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help! bad crackle on my raku.

updated sat 4 jul 98


Daryl Baird on fri 3 jul 98

Greetings All,

I hope everyone's shows are going well and that the winds and rains are
cooperating. I'm heading out for a show myself but thought I'd ask for
some basic raku help before loading everything up.

We used to get good, reliable crackle in our raku with good strong black
lines but can't seem to do it anymore. I've read back through all my
raku books and I've tried a couple of raku glazes from Piepenburg's book
(Donna's White) and I've used Branfman's base white.

I mixed them thick and applied them thickly (four coats). I fired to
around 1900 degrees, according to my pyrometer. I saw a shiny melt but
I didn't see the preliminary bubbling and smoothing I used to see. I
pulled the pieces out pretty fast but held them out of the kiln hoping
to hear some pinging. I didn't hear anything and went ahead and put
each in the can. I burped the can after about a minute; adding more
newspaper. I burped it again a minute or so later then left it to
cool. NO SIGNIFICANT CRACKLE!! And some of the pieces are on the shard
pile because they cracked. Gad!

I'm suspicious of everything I'm doing now. My clay body is ^10 B-mix
I tried putting only one coat of glaze on but still no crazing. Should
I be using something touted as "raku clay"? Never have.

Advice, PLEASE! I'm going to invest in some of Laguna's raku clay but
tips on firing/reducing/burping/cooling are welcomed with open tongs.

Thanks in advance,

Daryl Baird
Loveland Artworks
Loveland, CO

P.S. Just a reminder, I'm still very much in the search of contributors
to my
book on extruders and extruding to be published next Spring by American
Ceramics Society. If you're interested, or if you know someone who
would be, please drop me a line. Thanks!