Date: Sun, 16 Sep 2007 18:49:46 -0500> To: cctech
at classiccmp.org> From: trag at io.com>
---snip---> Now carefully touch
the tips of the two clothes pin carbon rods > together and then slowly draw them apart.
TADA! Carbon arc.> > Vary the salt content in the jar to adjust the power.> >
I don't recall the instructions saying anything about not looking > directly at the
arc. Perhaps this method doesn't generate enough > UV to be useful/harmful? I spent
a fair bit of time staring at the > thing. Thirty-five years later I haven't
noticed any vision > impairment, but maybe I was young enough for my retina to
recover.> > It was quite the attention getter at the ES science fair. I suspect >
books in grade schools don't contain cool/dangerous projects like > this any more.
I only electrocuted myself once or twice by > touching the live bits of the
contraption...> > Jeff Walther
The light from these arcs would have a lot of UV. The UV just
depends on the temperature of the arc. The mercury vapor
lamp has peeks in its spectrum in the UV. I is different than an
arc. Arcs are just real hot.
I suspect that for any of there projects, they recommend
adult supervision. The only problem with that is that
more adults don't have a clue.
You can get a sun burn from arc welding as well. I was
about 5 feet away and watching a friend do some welding
for me. All I had was goggles and not a full face shield.
I looked funny for about 2 weeks.
Dwight
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