Cate Loveland on tue 1 oct 02
My DH, who built my raku kiln and major domos the firing, has a jar of brass
millings left over after milling gauges. He wants to try to put the dust on
a tile raku fired with clear glaze to see what happens. I'm uneasy...we fire
outside, but when I asked someone at a foundry whether we could use the
millings for casting, they said no because of possibly poisonous fumes.
Has anyone tried this? I really haven't a clue what would happen...whether
the stuff would even melt, or whether if it did, it would crack the tile when
it cooled, or if it would really give off poisonous fumes. His last
experiment was trying to see if some industrial glass could be used for a
peephole for the kiln...we fired that, and had a puddle of glass which
fortunately didn't melt enough to drip off the shelf.
Any informed speculation would be appreciated.
Thanks!
Cate in AZ
Ababi on tue 1 oct 02
Hello Cate
Which fumes?
Copper you use anyway
Zinc might be the problem Through It sublimes at 1800C
Raku is a dangerous business!
Try it this way:
Take bowl. apply on a WHITE glaze with TIN! Around at the top, spread the brass like
it was salt. Imagine to yourself that YOU LOVE A LOT OF SALT! and glaze.
Teat two: To 04 majolica glaze add some, 1-3% of this powder mix well and fire. You
will get either white with green to gray speckles or turquoise with gray speckles.
Test three , mix a little with your claybody, her and there than raku or saggar or any
other firing. You should thank him for this pail of gold!
If you have patient, role around in my site, many ways of using brass chips
Ababi Sharon
http://members4.clubphoto.com/ababi306910/
---------- Original Message ----------
>My DH, who built my raku kiln and major domos the firing, has a jar of brass
>millings left over after milling gauges. He wants to try to put the dust on
>a tile raku fired with clear glaze to see what happens. I'm uneasy...we fire
>outside, but when I asked someone at a foundry whether we could use the
>millings for casting, they said no because of possibly poisonous fumes.
>Has anyone tried this? I really haven't a clue what would happen...whether
>the stuff would even melt, or whether if it did, it would crack the tile when
>it cooled, or if it would really give off poisonous fumes. His last
>experiment was trying to see if some industrial glass could be used for a
>peephole for the kiln...we fired that, and had a puddle of glass which
>fortunately didn't melt enough to drip off the shelf.
>Any informed speculation would be appreciated.
>Thanks!
>Cate in AZ
>______________________________________________________________________________
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Mike Gordon on tue 1 oct 02
Hi,
He's talking about "yellow brass" which contains zinc which smokes when
heated past the melting point, breathing the fumes will get you sick. I
can't remember the exact melting temp but can look it up if you want me
to. Mike Gordon, Walnut Creek, Ca.
Snail Scott on tue 1 oct 02
At 12:38 AM 10/1/02 EDT, you wrote:
>My DH...has a jar of brass
>millings...He wants to try to put the dust on
>a tile raku fired with clear glaze to see what happens...
>I really haven't a clue what would happen...whether
>the stuff would even melt, or whether if it did, it would crack the tile=
when
>it cooled, or if it would really give off poisonous fumes...
>
Most brass alloys will melt at around 1800=BAF, a bit=20
higher than most raku firing. It may turn black and=20
leave a greenish mark surrounding it, or the glaze=20
may cover it leaving a mark. Depends on the glaze=20
and the size of the millings. I doubt it would crack=20
the tile.=20
The 'poisonous fumes' you were warnes about are=20
probably from zinc, a major component of many brass=20
alloys. Zinc fumes are indeed nasty and not to be=20
sniffed. Brass also contains a lot of copper and some=20
have a little manganese, too, which is also not a good=20
fume at all. 'Metal Fume Fever' is the term generally=20
applied to the symptoms of exposure.=20
However...now that I've gone and freaked you out good:
The amount of fume that you will get from millings=20
scattered on a few pieces is small - less exposure=20
than a welder might get in a few minutes of work, I'd=20
guess, even if you were standing directly in the=20
vapors. (I wear a respirator to weld, though; I've=20
felt the effects of breathing metal fumes.) And many=20
glaze firings give off similar fumes anyway. You=20
weren't standing around breathing them either, were=20
you?
My synopsis? Go ahead - it won't be any worse than=20
a regular firing. But don't go sniffing fumes, even=20
if there aren't brass bits in your kiln!
-Snail
Reno, NV
Phil Smith on tue 1 oct 02
Brass is an alloy of consisting mostly of copper and zinc. with up to 6%
lead depending on the alloy. The melting point being between 1616 -1841
depending on the alloy.
Be careful.
Phil:
vince pitelka on tue 1 oct 02
> My DH, who built my raku kiln and major domos the firing, has a jar of
brass
> millings left over after milling gauges. He wants to try to put the dust
on
> a tile raku fired with clear glaze to see what happens.
Bad idea. Brass filings contain copper, which might do some nice things,
but they also contain zinc, which will produce poisonous fumes.
Best wishes -
- Vince
Vince Pitelka
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Home - vpitelka@dtccom.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
http://www.craftcenter.tntech.edu/
Tom Buck on tue 1 oct 02
Cate L:
The term "brass" is used for a broad range of copper-zinc metal
mixtures (alloys). and there are special Brass alloys that contain
lesser amounts of manganese, lead, and tin.
If the brass fines were used in a Raku firing, and you stayed
below Cone 06 (say Cone 08/07), the copper fumes would be quite low
(copper metal melts at 1083 oC (Cone 04+). But Zinc metal fumes would be
very dominant in the fumes from the kiln - zinc metal melts at 416 oC,
boils at 907 oC (Cone 011/010). and the lead and tin and manganese, if
present, would be in the fumes in a substantial amount as one approached
Cone 07. Hence, the fumes, if inhaled would damage the lungs.
so, you are taking a major risk to fire brass fines unless the
kiln is well ventilated and the fumes expelled well away from the kiln
itself (that is up a chimney into a prevailing wind).
we wrap some raku pots in fine copper wire and feel that this use
of metal is reasonably safe. but I'd be against using brass wire, etc.
til later, peace. Tom B.
Tom Buck ) -- primary address.
"alias" or secondary address.
tel: 905-389-2339 (westend Lake Ontario, province of Ontario, Canada).
mailing address: 373 East 43rd Street, Hamilton ON L8T 3E1 Canada
Edouard Bastarache on tue 1 oct 02
Indeed Vince,
"Bad idea. Brass filings contain copper, which might do some nice things,
but they also contain zinc, which will produce poisonous fumes.
Vince"
freshly made zinc oxide fumes may cause "metal fume fever".
Fumes of copper oxides (red and black) may do the same.
Later,
Edouard Bastarache
Irreductible Quebecois
Indomitable Quebeker
Sorel-Tracy
Quebec
edouardb@sorel-tracy.qc.ca
http://sorel-tracy.qc.ca/~edouardb/
http://perso.wanadoo.fr/smart2000/index.htm
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