[TheForge] Speaking of scrap...

[Saint Phlip]

On 5/28/06, Mike Porter <michael.a.porter at comcast.net> wrote:
>
> Phlip,
> I agree that cadmium presents a great danger when heated past its boiling
> point, which is 1409° F.


Mikey- water boils at 212 degrees. Does this mean it's totally inert at room
temperatures? Of course not.

> When cadmium containing filler alloys are employed
> in brazing, they should only be used with proper powered ventilation
> and an approved respirator.

Approved specifically for cadmium.

> The operator must also take the precaution of using heat monitoring
> devices (usually Tempilstiks(r)), and be careful to avoid overheating
> the part surface with a torch by using soft brush flames and constant >
torch movement.(Taking supplemental zinc daily is also recommended
> when a worker is exposed to any cadmium fumes or dust).

If they live that long. It'll help, with a sub-critical dose, but not only
does it have a very low critical dose, but even the zinc will do very little
but let you die more slowly.

It's rather similar to the iodine kept on hand for large doses of radiation
exposure. Ain't nothing gonna cure it, just slow the process down.

>You are correct that general hot work on cad-plated materials could be >
considered as a sign of insanity, and will generally result in the
> immediate collection of a Darwin award.

As part of his training, Rob not only saw the movies of the divers dying as
the rescuers tried to save them, but the autopsy pictures of their lung and
liver tissues.

And, the cadmium screw heads (3 10s, approximately) were at a temp of
roughly 65 degrees. The O2 was up at about 35%, from normal atmospheric
percentages of 21%, at a pressure of several (it varied) atmospheres. That's
well below the boiling point of cadmium, but the high oxygen content and
pressure increased the sublimation effect considerably.

> However, the only form of cadmium with which I'm familiar is hot-dip
> surface plating, which is similar to zinc in color when new, but which >
quickly oxidizes to a gray leaden appearance. Could you persuade
> your roommate to go into this "brass and bronze" appearing variety a >
little further?

> Mikey

Read Ries' commentary- he explains it well. And, btw, the note just previous
to this one was written by Rob. He just didn't think to sign it.

I've run into the cadmium plated fasteners- just didn't know what I had,
until Rob and I had this discussion. As you can imagine, I'll be checking
over my various bits of scrap.

Saint Phlip

Don't like getting old? Beats the Hel out of the alternative.

The purpose of life is not to arrive at the grave, a beautiful corpse,
pretty and well-preserved, but to slide in sideways, thoroughly used up,
totally worn out, proclaiming, "Wow! What a ride!"