[TheForge] Re: acid

[Mike Spencer]

> ... use for the the others or different uses than the ones I already
> mentioned?

> 1 liter of Nitric acid

I've used it to etch my signature on art pieces where it seemed the
best way.  Paint-on resist and  a wax dam around the polished
signature surface.

I've never done it but reputedly you can remove a broken tap or drill
from mild steel by repeatedly dribbling concentrated HNO3 into the
hole where the acid will attack the hard tool steel faster than the
m/s and loosen the broken piece.  

I've also used it to etch the brass ball bearing cages from British
Leyland vehicles down to feathery thinness to make ear rings for a
woman who raced a Mini.

> 1 gallon of crystaline NaOH  (lye)

Excellent for degreasing/dewaxing a polished steel piece before
attempting a heat or chemical patina.  Boil the piece in an NaOH
solution.  Rinse thoroughly with water, possibly including
neutralizing with dilute acetic acid and further rinsing.  When I was
making a series of brass-inlaid belt buckles with heat patina as the
final step, traces of wax & oil I had used as a lubricant for the
chisels boiled out from under the inlay and spoiled the patina.
Boiling the buckles in NaOH between the chiseling and inlaying steps
fixed that.

> I know about safe handling of these chemicals thanks to OHSA
> training.

Oh, good!  So I can skip the horror stories. :-)

- Mike

-- 
Michael Spencer                  Nova Scotia, Canada       .~. 
                                                           /V\ 
mspencer at tallships.ca                                     /( )\
http://home.tallships.ca/mspencer/                        ^^-^^