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kiln cracks

updated wed 29 sep 04

 

Ela Trent on thu 9 nov 00


Hi

I have a top loading kiln from Potterycrafts but it has developed a whole
series of cracks through both the lid and the base.

They have taken the kiln back to check it out and agree that the lid needs
changing but say that the cracks through the base are normal. They won’t
replace the kiln and have offered me a refund. I don’t think I want the
refund because then I’ll have to go through the hassle of buying a new kiln
etc etc. However, I’m not sure if I should accept my old cracked kiln back
- even though the lid will have been changed.

Can anyone help me decide what I should do? Do brand new kilns often get
cracks through the base so quickly? Should I be worried about the kiln
collapsing? Or should I trust Potterycrafts when they tell me that these
cracks are normal and nothing to worry about.

The cracks on the base follow round the cement between the bricks. The kiln
has been fired between 10 and 15 times. Personally I did not expect such
big cracks to appear so quickly.

If anyone can give me some help and advice on the above I would be really
grateful.

Thanks

Ela

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Cindy Strnad on thu 9 nov 00


Hi, Ela.

All my kilns have cracks in the bases. It's never been a problem for me.
I've never heard of Potterycrafts, but I'm impressed at their generosity in
offering you a refund for your kiln.

Cindy Strnad
Earthen Vessels Pottery
RR 1, Box 51
Custer, SD 57730
USA
earthenv@gwtc.net
http://www.earthenvesselssd.com

david self on thu 9 nov 00


Ela, I think you should consider that your kiln may be losing a lot of heat
due to the cracks. Resulting in less efficient firing and firing time. If
you went with a new kiln, there are still many uses for the old one. If
it's a small electric kiln, it could be used as a Raku kiln. You might also
consider keeping the kiln around for spare parts when needed....Good Luck!


>From: Ela Trent
>Reply-To: Ceramic Arts Discussion List
>To: CLAYART@LSV.CERAMICS.ORG
>Subject: Kiln cracks
>Date: Thu, 9 Nov 2000 13:35:38 GMT
>
>Hi
>
>I have a top loading kiln from Potterycrafts but it has developed a whole
>series of cracks through both the lid and the base.
>
>They have taken the kiln back to check it out and agree that the lid needs
>changing but say that the cracks through the base are normal. They won’t
>replace the kiln and have offered me a refund. I don’t think I want the
>refund because then I’ll have to go through the hassle of buying a new kiln
>etc etc. However, I’m not sure if I should accept my old cracked kiln back
>- even though the lid will have been changed.
>
>Can anyone help me decide what I should do? Do brand new kilns often get
>cracks through the base so quickly? Should I be worried about the kiln
>collapsing? Or should I trust Potterycrafts when they tell me that these
>cracks are normal and nothing to worry about.
>
>The cracks on the base follow round the cement between the bricks. The
>kiln
>has been fired between 10 and 15 times. Personally I did not expect such
>big cracks to appear so quickly.
>
>If anyone can give me some help and advice on the above I would be really
>grateful.
>
>Thanks
>
>Ela
>
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Mike Gordon on fri 10 nov 00


Hi,
Take the refund and buy another type of kiln. This one was probably
mishandled somewhere along the way. There shouldn't be any cracks
anywhere. Buy a Skutt. Mike Gordon

mel jacobson on sun 26 sep 04


they all crack.
they do it, it is natural.
bricks crack, the companies that make them
will tell you are lucky if they don't crack.

one of the most common silly complaints
that come across the desks of kiln manufacturers
is:

`i have a crack in the floor of my kiln, will it kill me?`

`no, just fire the gd kiln and forget about it.`

it is like a tiny scratch in your new car. does it still
run? yes, of course. it is cosmetic. but, most don't
have a clue about the difference. they don't understand
how kilns work, what they are made of, forces, energy of
heat, expansion and contraction.

`MY GOD, THERE IS A CRACK IN MY KILN...CALL SKUTT
NOW. GET ME A NEW KILN. NOW. OH, GOD, WILL THE
CAT DIE? DAN RATHER DID THIS, I KNOW., OH GOD, OH GOD.
THIS IS WORSE THAN TOM SAWYER.`

relax.

a few thoughts on cracks, kilns, shelves.
they crack and often it means nothing.
if you drill a hole at the end of the crack...it will
stop running. same for a kiln shelf. drill a hole
in the shelf, at the end of the crack. you can use that
shelf for another 50 years. just remember to stack your
shelves with three posts. keep one post under the crack
for your own peace of mind.

( industry uses shelves with many holes in them..they come
that way...perfect heat distribution in the kiln...no heat dams.
more firings are ruined because of stacking than firing.)

if you fill a crack with mortar, as i said yesterday...it will
just fall out, get bigger.
if you want a cosmetic cure...just fill with fiber and itc 100.
the crack is gone. even overhead. i itc fill the cracks in shelves.
never think of them again...can't see the crack.

i have had three shelves fail me since i began firing kilns 40 years
ago. they were all factory failed shelves. sued them, got all
new shelves. did not screw around. my old shelves were 27 years
old, not a crack...the new one's failed in three firings.
was it me? no, bad shelves.
got my money. small claims court. did not screw around.
did not whine once. just sent court papers.
not an argument at all.

in fact, your kiln will fire much better with cracks.
much better... cuzz you will get to work and stop being
a baby about your kiln. it is not walnut, hand made furniture.
it is a tool, and tools get dirty and crack. what is more beautiful
than a hammer handle that has been used for 80 years? it sure
ain't brittany spears. that is total ugly.
get on with your work.
mel



From:
Minnetonka, Minnesota, U.S.A.
web site: my.pclink.com/~melpots
or try: http://www.pclink.com/melpots
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val on mon 27 sep 04


Okay Mel thanks!...Your dry sense of humour (I refuse to think you are
being sarcastic, LOL) cracks me up!!! (a little play on words)...God it
has so many cracks in it but I will just keep using it...thanks
again...you made my life easier...
Have a good day
Val






they all crack.
they do it, it is natural.
bricks crack, the companies that make them
will tell you are lucky if they don't crack.

one of the most common silly complaints
that come across the desks of kiln manufacturers
is:

`i have a crack in the floor of my kiln, will it kill me?`

`no, just fire the gd kiln and forget about it.`

it is like a tiny scratch in your new car. does it still
run? yes, of course. it is cosmetic. but, most don't
have a clue about the difference. they don't understand
how kilns work, what they are made of, forces, energy of
heat, expansion and contraction.

`MY GOD, THERE IS A CRACK IN MY KILN...CALL SKUTT
NOW. GET ME A NEW KILN. NOW. OH, GOD, WILL THE
CAT DIE? DAN RATHER DID THIS, I KNOW., OH GOD, OH GOD.
THIS IS WORSE THAN TOM SAWYER.`

relax.

a few thoughts on cracks, kilns, shelves.
they crack and often it means nothing.
if you drill a hole at the end of the crack...it will
stop running. same for a kiln shelf. drill a hole
in the shelf, at the end of the crack. you can use that
shelf for another 50 years. just remember to stack your shelves with
three posts. keep one post under the crack for your own peace of mind.

( industry uses shelves with many holes in them..they come
that way...perfect heat distribution in the kiln...no heat dams. more
firings are ruined because of stacking than firing.)

if you fill a crack with mortar, as i said yesterday...it will just fall
out, get bigger. if you want a cosmetic cure...just fill with fiber and
itc 100. the crack is gone. even overhead. i itc fill the cracks in
shelves. never think of them again...can't see the crack.

i have had three shelves fail me since i began firing kilns 40 years
ago. they were all factory failed shelves. sued them, got all new
shelves. did not screw around. my old shelves were 27 years old, not a
crack...the new one's failed in three firings. was it me? no, bad
shelves. got my money. small claims court. did not screw around. did
not whine once. just sent court papers. not an argument at all.

in fact, your kiln will fire much better with cracks.
much better... cuzz you will get to work and stop being
a baby about your kiln. it is not walnut, hand made furniture. it is a
tool, and tools get dirty and crack. what is more beautiful than a
hammer handle that has been used for 80 years? it sure ain't brittany
spears. that is total ugly. get on with your work. mel




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Arnold Howard on mon 27 sep 04


I agree with Mel. The cracks close tightly during firing anyway, so they are
usually nothing to worry about. The cracks serve as expansion joints.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
arnoldhoward@att.net / www.paragonweb.com

From: "val"
> Okay Mel thanks!...Your dry sense of humour (I refuse to think you are
> being sarcastic, LOL) cracks me up!!! (a little play on words)...God it
> has so many cracks in it but I will just keep using it...thanks
> again...you made my life easier...

Kathy Forer on mon 27 sep 04


On Sep 26, 2004, at 9:56 AM, mel jacobson wrote:

> they all crack.
> they do it, it is natural.

What you say makes sense about cracks. What about small chunks missing,
should they be mortar 'glued' or repaired? Or 1" chips in front of
where the elements are? The elements won't fall out or anything, but
the surface is different and will the heating be significantly
different?

I'm inclined to leave it, warts and all, is that okay?

Kathy

Arnold Howard on tue 28 sep 04


Kathy, I agree about not repairing small chunks missing in a firebrick. It
will not affect the way the kiln fires.

Sincerely,

Arnold Howard
Paragon Industries, L.P., Mesquite, Texas USA
arnoldhoward@att.net / www.paragonweb.com

From: "Kathy Forer"
> > they all crack.
> > they do it, it is natural.
> What you say makes sense about cracks. What about small chunks missing,
> should they be mortar 'glued' or repaired? Or 1" chips in front of
> where the elements are? The elements won't fall out or anything, but
> the surface is different and will the heating be significantly
> different?
> I'm inclined to leave it, warts and all, is that okay?

Ron Roy on tue 28 sep 04


I agree with the opinion that cracks are not much of a problem - I also
think they can become a problem when they are open too much - as they all
will eventually.

The problem then becomes fast cooling and cool bottoms because air can move
up through the cracks during the firing and cooling.

Perhaps a false bottom at that point should be considered - perhaps some
fiber fax under a shelf? - or at least some extra fire bricks under the
floor to block cold air from flowing through from bottom to top?

RR


>> they all crack.
>> they do it, it is natural.
>
>What you say makes sense about cracks. What about small chunks missing,
>should they be mortar 'glued' or repaired? Or 1" chips in front of
>where the elements are? The elements won't fall out or anything, but
>the surface is different and will the heating be significantly
>different?
>
>I'm inclined to leave it, warts and all, is that okay?
>
>Kathy


Ron Roy
RR#4
15084 Little Lake Road
Brighton, Ontario
Canada
K0K 1H0
Phone: 613-475-9544
Fax: 613-475-3513