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kiln shelf won't retain kiln wash

updated thu 19 jun 08

 

Carole Fox on tue 17 jun 08


I have one kiln shelf that won't retain kiln wash. I coat it the same as
all my other shelves, which do not have this problem. The kiln wash dries
with a smooth surface and looks fine before firing. After one firing of
this shelf, all the kiln wash has crackled and flakes off easily (it
literally just falls off). This leaves the shelf surface looking perfectly
clean, as if it has never been fired before. I have to be careful removing
the shelf from the kiln, to avoid flakes of kiln wash getting all over. I
have never coated any of my shelves with anything other than the same kiln
wash, so I am curious to know why this one behaves differently. I tend to
avoid using the shelf because I have to recoat it before every firing, and
would like to know if there is anything I can do to prevent the flaking.
The only difference I can see between this shelf and the others is that it
is thinner than the others by 1/16 or 3/32". There are no manufacturer's
marks, and the supplier from which I bought it went out of business.

I suppose I can quit using kiln wash on it and just use it for bisque
firing, but if any of you can shed light on this mystery, I would like to be
enlightened.

Thanks,
Carole Fox
Dayton, OH

PS - the archives, after working well for several days, are so slow again as
to be unusable.

David Martin Hershey on tue 17 jun 08


Hi Patti and Carol,

I know this may sound kinda sac-religious, but have you considered using
Lee's pre-mixed kiln wash?

I used to have kiln wash problems like you are describing on my
shelves. I tried every recipe in the archives. Some would last one
firing, some would last maybe 10, but all flaked eventually. Tried
Laguna & Aardvark's regular mix too.

Then I bought some Lee's Super Incredible Kiln Wash from Axner. I know
it's outrageously expensive (relatively) but what's your time worth? It
seems to last indefinitely at cone 6- like 100 firings or more. The only
time I have to re-coat is when glaze gets on the shelf.

http://www.axner.com/axner/equipment/lees-kiln-wash.php

Best, DMH

David Martin Hershey
DMH Studio + Design
2629 Manhattan Ave # 137
Hermosa Beach CA USA
90254-2447
studio: 310.379.6890
dmhsd at dmhstudio dot com
http://www.dmhstudio.com
http://www.dmhstudio.etsy.com

Patti Petit on tue 17 jun 08


I'm with Carol. Same kiln wash problem. I've tried making mine according to various Clayart formula and also used purchased kiln wash. If the shelf won't take it, it won't take either wash. Thanks for the question, Carol.
Patti in NE GA

http://www.runningrabbitpottery.com

Larry Kruzan on wed 18 jun 08


-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Carole Fox
Sent: Tuesday, June 17, 2008 11:09 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: [CLAYART] Kiln shelf won't retain kiln wash

I have one kiln shelf that won't retain kiln wash.

------------snip-------------------

Hi Carole,

What kind of shelf is it?

Carole Fox on wed 18 jun 08


Larry - The material looks like my other shelves, which are cordierite.
However, there is nothing on the shelf to indicate, and I bought this one
separately a couple of years ago to replace a broken one. Based on the
price I paid and the appearance, I think this one must also be cordierite.
I am firing ^5-^7 electric, but kiln wash flakes off this one shelf in
bisque firing to ^04 as well.

Thanks,
Carole

-----Original Message-----
From: owner-clayart@lsv.ceramics.org
[mailto:owner-clayart@lsv.ceramics.org]On Behalf Of Larry Kruzan
Sent: Wednesday, June 18, 2008 8:58 AM
To: 'Clayart'
Subject: RE: [CLAYART] Kiln shelf won't retain kiln wash

-----Original Message-----
From: Clayart [mailto:CLAYART@LSV.CERAMICS.ORG] On Behalf Of Carole Fox
Sent: Tuesday, June 17, 2008 11:09 AM
To: CLAYART@LSV.CERAMICS.ORG
Subject: [CLAYART] Kiln shelf won't retain kiln wash

I have one kiln shelf that won't retain kiln wash.

------------snip-------------------

Hi Carole,

What kind of shelf is it?

Earl Krueger on wed 18 jun 08


What's the purpose of kiln wash?

If it's to keep glaze drips and pots from
sticking to the shelf, and if the kiln wash
doesn't stick then maybe the glaze and
pots won't stick either.

In other words,maybe you don't need it.

I'd probably put a little dab of glaze on
a spot of the shelf without kiln wash and
see how difficult (easy) it is to get off after
firing.

Earl Krueger
Elmira, OR, usa