On Sun, 10 Dec 2006 11:11:00 -0500, (Arch) wrote:

Sorry about your accidental injury, Jesse.

You, Robert and Andy raise a knotty question re the limits of paying
attention to the risks of injury in a woodturning shop. I may raise that
issue in a separate thread, but in this thread I hoped someone would
address the special problem if it exists at all, re inhaling the dust of
a dense inert metal alloy (dima). Dime Bombs in the Middle East will
almost certainly be news in the days to come.

As a woodturner I ask: what dima are in powdered metal turning tools?
Do they pose any special significant risks? If so are special
protective precautions necessary, feasible or worth the trouble and
expense? I think we have the experts to lay these questions to rest for
us here & now. If not, someone will know how to look the info up (or
down 'G') for all of us to share, since "The half of knowledge is to
know where to find knowledge".

Well, I am absolutely not an expert on the subject, but I have spent a
lot of time grinding metal in a professional capacity. It could be
dependant on your personal body chemistry, but the only metal dust
that ever made me so much as cough was when using a diamond wheel to
sharpen carbide. At a glance, that would be a mixture of diamond
dust, binder, carbide, cobalt, and/or tungsten. That was extremely
fine dust, and at least one of those did seem to build up in the body-
my guess is the cobalt, but all of it was pretty subjective based on
how I was feeling. That could have been affected by any number of
things.

If it is a concern, you might want to consider getting a grinder with
a coolant pump and drip tray- not only will it keep the dust down, but
it might make for a better sharpening experience as well.