I do dilute it about 1:4 before using it).
Not saying it isn't dangerous, just that it's no worse than, say, chlorine
bleach or gasoline or a hundred other common household chemicals. 

> The question is how do you avoid using more than you need?

Easy, just take a look at what the stuff costs!

> What happens to the excess?

As you say, dilution.  Flush it down the drain.

-- Randall