Kiln Mods - Need validation

Paul Tarlow · Post by **Paul Tarlow** » Tue Apr 15, 2003 11:54 pm

I've posted in the past about having problems with particulate falling from the fire brick lid of my kiln. I coated the lid with a refractory coating and that work for a while...but is now cracking and stuff is falling again.

I've received lots of advice (thanks) and settled on a plan to:

1) remove the lid elements

2) attach a fiber board (Duraboard HD) lining to the inside if the lid with to-be-determined stainless steel fasteners

3) replace the lid elements with new elements in quartz tubes attached to the surface of the fiber board lined lid (with stainless steel wire through the lid ?)

I would greatly appreciate feedback/advice from those of you more familliar with kiln building (that would be just about everyone).

Thanks,
Paul

Brad Walker · Post by **Brad Walker** » Wed Apr 16, 2003 1:18 am

One of the things that Larry Fielder stressed in the kiln-building course I took at Carol Craiglow's a while back was that you should never rigidize the lid of a kiln. His view was that the rigidizer eventually gives way and causes even worse flaking and cracking.

Larry felt that an HD lining (as you describe) was a good idea; he also promoted just a fiber blanket lining (with no rigidizer). I think either will work for you.

You can use quartz tubes (elements inside) or quartz or high temp porcelain rods in the middle of the elements. Stainless steel wire should work fine to secure the tubes or rods -- you can use stainless welding rod if you want.

Bob · Post by **Bob** » Wed Apr 16, 2003 10:03 am

Paul,

I know how frustrating it is to have gunge from the lid fall on the surface of the glass. I have a couple of Evenheats with the cement parging on the lid. I find that the lid drops material in cycles. It will be bad for a couple of months and then be OK for a long time. I guess it is sort of going through puberty. Any chance you can last out a cycle?

I also vacuum the element channels on the lid periodically. I don't put the nozzle directly on the lid but separate it from the lid with my fingers. I also am very careful and lift or lower the lid slowly when I open or close the lid when making observations during fusing.

These "techniques" might be purely placebo. I may also be currying favour with the kiln gods for being nice to the beast and they might be cutting me some slack.

Option two is to go to sandblasting all your work.... I call the sandblaster my eraser.

I guess the point that I am making is that you might be able to avoid the repair. Just some guesses and a bit of voodoo.

Cheers,

Bob

Jacques Bordeleau · Post by **Jacques Bordeleau** » Wed Apr 16, 2003 10:05 am

The inside top surface of my big box has a 1/4" layer of HD board (backed by 3" of MD block. It doesn't seem to drop a lot of garbage on glass, but is not totally perfect. I hold them in place with stainless bolts and fender washers...works great. I use quartz tubes with the elements inside and strongly recommend that method to anyone considering it. I got a huge roll of stainless wire from Norco for $10 (made for wire feed welders). I use the wire 2 ways to secure the quartz tubes....I attach it to the existing stainless bolts previously mentioned, or as needed elsewhere, I drill throught the top of my kiln and loop it around....works just great. You are on the right track. Just be really certain that the support wire cannot touch any exposed element....obviously!

Regards, Jacques Bordeleau