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breakage with horse hair raku and that orange color

updated sun 11 apr 04

 

Vicki Hardin on sat 10 apr 04


I had some breakage with the use of horse hair and find that it often =
happens when you take the work to too high a temperature. Of course =
this is all dependent on your clay. Really, you only have to get the =
work to a temperature high enough to ignite and carbonize the horse =
hair. It has been a while since I did this and this is off the top of my =
head but, in my experience at 1800 most of the horse hair burns out. I =
would suggest pulling at around 1400 because a pot will ignite paper at =
1100. What you want to do after pulling the pot is to test with your =
hair. If you find that the hair burns off, wait until the pot is to the =
temperature that it starts accepting the carbon. Also, I find that the =
real shock to a piece of clay is taking it out of a kiln and putting it =
on a cold surface. I found that I cut the loss entirely by heating a =
brick for the piece along with the firing. After reaching temperature, =
I would pull the brick and then the pot, which went on the brick causing =
it to cool more slowly with less initial shock.=20

That orange color can be achieved by the use of ferric chloride, which =
can be obtained at Radio Shack. Ask for echant. It is very nasty =
stuff, so, wear a respirator that has the filters designed for toxic =
fumes. Those white hospital masks will not do. I use a preval sprayer, =
seems to be the best way to get it on. I have seen people spray this on =
their work when it comes out of the kiln. Too many fumes for me. I do =
it before it goes into the kiln.

Best Wishes,
Vicki Hardin
http://ClayArtWebGuide.com

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