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## calculating cat kiln volume

### sam bucus on thu 9 dec 10

Hi,=3D20
=3DA0
Regarding kiln volume I have been working with the equation=3D20
[(4/3 H x 1/2W) x L]/ 1728 =3D3D cubic feet in a cat kiln.

If I use that with the Peg Udall kiln measurements as printed in the Jack T=
=3D
roy=3DA0book=3DA0I usually get 41 cu ft.=3D20
=3DA0
However, the measurements on the=3DA0second page of the designs include 2 w=
id=3D
ths of brick (one on=3DA0either=3DA0side going with the draft direction)=3D=
A0that=3D
really is=3DA0just wall brick not kiln space. It also does not include the=
4=3D
.5" of brick=3DA0where the bagwall would be. If I include the bag wall area=
i=3D
n the equation, which could be stackable area and is certainly kiln space, =
=3D
I get 44.25 cu ft.=3DA0But if I subtract the=3DA02 brick widths on either s=
ide =3D
that decreases the=3DA0width of the kiln to 31.5" and I get only 31 cu ft.=
=3DA0=3D
Thats a big decrease in kiln volume, like 30%. Is the true volume of that k=
=3D
iln 31 cubic=3DA0feet or 44??
=3DA0
Thanks,=3D20
Sam=3D0A=3D0A=3D0A

### Michael Wendt on fri 10 dec 10

Calculus is a great tool for figuring this out normally but
I prefer
graph paper.
Get a bead chain like those used for light pulls.
Tape a piece of graph paper to a firm vertical surface like
the
refrigerator.
Select a scale that will fit the graph paper.
Using the squares as a guide, mark the inside base of the
kiln at
the top of the paper and the height inside at the bottom.
With a helper, hang the bead chain holding it at the two end
points
and gradually pay it out until it just lines up with the
bottom mark.
Use a pen or pencil to mark the arc described by the chain
(a true catenary arch).
Now turn it upright.
Lay out various shelf configurations of actual shelves you
will use
to see how many will fit and what those various positions
will give
you in stackable volume considering their length into the
plane
of the paper (which represents the front to back size of the
kiln).
You can even photocopy various configurations and ring bind
them
as future reference to save time planning the load stack and
also
plan to make pots in the optimum amounts and sizes to fill
Regards,
Michael Wendt

### Craig Edwards on sat 11 dec 10

Hey Michael and All: Great idea! I popped the image of the kiln into
Photoshop and snapped a grid. Same sort of thing, easy to manipulate also.
From snowin and blowin Minnesota
Cheers
--
Make Good Pots
~Craig
New London MN
http://woodfiredpottery.blogspot.com/

On Fri, Dec 10, 2010 at 10:28 AM, Michael Wendt wrote:

> Calculus is a great tool for figuring this out normally but
> I prefer
> graph paper.
> Get a bead chain like those used for light pulls.
> Tape a piece of graph paper to a firm vertical surface like
> the
> refrigerator.
> Select a scale that will fit the graph paper.
> Using the squares as a guide, mark the inside base of the
> kiln at
> the top of the paper and the height inside at the bottom.
> With a helper, hang the bead chain holding it at the two end
> points
> and gradually pay it out until it just lines up with the
> bottom mark.
> Use a pen or pencil to mark the arc described by the chain
> (a true catenary arch).
> Now turn it upright.
> Lay out various shelf configurations of actual shelves you
> will use
> to see how many will fit and what those various positions
> will give
> you in stackable volume considering their length into the
> plane
> of the paper (which represents the front to back size of the
> kiln).
> You can even photocopy various configurations and ring bind
> them
> as future reference to save time planning the load stack and
> also
> plan to make pots in the optimum amounts and sizes to fill