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simple kiln design question

updated wed 8 feb 06

 

Vince Pitelka on mon 6 feb 06


> Polygonal top loading kilns that I have used have always used roofs
> (and floors) of mortared IFB. I am curious about some properties of
> insulating fibreboard. Would it be strong enough to support K23 IFB
> 4.5" thick over a span of 18 in x 18 in? I know it would be
> considerably more expensive, but there is one advantage to this method
> that attracts me.

Mark -
Suitability of fiber products for hotface depends on their individual
rating. But fiberboard would not support the IFB over time, and I don't
understand why you would even want to do it that way. 4.5" of IFB will
provide plenty of insulation, and as long as you stagger the joints and
mortar them together with APGreen Greenpatch 421 (still being made and sold
by whoever bought out APGreen) or some other appropriate high-duty mortar,
and put a clamping band around the edge, you will have a lid as sturdy as
any commercially-made kiln.
Good luck -
- Vince

Vince Pitelka
Appalachian Center for Craft, Tennessee Technological University
Smithville TN 37166, 615/597-6801 x111
vpitelka@dtccom.net, wpitelka@tntech.edu
http://iweb.tntech.edu/wpitelka/
http://www.tntech.edu/craftcenter/

mtigges@NOSPAM.SHAW.CA on mon 6 feb 06


On Mon, Feb 06, 2006 at 08:56:56PM -0600, Vince Pitelka wrote:
> >Polygonal top loading kilns that I have used have always used roofs
> >(and floors) of mortared IFB. I am curious about some properties of
> >insulating fibreboard. Would it be strong enough to support K23 IFB
> >4.5" thick over a span of 18 in x 18 in? I know it would be
> >considerably more expensive, but there is one advantage to this method
> >that attracts me.
>
> Mark -
> Suitability of fiber products for hotface depends on their individual
> rating. But fiberboard would not support the IFB over time, and I don't
> understand why you would even want to do it that way. 4.5" of IFB will
> provide plenty of insulation, and as long as you stagger the joints and
> mortar them together with APGreen Greenpatch 421 (still being made and sold
> by whoever bought out APGreen) or some other appropriate high-duty mortar,
> and put a clamping band around the edge, you will have a lid as sturdy as
> any commercially-made kiln.
> Good luck -
> - Vince
>

I've received answers to my question which was borne of my ignorance,
and I am thankfull for them. The sole reason that I thought of it is
that I like the idea of easy repair. I want to have a design that
facilitates very easy repair. That ultimately means no mortar, and
not having threaded bricks would also help. So, for the roof
(admittedly, not as vulnerable as the floor) I was wondering what I
might support it with such that mortar was unneccesary.

I guess there's a reason that the majority of kilns are all built in
the same way!

Mark.