Re: Chemistry and risk

On Thu, 16 Feb 2006, Kate M wrote:

> But that does bring me back to the method of measuring out dry dichromate
> and adding it to the gum/pigment....this is the riskiest method of working
> with the dichromates and so I strongly advise anyone doing it to do it ONLY
> under controlled conditions (in a fume cabinet and with a filtered mask,
> gloves etc.)

Kate, with all due respect to Sam Wang's genius as gum printer, that
method is... let's call it a personal quirk, not only not necessary, but
heinous. Also a LOT more trouble. Keep a saturated solution of am di in
a large (8 oz, for example) dropper bottle... that makes a lot of prints &
doesn't go bad. When you want dichromate, you measure out drops or
droppersful -- in 2 seconds, and no breathing or spilling dust. The
solution is mixed wearing a mask, spooning out the dry am di (NOT shaking
it out of the bottle) with the scale on newspaper. That way, as soon as
the measuring is done, you fold up the newspaper & dispose in sealed trash
-- so any stray grains that have floated out are removed.

Then, any time you open the bottle & remove some, you wipe the neck so a
single drop or two that lingers doesn't dry up & shed powder into the room
or on your hands.

And, needless to say, you don't touch the chemical, the emulsion, or even
the wash water with bare hands.

I myself am extremely reactive to chemicals on my skin, but have used
dichromates with these precautions for 25 years (so far) without trouble.
Your department claiming hazard may not be fightable, but that's like
saying drain cleaner is hazard... As mentioned on this list years ago (by
Bob Schramm ??), the only way to get it to actually explode or catch fire,
is either bang it in a metal pan with a hammer or light it with a match.
(But of course there's no use bothering factotums with facts... good
luck.)

P: If you want to get some without all the falderal, try a wood finishing
shop (eg Garrett Wade) -- am or k di are traditional wood stains, tho of
course as "vintage" are 5 times usual price.

Judy
Received on Fri Feb 17 17:01:25 2006