Re: Darkroom Sinks for platinum work

erobkin@uwcmail.uwc.edu
Fri Feb 9 14:50:40 CST 1996

Awhile back I told the list that I had a program I could send that would allow
transfer of binary, and non-ascii data via email. I think that the recent
troubles with sending the density information could be avoided with its use.

However, the sender must have a program to prepare the data for sending.
There are many versions of this available from lots of different sources.
If needed I can send a copy.

The process is called Unix to Unix copy and there are two programs uuencode
and uudecode needed. I have a uudecode program, no I did not write it, that
is in itself a text file. All you need to do is access the email message
that contains it with any word processor, strip away all the extra stuff, and
save the result as a plain text file under an appropriate name. The
instructions are included in the file. The resulting text file is a uudecode
executable file under DOS. If you have the uudecode file I can uuencode a
uuencode file and send it via email so you can then uudecode it. You
will then be able to uuencode files to send via email for uudecoding. Sounds
like a Peter Piper picked a peck of pickled peppers game but it works well.

I can post this to the list if there is any interest.

Second, I have a comment with respect to Dick Sullivan's message about
fiberglass sinks and his comment about "head trips for months." The resin
system involved is most probably polyester. The fumes from that are very
penetrating, not all that unpleasant, and can cause permanent severe central
nervous system damage. Every exposure causes some damage which may or may not
be reversible. I stopped working with the stuff several years ago after a
three day headache from it. Your tolerance for pain may be greater than mine.

If the system involves large volumes of thick resin and small volumes of
watery hardener you are likely dealing with this. All the hardeners I've run
accross use methyl ethyl ketone peroxide which will be mentioned on the label
somewhere. Typical use involves several ounces, a few hundred cc's, of resin
to a few drops of hardener. The volume ratios are very big. Most autobody
fillers use this system although for these the hardener is often thickened
and dispensed from what looks like a small toothpaste tube. Work outdoors or
with huge ventilation. Darkrooms are inherently a bad place for this
system. As far as I am concerned there is no way to use this stuff safely
indoors without industrial stregth ventilation and masks rated for toxic
organic vapors.

Epoxy systems are more expensive but the hazards are easier to deal with. You
likey have an epoxy system if the resin and the hardner are both thick and
used in similar volumes. The resin may be honey colored. Anything from equal
volumes down to say 5 to 1. A better clue is the thickness. The main hazard
with epoxies is contact dermatitis from the hardener. Wear gloves. After
mixing the hazard is quite low unless you have been previously sensitized. In
that case you probably won't be able to go near this stuff. Dermatitis is
rare for casual users and you will most likely recover from it.

None of the above is absolute. People work with polyester for years without
apparent trouble and others can't go near epoxy hardeners from their very
first exposure. There are many other resin systems out there which mimic
the above descriptions and have entirely different characteristics. Read
the labels and in the U.S. at least you can get the safety sheets that go
with the products.

Take care, and stay away from polyester resin.

E. Robkin
erobkin@uwcmail.uwc.edu