Andy Dingley wrote:
On 22 Jan, 12:15, The Natural Philosopher wrote:

I exclude hydrochloric acid and ammonia, both of which blow your head
off with the fumes before you've actually used them for anything,
Rubbish.

Nothing beats ammonia for wood bending either..

You can't bend wood with ammonia in any concentration that's vaguely
safe to handle. You're not going to achieve much with .880, you would
(commercially) be looking at anhydrous and that's hard to work with.

I'd agree with your general point though - I use 26% ammonia for
fuming oak to darken it (another reason why it's not a good idea for
much bending) and even though ammonia is one of the few common
chemicals I'm at all sensitive to, a full-face mask (Avon S10) is all
I ever need to work with it.

Brick acid is simply a cheap way to get a pretty strong acid.

Define "strong" though, as that's a little more subtle for acids than
mere concentration. I use at least five workshop acids commonly
(sulphuric, hydrochloric, sulphamic, phosphoric, acetic) and two
rarely (nitric, chromic) and you have to choose according to task, not
just pick the most concentrated.

all of those work on limescale..you pick the one that attacks everything
attached to it the least ;-)