little spots of crud on my work

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Dianne Van de Carr
Posts: 18
Joined: Sun Mar 09, 2003 3:43 pm
Location: Carmichael, CA
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little spots of crud on my work

Post by Dianne Van de Carr »

Let me give a bit of background information on my kiln. It is a fiber lined 20" square kiln. About 6 months ago, I had a controller relay fail. When I checked the kiln in the morning (yeah, I know, never go to bed with the kiln firing) it was very hot and the elements had sagged into my work, luckily shorting them out before causing a fire. Of course everything was ruined. Glass had run off the shelf.....what a mess! I bought new elements and my brother in law instaled them. We replaced the damaged fire brick on the bottom of the kiln and threw away the shelf. He felt it wasn't necessary to reline the kiln even tho the sides and top had gotten quite firm and "crunchy". Well, the kiln worked. I got another relay. All was well with the world. HOWEVER, I began getting little fiberous looking spots on my work. So, I did research and coated the top and elements (Big mistake on the elements when they got hot chunks of ITC dropped onto my work. I had to clean them off with a dental pick. Very tedious!) with ITC 100 and also ITC 296A. Well it got better, but lately the spots are back. The top still looks fine. Could it be from the crunchy sides? Should I reline my kiln? Could it be that convection currents are picking up little pieces of fiber during the firing and they are landing in my work? Help!
Dianne VdC
Tony Smith
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Joined: Sun Mar 09, 2003 5:59 pm
Location: Massachusetts, USA
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Post by Tony Smith »

Dianne,

It sounds like you should use coarse sandpaper or a sanding screen on the sides to knock off the bigger chunks and then coat with ITC. Did you sand the top before coating? That should get you down to fiber that hasn't been overfired and still has some binder holding the ceramic in place.

It'll be a little messy, maybe a good job to do outside on a nice day. Wear a respirator and eye protection and use a shop vac to collect as much of the dust as possible. Open the windows if you are working indoors.

Good luck.
The tightrope between being strange and being creative is too narrow to walk without occasionally landing on both sides..." Scott Berkun
Dianne Van de Carr
Posts: 18
Joined: Sun Mar 09, 2003 3:43 pm
Location: Carmichael, CA
Contact:

Post by Dianne Van de Carr »

Dear Tony,
It would have been a good idea to sand down the sides before coating with ITC. I didn't think of it. Oh well! The top doesn't seem to be the problem. The coating is hardened and when I brush over it, nothing falls off, that is what made me suspect the sides which are uncoated and crunchy. At this point I am thinking I should gut the kiln and reline it. These specks are driving me nuts!
Thanks for your suggestion. Of course, I will work safely.
Dianne
Tony Smith
Posts: 1037
Joined: Sun Mar 09, 2003 5:59 pm
Location: Massachusetts, USA
Contact:

Post by Tony Smith »

Dianne,

I have no doubt that you will work safely. The problem is that many people don't know that breathing dust from any source is not healthy.

Good luck.

Tony
The tightrope between being strange and being creative is too narrow to walk without occasionally landing on both sides..." Scott Berkun
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