Lolli Cook on mon 19 dec 05
Warm Solstice wishes
I have a Salt-water Jug I have been working on, The claybody does not seep
water, but after a few days of sitting out holding the salt dissolved in
water the salt appears in "crazing lines" on the exterior of the jug. These
are a project for a client which is slipcast in a ^5 casting slip, and
glaze fired at a ^6. I am sure that the interior glaze must be crazed
because it is allowing the salt to come through. as I have not done any
work prior to this in slipcasting maybe there is someone with suggestions
for me.
or just a glaze guru willing to help this young potter girl! I am hopefully
getting the MC6G for christmas,(crossed fingers) I am currently using a
Bailey's satin matt with titanium.
so suggestions, some routes to explore. . or is this common for salted water
and my journey is futile????
Much gratitude
Laura www.lollipots.ca
Laura Lea "Lollipots" Cook
604. 375.6509
www.lollipots.ca
Ron Roy on tue 20 dec 05
Hi Laura,
This can only mean the clay is still open enough to let some water through.
What clay is it - and are you firing it using cones?
Many clay are sold with an extended firing range and many clay companies do
not test their clays to make sure they do what they say they will do. In
fact there are some clay companies which do not assume you want to have a
vitrified body.
If you want to know how to test that clay to find out what the absorbebcy
is let me know and I will send instructions - it's not hard at all.
RR
>Warm Solstice wishes
>
>I have a Salt-water Jug I have been working on, The claybody does not seep
>water, but after a few days of sitting out holding the salt dissolved in
>water the salt appears in "crazing lines" on the exterior of the jug. These
>are a project for a client which is slipcast in a ^5 casting slip, and
>glaze fired at a ^6. I am sure that the interior glaze must be crazed
>because it is allowing the salt to come through. as I have not done any
>work prior to this in slipcasting maybe there is someone with suggestions
>for me.
>
>or just a glaze guru willing to help this young potter girl! I am hopefully
>getting the MC6G for christmas,(crossed fingers) I am currently using a
>Bailey's satin matt with titanium.
>
>so suggestions, some routes to explore. . or is this common for salted water
>and my journey is futile????
>
>Much gratitude
>
>Laura www.lollipots.ca
Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513
Ivor and Olive Lewis on thu 22 dec 05
Dear Lolli Cook,
It would be natural to assume that the body is not as mature as you =
might think it to be even if you clay is designated a maturing at Cone 5 =
and after being reheated to Cone 6 for your glaze firing.
But there may be an equally simple explanation.
If I accept you assumption that the interior glaze is crazed and also =
assume that the crazing spreads over the lip or rim of the object, then =
this phenomenon may be due to capillary activity which can take place =
even though the conduit for moisture is open to the atmosphere. The =
process will be slow and unseen unless you stain the water with a dye, =
but as the water reaches the outer wall it will evaporate and drop its =
load of Salt.
I suggest you test a sample by staining the salt solution with food =
coloring. You might also try to reveal crazing on the interior before =
filling with salt solution.
Best regards for the Festive Season,
Ivor Lewis.
Redhill,
South Australia.
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