Jean Lutz on tue 30 nov 99
I either have another mysterious problem or I've done something really stupid.
I thought that when you wanted to suspend something to fire it you put it
on nichrome(sp?) wire.
I have 6 small children's hand prints that I made out of a paper clay slab.
When I glazed them (low fire) I hung them on a piece of nichrome suspended
across 2 kiln shelf supports. The span was about 8 1/2 inches. The hands
are about 1/8 inch thick and the largest is maybe 4 inches long.
I fired to cone06 and the wire slumped - of course the hands moved and
stuck to each other as well as the "catch piece" I had under it.
If nichrome is not the right material to use - what is??
If nichrome IS the correct material - what went wrong???
Jean Lutz
jlutz@azlink.com
Scottsdale, AZ
chris@euclids.com on wed 1 dec 99
> I fired to cone06 and the wire slumped - of course the hands moved and
> stuck to each other as well as the "catch piece" I had under it.
> If nichrome is not the right material to use - what is??
> If nichrome IS the correct material - what went wrong???
> Jean Lutz
Hi Jean,
My guess would be that the wire was too thin. Do you know what gauge wire
you used ?
It is true that nichrome wire will not sag where chromium/iron/aluminium
wire will, as in a lid element for a glass kiln (most manufactures use
nichrome for this application to help prevent sagging) ... but when used to
support weight it does have the potential to sag. Try a heavier gauge wire
(overkill here is OK ... it would have saved your pieces).
chris
chris@euclids.com
www.euclids.com
800-296-5456
Shirley Samuelson on wed 1 dec 99
Jean,I don't know how high you were firing the nichrome, but an experience
I just had with raku firing suggests that the thickness of your wire - or
thinness-- could have contributed to the problem. Last week I strung up
some Christmas ornaments on nichrome for rakuing. I had to use a lighter
weight wire that would fit in the holes-to-hang-by on some smaller pieces.
The wire seemed very adequate for the small items, but for insurance I
secured each piece with a twist to the rack at each end and then supported
them crosswise underneath with heavier wire (on which ornaments were also
hung). It seemed like belt and suspenders with the wires stretched and
secured plus the double support. But, the thinner wire stretched into deep
loops nevertheless and, of course, the ornaments stuck together. The
heavier wire with heavier pieces hanging from it held up well. I imagine
your kiln is aa bit warmer than the raku temp, so you likely need some good
and heavy stuff.
Shirley Samuelson
Cindy Strnad on wed 1 dec 99
Jean,
Nichrome wire will bend if you string too many beads on it, which is
inconvenient as bead racks are made of nichrome wire. It can't take a lot of
weight, and would never manage the load and span you describe. Low fire
glazes can be stilted without a lot of rough edges to buff off later. Just
stilt the hand prints. If there are glaze sharpies when you remove the
stilts, you can get them off with either an aluminum oxide or silicon
carbide stone. Best if the stone is a Dremel bit, but a knife sharpening
stone will work, too.
Cindy Strnad
Earthen Vessels Pottery
Custer, SD
Paula Sibrack on wed 1 dec 99
Jean, Nichrome wire is the right stuff to use here, but it comes in various
gauges. The one you used wasn't heavy enough to span the 81/2 inches. Try
thicker nichrome wire, or more simply make the span shorter with more
supports between hanging objects. Paula Sibrack Marian, in the woods of
Sherman, CT
Vince Pitelka on thu 2 dec 99
> I fired to cone06 and the wire slumped - of course the hands moved and
> stuck to each other as well as the "catch piece" I had under it.
> If nichrome is not the right material to use - what is??
> If nichrome IS the correct material - what went wrong???
> Jean Lutz
Jean -
The solution is to anchor the ends of the wire. If the wire is simply lying
across the two supports, then very little weight will make it slump. Make a
pair of heavy, hollow Christmas-tree shaped pedestals, with a vertical hole
in the top of each one, and bisque-fire them. Bend about 1" of the wire in
a right-angle one end, string your objects to be fired onto the wire, and
bend another right angle (in the same direction) in the other end of the
wire. Insert these two right angles into the vertical holes in the top of
your pedestals. This will hold the wire very securely, as long as the
pedestals are heavy enough. Needless to say, the pedestals can be re-used
indefinitely. Also needless to say, after you fire you will probably have
to snip the right angle off one end of the wire to remove the objects being
fired (depending on the size of the holes in the objects). The wire will be
an inch shorter the next time you use it, but the cost of the wire is
minimal as compared to the advantages of this system.
Good luck -
- Vince
Vince Pitelka
Home - vpitelka@DeKalb.net
615/597-5376
Work - wpitelka@tntech.edu
615/597-6801 ext. 111, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166
Jean Lutz on fri 3 dec 99
Shirley,
I fired to cone 06. I didn't get the heaviest wire available but the next
one down. The only reason for that was that I was afraid that I wouldn't be
able to bend the heaviest one to fit into the holes of the supports. I'll
try the thicker guage one see if that makes a difference.
I'm not real sure I understand how you supported you pieces but I'll try to
rig up extra support the next time too. Thanks
Shirley Samuelson
Subject: Re: nichrome wire
----------------------------Original message----------------------------
Jean,I don't know how high you were firing the nichrome, but an experience
I just had with raku firing suggests that the thickness of your wire - or
thinness-- could have contributed to the problem. Last week I strung up
some Christmas ornaments on nichrome for rakuing. I had to use a lighter
weight wire that would fit in the holes-to-hang-by on some smaller pieces.
The wire seemed very adequate for the small items, but for insurance I
secured each piece with a twist to the rack at each end and then supported
them crosswise underneath with heavier wire (on which ornaments were also
hung). It seemed like belt and suspenders with the wires stretched and
secured plus the double support. But, the thinner wire stretched into deep
loops nevertheless and, of course, the ornaments stuck together. The
heavier wire with heavier pieces hanging from it held up well. I imagine
your kiln is aa bit warmer than the raku temp, so you likely need some good
and heavy stuff.
Shirley Samuelson
Jean Lutz
jlutz@azlink.com
Scottsdale, AZ
Jean Lutz on fri 3 dec 99
Cindy,
Thanks for the suggestion to stilt them. That just never occured to me as I
was so focused on hanging them from the holes in them. Duh! I also thought
that since they were from paper clay they would be lighter than usual and
be ok.
I wish someone would invent a brain drain/transplant so I don't have to
always learn the hard way.
From: Cindy Strnad
Subject: Re: nichrome wire
----------------------------Original message----------------------------
Jean,
Nichrome wire will bend if you string too many beads on it, which is
inconvenient as bead racks are made of nichrome wire. It can't take a lot of
weight, and would never manage the load and span you describe. Low fire
glazes can be stilted without a lot of rough edges to buff off later. Just
stilt the hand prints. If there are glaze sharpies when you remove the
stilts, you can get them off with either an aluminum oxide or silicon
carbide stone. Best if the stone is a Dremel bit, but a knife sharpening
stone will work, too.
Cindy Strnad
Earthen Vessels Pottery
Custer, SD
Jean Lutz
jlutz@azlink.com
Scottsdale, AZ
Ray Aldridge on fri 3 dec 99
At 08:55 AM 12/3/99 EST, you wrote:
>----------------------------Original message----------------------------
>Shirley,
>I fired to cone 06. I didn't get the heaviest wire available but the next
>one down. The only reason for that was that I was afraid that I wouldn't be
>able to bend the heaviest one to fit into the holes of the supports. I'll
>try the thicker guage one see if that makes a difference.
>I'm not real sure I understand how you supported you pieces but I'll try to
>rig up extra support the next time too. Thanks
>
Jean, another approach, which is a little more trouble but may be more
reliable, is to suspend each ornament from its own hook. Make an S-hook
for each ornament and hang the hook over a kiln post which is supported
horizontally by two other kiln posts. You can hang a number of ornaments
from each crossbar you set up. This takes a bit more wire, but wire is
cheap. That way you don't have to worry about the wire bending.
Ray
Aldridge Porcelain and Stoneware
http://www.goodpots.com
Jean Lutz on sat 4 dec 99
Vince,
Thanks for your reply. Unfortunately I did pretty much exactly what you
suggest. I bent more than and inch of each end of the wire and put them
into the holes of shelf supports.
Jean
The solution is to anchor the ends of the wire. If the wire is simply lying
across the two supports, then very little weight will make it slump. Make a
pair of heavy, hollow Christmas-tree shaped pedestals, with a vertical hole
in the top of each one, and bisque-fire them. Bend about 1" of the wire in
a right-angle one end, string your objects to be fired onto the wire, and
bend another right angle (in the same direction) in the other end of the
wire. Insert these two right angles into the vertical holes in the top of
your pedestals. This will hold the wire very securely, as long as the
pedestals are heavy enough. Needless to say, the pedestals can be re-used
indefinitely. Also needless to say, after you fire you will probably have
to snip the right angle off one end of the wire to remove the objects being
fired (depending on the size of the holes in the objects). The wire will be
an inch shorter the next time you use it, but the cost of the wire is
minimal as compared to the advantages of this system.
Good luck -
- Vince
Jean Lutz
jlutz@azlink.com
Scottsdale, AZ
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