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crawling

updated tue 27 oct 98

 

Emily Pearlman on fri 15 nov 96

Hi All:

Over the years I've had my share of crawling and solved much f it through
the usual ways, but always had some (most annoying). Lately I realized
I've eliminated about 99% of it by wiping my greenware down with a damp
sponge before putting it into the kiln to be bisqued. I used to wash all
my bisque and still had crawling and now I think I dont need to even wash
it. Amazing! The big question is, why did it take me so long to discover
this?

Emily

Emily Pearlman-Pottery (clayfeat@echonyc.com)
http://humanarts.com/emilypearlman
http://www.craftweb.com/org/pearlman/pearlman.htm
(in NYC)

Maggie Woodhead on mon 26 oct 98

Hi Clayarters! Kia Ora!

I've been reading the posts on pinholing with interest as we
often have this problem or similar, I found changing the clay was very
successful and a lot of problems cleared up when I did that.
However there was one glaze which was giving me trouble over a
period of time It started to crawl quite badly after a spell of not
using it and nothing I did seemed to help, I even took off all the water
and replaced it with distilled water. Eventually MIchael Banks ( newly
joined Clayart - nice one Michael -) suggested I try adding vinegar to
counteract the effects of the borates dissolving and making the glaze
very alkaline. It worked! As far as the test was concerned! As soon
as I can get it onto a proper pot will see the results. Thankyou Michael
and perhaps you can give a more scientific explanation of this than
mine. Gherstley Borate is used more extensively by many Clayarters
than it is by potters here so this may be a problem that is solved by
using the old vinegar trick!

Good luck and
----Best Wishes Maggie----
maggie@clear.net.nz