Friday, May 31, 2013

Collapsing kiln posts: Ideas?

My friend Kim Medeiros and I are stumped as to what caused the splintering of three of the posts in her kiln yesterday. So I thought I'd try some blogger crowd-sourcing. 
Here are the facts: Kim has been firing to cone 10 with these posts in her Olympic updraft kiln for 15 years. Never a problem. (They were bought from Sheffield Pottery in western Mass. I've emailed Sheffield, but have had no response yet.) When she opened her kiln Thursday, one side of the stack was tilted ominously. Reaching the bottom layer, she found all three support posts tilted and splintered at the bottom, as you see in the photos.
It seems to us that if a prop was going to give way after 15 years it would happen one at a time. Or, perhaps, one in one part of the kiln and one in another. But all three on the same shelf strikes us both as a clue ... but a clue to what? We have no idea. Stacking was the same as usual, with heavier pots in the center of the stack, lighter ones to the outside. 
It seemed an ordinary firing other than the collapsing posts. Any ideas? Let me know.


8 comments:

Dennis Allen said...

Beats the heck out of me. Freakishly high tides??? Planetary misalignment?
Gravitational vortex??

Ashley Morrow said...

just wondering if there were any witness cones on that level?
I would be very tempted to swap out the old and get some new posts. They are fairly inexpensive considering what could potentially be lost.

Hollis Engley said...

Dennis, I hadn't thought of any of those ... she does live near the water ...
Not a bad idea, Ashley. They're pretty cheap. Would still like an idea of how they collapsed like that.

Tracey Broome said...

Hey Hollis, you may remember a few rants on my blog about Olympic and kiln posts splintering, kiln shelves cracking at ^10. If you call Olympic they are no help at all and will accuse you of being in error. I ended up calling the owner an asshole, told him to go f himself and slammed the phone down. They are the worst company I have ever dealt with! My theory is that the posts are just not made to withstand that much heat, mine cracked on me the first time I ever took them to 10. You can do a search on my blog, maybe enter Olymic in the search box and see my photos.
I finally got to talk to the owner of the company that made the kiln posts, he was awesome and sent me a huge box of new, round posts that are fantastic. I'm afraid Olympic won't help, unless hey have changed their ways. I even had an employee of the company sending me personal emails, telling me how the employees there were mistreated, it was all a really bad experience!
One other thought might be moisture, since she lives near water.....

Tracey Broome said...

Dec 11, 16, 23- 2009
Are the dates on my blog posts about Olympic, my kiln post photos look much the same as yours.
Sheffield might be better to deal with than Axner, where I got my kiln. Axner just referred me to Olympic and did noting to help me..... I would call the post manufacturer if you can find out who that it is.
I really think they start to disintegrate at really high heat level, why else would it be all of them at once? Mine was the very same, bottom shelf all at once, tilted kiln shelf.... Ugh, good luck!

June Perry said...

My first thought was maybe moisture. Did they get wet at some point? The one post looks like it was sitting on the edge. If that's the case, the weight of the shelves above resting only one corner corner could have caused that break. I can't see what's going on with that other post.
I'd suggest buying some new posts. If these lasted 15 years, why risk a kiln load of work being lost if there's so inherent flaw in the posts that will cause them, over time, to disintegrate.

Kings Creek Pottery said...

That is bizarre! I have no insight for you..but very interesting to hear Tracey's feedback/info. Sounds to me like she is onto something...

Hollis Engley said...

Thanks, all. I think there's something in what everyone says. (Except maybe Dennis's high tide and planetary misalignment ideas ... ) And Tracey, I well remember your altercation with the people at Olympic. I'm guessing they still don't send you a Christmas card. We may be going to the supplier in western Mass. this week. We'll take the posts and see if they have any answers. I do think new posts might be a good idea.