Hi Noel
I liked your etching instruction. Easy to understand and to follow.
There’s no magic nor danger as long as one knows what one is doing
and aware of the fact that there are chemicals involved.
This for Kerri: Always avoid breathing vapor although it is not
nitric acid coming out of the bath that needs to be filtered but
nitrous gases (and not healthy).
BTW. When I get nitric acid on my skin it turns to yellow spots
until it (the damaged skin) wears off.
I’ve done etching on and off for the past 30 years, commercially,
industrially, small scale and for home use (as a teenager). I have
always used acids, hydrochloric, sulphuric, phosphoric, acetic and
nitric, sometimes spiced with a little hydrogenperoxide, all
depending on the material. The only caveat is hydrofluoric acid to
etch glass, you’ll have to be careful and use some protection, I’ve
never done it though.
Imagetransfer can be done in many ways, you use the cheap and modern
way. It can also be done with silkscreen printing an acid resistant
ink or lightsensitive emulsions or laminates that are exposed with a
photographic film/pattern and processed prior to etching. The liquid
resists seem to be scarce nowdays. These give better (thicker)
protection to the acid meaning less repairwork. The way you cover
both sides with a resist pattern is THE way to success. My greatest
problem is to estimate the potential undercut, it can be a problem
in heavy gauge. People involved in model railways sometimes make
their own wagons, etched all through in thin brass plate after
detailed designs.
My experience with the transfer tecnique does make me ask one
question? When you say acetate I suppose you mean polyester based
overhead foil. Most laser printers have a very hot fuser unit and
acetate wouldn’t survive. Also that if you have any means to control
the print/copy I would imagine a heavier toner deposit would be
preferable.
michaela