Lynn Barnwell on mon 31 may 04
Kathi,
When I got a new kiln my supplier shipped the Thorley shelves with it. I
had 4 of 8 crack at almost center of the long side. These fit in a 12
sided electric kiln that I fire to cone 6. This happened in my first bisque
and I had set a 4 hour preheat to make sure my pieces were dry so there was
no rapid heat rise to crack the new shelves. My supplier took care of them
for me but I have been leery of them since then.
Hinkle Creek Pottery
Corinth, Mississippi
Lynn Barnwell on wed 2 jun 04
Kathi,
When I got a new kiln my supplier shipped the Thorley shelves with it. I
had 4 of 8 crack at almost center of the long side. These fit in a 12
sided electric kiln that I fire to cone 6. This happened in my first bisque
and I had set a 4 hour preheat to make sure my pieces were dry so there was
no rapid heat rise to crack the new shelves. My supplier took care of them
for me but I have been leery of them since then.
Lynn Barnwell
Hinkle Creek Pottery
Corinth, Mississippi
Kathi LeSueur on thu 3 jun 04
wendtpot@LEWISTON.COM wrote:
>I use Thorley shelves exclusively.
>Thorley shelves have always cracked.
>Everything fails.......
>
>Once they have been to cone 10
>a few times, I have never seen one
>crack in use unless it was in shear.
>By shear, I mean, the posts are not
>in a straight column, one above another.>>>
>
I understand what you are saying about Thorley shelves and my
experience is similar to a degree. Small edge cracks. I also have never
had one fail. However, this is a different situation. These cracks run
half way through the shelves in exactly the same place of every shelf
and at the same angle. You could stack all of the shelves and line those
cracks right up. That has never happened before. And I find myself
reluctant to use shelves that have split half way through.
But, the most disturbing thing to me is Laguna's refusal to return my
calls. I will not be ordering anything from them again.
Kathi
>
>
>
>
Michael Wendt on thu 3 jun 04
I use Thorley shelves exclusively.
Thorley shelves have always cracked.
Everything fails.
I went to LA, California every year
for countless years and each time, I
went to South Gate to the Thorley
plant and picked up new shelves.
They were never subjected to the
rough handling of shipping.
About 1/3 would crack almost
at once. I use those for bisque work.
In the 31 years I have used Thorley
shelves, I have built up a supply of
nearly 60 cracked shelves, some of
which have seen constant use since
the late 70s.
Once they have been to cone 10
a few times, I have never seen one
crack in use unless it was in shear.
By shear, I mean, the posts are not
in a straight column, one above another.
Bob Haecker, the old CE plant manager
showed me photos he had received
over the years from people who complained
bitterly about cracked or warped shelves
when they had huge shear loads evident
in their photos.
I would very much doubt that Laguna
changed anything when they acquired the
Thorley plant. Thorley makes very good
kiln shelves! Some just crack first time
out.
Perhaps it would be a good idea to run
the new shelves a little slower the first few
times they are used.
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave
Lewiston, Idaho 83501
USA
wendtpot@lewiston.com
www.wendtpottery.com
Don Kopyscinski on fri 4 jun 04
Kathy wrote:
<every shelf
and at the same angle.>>
I have seen this happen when 4 posts have been used to support a shelf. Did
you use 3 or 4 posts?
No Cracking Cracking in Half Down Center
____________________ ____________________
[ X X] [ X
]
[ ] [
]
\ / \ X X
/
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\______X_______ / \ ______X_____ /
Regards,
Don Kopyscinski
Bear Hills Pottery
Newtown, CT
Kathi LeSueur on fri 4 jun 04
DonKopy@AOL.COM wrote:
>Kathy wrote:
><>every shelf
>and at the same angle.>>
>
>I have seen this happen when 4 posts have been used to support a shelf. Did
>you use 3 or 4 posts?>>>>>>>
>
>
>
>
Three posts. I am following the same stacking procedures as when I first
bought Thorley shelves in 1976. My kiln procedures are the same for the
past fifteen years. I've never had this problem.
Kathi
Michael Wendt on fri 4 jun 04
Kathi,
Since you are using good post placement,
it could well be the shelves were defective.
I only mentioned the cracking with mine
because I run loads so fast, I would be
surprised if any other shelves could survive
(3 1/2 hrs from red heat to cone 10).
Be sure to let us know how Laguna resolves this.
Good luck,
Regards,
Michael Wendt
Wendt Pottery
2729 Clearwater Ave
Lewiston, Idaho 83501
USA
wendtpot@lewiston.com
www.wendtpottery.com
Kathi wrote:
Three posts. I am following the same stacking procedures as when I first
bought Thorley shelves in 1976. My kiln procedures are the same for the
past fifteen years. I've never had this problem.
Kathi
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