"Gordon" wrote:

Printed circuit card assembly involves heating a large amount of solder
(60/40) in a large pot with heaters and a pump in the bottom. This solder
melts just under 500F. It is held at 500 by the temperature controller via
the heaters. When the pump is turned on, the solder surges up thru some
screens, out the top of an opening making a solder wave. The printed circut
card is on a conveyer and passes over the wave thus soldering the leads to
the traces. And guess what. No lead fumes! As even Grandma has admitted.
Why? Because the heat is not high enuf!

I haven't actually sampled a wave solder operation for lead fumes, but
the ones I've seen seemed to be more or less totally enclosed and
ventilated so that people are not exposed. And other people's results
for similar operations seemed to bear this out. If people were not
exposed, I did not care whether there was lead fume or not.

However most "home" lead usages are not this closely controlled IME.

Now, I don't know the alloy, if any, used in wheel weights and I don't
know the actual melting temp. But I do know it is not high enuf to make lead
fumes.
Are there other dangers? You bet.
Spilling molten solder on yourself could really ruin your day!
Also wheel weights leave behind the little metal clips and lots of dross.
This all floats and needs to be fished out before pouring. Another good way
to get a nasty burn.
So, you do as you see fit and I'll do my thing and why don't we leave it
at that. ')

Gordon
"Rosalie B." wrote in message
.. .
Dave wrote:

On Wed, 05 Oct 2005 03:41:42 GMT, Rosalie B.
said:

So more heat
being applied WILL result in higher temperatures than less heat.

I'm afraid your physics is faulty.

I'm not surprised. I've never had any physics. Probably the terms
I'm using are wrong

I know that if I have a lot of something to melt or defrost, I have
to apply heat for a longer time, or apply higher heat than if I have
just a little bit or if the stuff is short and fat (like a turkey)
rather than long and skinny like a french fry (or a coil of solder).

And the part on the edges (like the skin of the turkey) will melt or
defrost first and get hotter than the stuff in the middle (like the
giblets) which are still cold and un melted or un defrosted..

If I heat something up in a pan, the stuff on the edges will get hot
and start to bubble first. It seems to me that the part of a liquid
or a solid that one is trying to liquefy that gets hot first would put
out moisture (in the case of water) or fume (in the case of metal)
while the part in the middle was still getting hot.



grandma Rosalie


grandma Rosalie

On 5 Oct 2005 14:33:03 -0500, Dave wrote:
///
I try to avoid getting dragged into the substance of playground arguments in
which I have no horse in the race.


Hmmm, by my count, Rosalie stacked up 11 contributions, and Dave was
close behind with 9 to this playg...er.. thread.

:-)

But let me throw a little factual stuff on the fi the vapor
pressure of melted lead is 1 mm Hg at 973 degC and and 10 mmHg at
1162 degC
(42nd Rubber Book) i.e 1316 parts per million (ppm) by pressure and
13 parts per thousand respectively for those two temperatures.

Brian W

On 6 Oct 2005 08:56:02 -0500, Dave wrote:

On Thu, 06 Oct 2005 00:23:11 GMT, Brian Whatcott
said:

I try to avoid getting dragged into the substance of playground arguments in
which I have no horse in the race.


Hmmm, by my count, Rosalie stacked up 11 contributions, and Dave was
close behind with 9 to this playg...er.. thread.

And how many of those 9 argued for or against the proposition that melting
lead to make a sounding lead would create lead dust, as opposed to the
validity of the argument being made for that proposition.

I used the phrase "the substance of" for good reason. The distinction is
apparently too subtle for your comprehension.



Hmmm....not only willing to conduct an extensive two-way ..er..
dialog, but able to make distinctions too subtle for my
comprehension.... That will show me - for importing
actual data of the numeric or scientific kind into this very special
dialog.

Brian Whatcott

On Mon, 03 Oct 2005 03:05:55 +0000, Courtney Thomas wrote:

Maybe a fisherman's outlet ?

Hopefully,
Courtney

Here's a thought. I haven't tried this but it seems like
it would work. How about a window sash counter weight.
They're the right weight and shape and they are designed
to be suspended on a line. If you go to a vendor that
installs windows they might have a pile of them that they
have collected when they replace old windows with new and
let you have one.

If not try:

http://www.kilianhardware.com/cwsascoun2.html

http://www.alchemycastings.com/lead-...%20Weights.htm

Bob

Adam...nice photos and a great set of project
photos on the main web site...good luck !!
she looks like quite a project !!....