CraigD on thu 11 jan 01
"First, supposedly, Orton cones are 25 to 35 degrees Farenheit margin of
>error due to impurities in contained in the material used to make them =
and
>"loose" quality control in the manufacturing process"
I do not believe the figures mentioned above are any near accurate. If =
memeory serves, there was a post not too far back, from Tim at Orton, I =
think he stated that the margin of error was only +/- 3 or 4 degrees F.
Ask David H., he rolls his own and I am willing to bet his homemade =
cones are a hell of a lot more reliable than 25 to 35* F..
David Hendley on fri 12 jan 01
Since my name was mentioned, and Tim Frederick hasn't
checked in, as I thought he would, I'll also agree that this
"25 to 35 degree F margin of error" in cones bit is totally false.
I think this misconception came from the discussion about
cones bending at different temperatures, depending on the
rate of temperature rise.
Cones are extremely consistent from batch to batch.
--
David Hendley
Maydelle, Texas
hendley@tyler.net
http://www.farmpots.com/
----- Original Message -----
From: CraigD
To:
Sent: Thursday, January 11, 2001 8:08 PM
Subject: Re: reliability of cones
"First, supposedly, Orton cones are 25 to 35 degrees Farenheit margin of
>error due to impurities in contained in the material used to make them and
>"loose" quality control in the manufacturing process"
I do not believe the figures mentioned above are any near accurate. If
memeory serves, there was a post not too far back, from Tim at Orton, I
think he stated that the margin of error was only +/- 3 or 4 degrees F.
Ask David H., he rolls his own and I am willing to bet his homemade cones
are a hell of a lot more reliable than 25 to 35* F..
____________________________________________________________________________
__
..
Janet Kaiser on sat 13 jan 01
Cones (made by any reputable manufacturer) are
probably the most reliable ceramic product on
the market. Have to be, otherwise generations of
potters would not have used them, especially in
the days when all the technical gizmos were
unheard of or beyond the means of small
producers and makers.
In addition to what has been said now and during
past discussions, surely 25 to 30 degrees
Fahrenheit is not going to make any difference
anyway? You will get that variation (and more)
between different parts of any reasonably sized
kiln.
25 to 30 deg. Celsius may make a teeny weeny
difference, but the glaze would have to be
terribly touchy. If that degree of precision is
absolutely essential, perhaps a mechanical
measurement system (cones) is not appropriate
anyway?
Just my tuppence worth!
Janet Kaiser
The Chapel of Art . Capel Celfyddyd
HOME OF THE INTERNATIONAL POTTERS' PATH
Criccieth LL52 0EA, GB-Wales Tel: (01766) 523570
E-mail: postbox@the-coa.org.uk
WEBSITE: http://www.the-coa.org.uk
----- Original Message -----
> Since my name was mentioned, and Tim Frederick
hasn't
> checked in, as I thought he would, I'll also
agree that this
> "25 to 35 degree F margin of error" in cones
bit is totally false.
> I think this misconception came from the
discussion about
> cones bending at different temperatures,
depending on the
> rate of temperature rise.
> Cones are extremely consistent from batch to
batch.
> --
> David Hendley
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