Michell Follett on sat 18 jun 05
I'm told that using galvanized steel trash cans as a reduction chamber
during raku firing may be unsafe due to outgassing of the galvi when
heated. Does anyone know of a safer alternative? I've been searching
online for unplated steel cans, can't find anything. I've attended a
few workshops where galvanized garbage cans were used and they sure are
convenient, however, I'm trying to avoid toxic chemicals as much as
possible!
Thanks, Michell
Craig Clark on sun 19 jun 05
Michelle, there is indeed the possiblity of gases from the
galvanizing on the cans if you get them hot enough but that doesn't
usually happen with your normal post reduction activity. There is also
the immediate dispersal of smoke/fumes when the cans are used outdoors,
which is the safest way to go.This mitigates exposure. Be more
concerned with the fumes that come from inside the can when you pull the
lid than anything else. They can be quite caustic and will get you if
you don't take care not to inhale them.
Here are a few alternatives to the garbage cans: If you are well
enough above sea level you can always dig a hole into which you put your
pot and then cover the hole for the reduction. You can use whatever type
of untreated steel you want to do this and then seal the edges with sand
if your looking for deep coppers. This is low tech, easy to do, and has
worked well for me in the past (did it up in the mountains of
Bolivia.)......You can go to your favorite steel yard, get some steel
sheet (11 gauge is heavy enough) and have cylinders rolled at a good
fabrication shop. You could also have whatever type shape you want for
you reduction chambers fabricated as well. The down side of this is that
it is comparitevely expensive. The upside is that you can have various
size chambers made which will come in handy. You can either have them
made with lids that fit similar to the conventional garbage can lids or
you can just invert the chamber over you work for
reduction...........You can do like Robert Pipenburg does and just take
you pots from the kiln and quickly bury them in a mulch/ash type of
large flat "pit" by raking the reduction material up and over the pot.
You then slowly brush away the mulch and hose the piece as you go. The
down side of this is that copious amounts of smoke are produced. But
once again there is not can of any type......There is also a potter by
the name of Don Ellis who fires his copper matt pieces one at a time and
reduces them under pyrex bowls. You can look at his technique as well
as those of Randy Brodnax and James Watkins in a very good, technically
oriented book on alternative raku and firing techniques. It's called
"Alternative Kilns and Firing Techniques", by James Watkins and Paul
Wandless. I got mine online for about twenty bucks.
While it is always good to be concerned about possible noxious or
toxic by-products of any firing technique a little care will most likely
result in many years of safe, injury free firing. However, of the many
different firing techniques, raku is most probably the one that puts you
into the most direct contact with the fumes. So if you have a system
that is sensitive or you just want to limit your exposures then there
are a number of alternatives to raku to consider.
You could also consider wearing one of those really nifty scuba type
systems that are designed for some foundary uses. I had the opportunity
to wear one while pouring iron several years back and it was wonderful.
Nice cooling airflow and no fumes!! They were quite pricey even back
then though. If your interested just check out foundary safety supply
outfits.
Hope this helps
Craig Dunn Clark
619 East 11 1/2 st
Houston, Texas 77008
(713)861-2083
mudman@hal-pc.org
David Hendley on sun 19 jun 05
Mitchell, I'm no chemical expert, but I seriously doubt that a galvanized
trash can gets hot enough to emit toxic fumes when used as a raku
reduction chamber. The pottery is nowhere near the metal, and the
combustible material, due to lack of oxygen, cannot get that hot, as
it smolders rather than burns vigorously.
It is true that galvanized steel produces toxic smoke when heated
to a high temperature, such as when welding. When this happens
you can easily see the white smoke that is produced.
David Hendley
I don't know nothin' but the blues, cobalt that is.
david@farmpots.com
http://www.farmpots.com
----- Original Message -----
> I'm told that using galvanized steel trash cans as a reduction chamber
> during raku firing may be unsafe due to outgassing of the galvi when
> heated. Does anyone know of a safer alternative? I've been searching
> online for unplated steel cans, can't find anything. I've attended a
> few workshops where galvanized garbage cans were used and they sure are
> convenient, however, I'm trying to avoid toxic chemicals as much as
> possible!
>
Edouard Bastarache Inc. on sun 19 jun 05
Michell,
on a theoritical basis, if freshly made zinc oxide is
produced in your firing process, and you inhale some
of it, you may suffer from "metal fume fever", a flu-like
benign condition.
Later,
"Ils sont fous ces quebecois"
"They are insane these quebekers"
"Están locos estos quebequeses"
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
www.sorel-tracy.qc.ca/~edouardb/Welcome.html
http://perso.wanadoo.fr/smart2000/index.htm
http://www.digitalfire.com/education/toxicity/
pdp1@EARTHLINK.NET on sun 19 jun 05
Hi Michell,
Just cruise the Alleys of any City, or back streets of any Industrial or
older Commercial Area, and find a 30 or 55 Gal Steel drum...then make a good
refuse fire or Wood fire in it to burn off whatever outside paint or inside
residue of anything, and you are good-to-go.
They are free...
The kind where the whole top comes of and fits back on with a band clamp I
mean, not the solid-both-ends kind with the bungs, where you'd have to cut
one end out...
Phil
el ve
----- Original Message -----
From: "Michell Follett"
> I'm told that using galvanized steel trash cans as a reduction chamber
> during raku firing may be unsafe due to outgassing of the galvi when
> heated. Does anyone know of a safer alternative? I've been searching
> online for unplated steel cans, can't find anything. I've attended a
> few workshops where galvanized garbage cans were used and they sure are
> convenient, however, I'm trying to avoid toxic chemicals as much as
> possible!
>
> Thanks, Michell
Hank Murrow on sun 19 jun 05
On Jun 18, 2005, at 11:41 AM, Michell Follett wrote:
> I'm told that using galvanized steel trash cans as a reduction chamber
> during raku firing may be unsafe due to outgassing of the galvi when
> heated. Does anyone know of a safer alternative? I've been searching
> online for unplated steel cans, can't find anything. I've attended a
> few workshops where galvanized garbage cans were used and they sure are
> convenient, however, I'm trying to avoid toxic chemicals as much as
> possible!
Dear Michell;
I don't know about out-gassing from galvanized cans, but there is
another way to fabricate a can. At Anderson Ranch in the early '70s we
cut oil drums down to the height we wanted (being careful to wash all
combustibles out of them) and welded on 1/2" rod handles. They worked
fine and lasted forever.
Cheers, Hank
www.murrow.biz/hank
Steve Slatin on mon 20 jun 05
Liz -- Galvanization is zinc plating, either by
dipping in molten metal or by electrolysis.
Those of us firing to lower temps will use zinc in our
glazes because of its low melting point -- 419 Cent.,
but it boils at 907 Cent., which is about cone 010.
That's a temp that's reachable with some sawdust
setups, IIRC.
The fumes can cause a chemical pneumonia.
-- Steve Slatin
--- Liz Willoughby wrote:
> Just thought that I would chime in here. The
> galvanized trash can
> probably will not get hot enough when used for a
> raku reduction
> chamber, but it does get hot enough if you use one
> for sawdust
> firing. When I first started making sawdust fired
> pots many years
> ago, the fumes were terrible. Made you cough, eyes
> running, and
> standing anywhere near the can was almost impossible
> because of the
> fumes. This was before I found out what was going
> on....galvanized
> means treated with lead in some way, is that right?
Steve Slatin --
Frail my heart apart and play me little Shady Grove
Ring the bells of Rhymney till they ring inside my head forever
__________________________________________________
Do You Yahoo!?
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Snail Scott on mon 20 jun 05
At 11:01 AM 6/20/2005 -0400, you wrote:
>...galvanized
>means treated with lead in some way, is that right?
No, galvanizing is zinc plating. Still nasty
to inhale, but not lead.
-Snail
Ken Nowicki on mon 20 jun 05
In a message dated 6/20/2005, lizwill@PHC.IGS.NET writes:
This was before I found out what was going on....galvanized
means treated with lead in some way, is that right?
Hi Liz,
Not sure... but I think it means treated with zinc... not lead... but perhaps
someone with more knowledge can chime in here... anyone?
- Ken
Ken Nowicki
Port Washington, New York
RakuArtist@aol.com
- Charter Member Potter's Council -
Liz Willoughby on mon 20 jun 05
Just thought that I would chime in here. The galvanized trash can
probably will not get hot enough when used for a raku reduction
chamber, but it does get hot enough if you use one for sawdust
firing. When I first started making sawdust fired pots many years
ago, the fumes were terrible. Made you cough, eyes running, and
standing anywhere near the can was almost impossible because of the
fumes. This was before I found out what was going on....galvanized
means treated with lead in some way, is that right? Now, when I do
my occasional sawdust firing, I use a small brick kiln that I made,
and use an old kiln shelf for the lid. Mitchell, you can use any
kind of old bricks for this. It is also handy for burning leaves or
wood.
Meticky Liz from Grafton, Ontario, Canada
where the sun is shining, after a couple of days of good rain, and my
Japanese Tree Lilac is in bloom. (Kelly, I have many different kinds
of lilacs, that bloom from May to the end of June.)
>Mitchell, I'm no chemical expert, but I seriously doubt that a galvanized
>trash can gets hot enough to emit toxic fumes when used as a raku
>reduction chamber.
>It is true that galvanized steel produces toxic smoke when heated
>to a high temperature, such as when welding. When this happens
>you can easily see the white smoke that is produced.
>David Hendley
>
>----- Original Message -----
>>I'm told that using galvanized steel trash cans as a reduction chamber
>>during raku firing may be unsafe due to outgassing of the galvi when
>>heated. Does anyone know of a safer alternative?
pdp1@EARTHLINK.NET on tue 21 jun 05
Too...depending on the source or provenance of the 'Zink' used for the
'Hot-Dip', (see price-of-Zink, and price-of-Lead, as scrap for example, and
ask yourself if we do not discover people who think 'business is for making
money' and so on, ) when it is that method, and seeing how a lot of these
kinds of things now are blessed by 'nafta' to come here from other Sunny
shores...
There might just be pah-lenteeeeee of 'Lead' in it too...
Yup...
Lub,
Phil
el ve
Vince Pitelka on tue 21 jun 05
> Liz -- Galvanization is zinc plating, either by
> dipping in molten metal or by electrolysis.
> Those of us firing to lower temps will use zinc in our
> glazes because of its low melting point -- 419 Cent.,
> but it boils at 907 Cent., which is about cone 010.
> That's a temp that's reachable with some sawdust
> setups, IIRC.
> The fumes can cause a chemical pneumonia.
Steve -
I experienced "metal fume fever" several times back in the 70s when working
as a welder and mechanic. I was welding hot-dipped galvanized steel, and
just didn't know better a the time. In that case there was a high
concentration of zinc fumes rising from the weld, entering my welding
helmet.
Galvanized trash cans are usually electro-plated, and in that case the
galvanizing is a very thin coating. In an outdoor setting, the outgassing
of zinc fumes from electroplated galvanized trash cans used for post-firing
reduction or sawdust smoking would be so minimal and diffused as to be of no
concern. It is important to view these things sensibly in context, and the
reality is that galvanized trash cans and washtubs are very practical
containers for these purposes. Raku firing and sawdust smoking are always
done outdoors where there is good air circulation.
That said, we should always avoid breathing the smoke and fumes produced
during raku firing or sawdust smoking. Any of us who have been around raku
firing know that the smoke produced inside the post-firing cans is highly
flammable and an extreme irritant to the eyes and throat. That's a far
greater concern than minute amounts of zinc outgassing from the cans.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/
Edouard Bastarache Inc. on tue 21 jun 05
Steve,
not chemical pneumonia from inhaling freshly made Zinc Oxide,
but a benign flu-like syndrome lasting 24-48 hours treated by
Tylenol or Aspirin.
Later,
----- Original Message -----
From: "Steve Slatin"
To:
Sent: Monday, June 20, 2005 3:49 PM
Subject: Re: Galvanized steel cans - outgassing
> Liz -- Galvanization is zinc plating, either by
> dipping in molten metal or by electrolysis.
>
> Those of us firing to lower temps will use zinc in our
> glazes because of its low melting point -- 419 Cent.,
> but it boils at 907 Cent., which is about cone 010.
> That's a temp that's reachable with some sawdust
> setups, IIRC.
>
> The fumes can cause a chemical pneumonia.
>
> -- Steve Slatin
>
> --- Liz Willoughby wrote:
>
>> Just thought that I would chime in here. The
>> galvanized trash can
>> probably will not get hot enough when used for a
>> raku reduction
>> chamber, but it does get hot enough if you use one
>> for sawdust
>> firing. When I first started making sawdust fired
>> pots many years
>> ago, the fumes were terrible. Made you cough, eyes
>> running, and
>> standing anywhere near the can was almost impossible
>> because of the
>> fumes. This was before I found out what was going
>> on....galvanized
>> means treated with lead in some way, is that right?
>
>
> Steve Slatin --
>
> Frail my heart apart and play me little Shady Grove
> Ring the bells of Rhymney till they ring inside my head forever
>
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