Maria Elaine Lanza on wed 26 may 99
When altering a thrown teapot spout by cutting the tip to form a v-shape
edge... what degree of spin or turn do you make allowance for in the final
firing?... does the clay turn clockwise naturally because of its memory of
throwing?... if so, would you say for example, that the cut perhaps should
be no more than 10% to the left of center... bringing the v-shape edge
pretty much back in alignment? Hope I made myself clear on this... Thanks in
advance, Marie Elaine
Liz Willoughby on fri 28 may 99
Hello Marie,
The angle that the tip of the spout is cut depends on a few things. The
temperature that you fire too, i.e. the higher the temp. the more the
twist, the type of clay that you use, i.e.,porcelain spouts twist more than
stoneware, the speed of throwing, and the compression of the clay, inside
and out when throwing the spout. I use porc. C/10 R, and cut my spouts at
an angle say 5 o'clock with the spout facing you. Once I used another
porcelain body, and my spout twisted so much that it was almost facing
straight up! Experience is really the best teacher here with the clay and
temp. that you fire too.
Hope this helps,
Liz
>----------------------------Original message----------------------------
>When altering a thrown teapot spout by cutting the tip to form a v-shape
>edge... what degree of spin or turn do you make allowance for in the final
>firing?... does the clay turn clockwise naturally because of its memory of
>throwing?... if so, would you say for example, that the cut perhaps should
>be no more than 10% to the left of center... bringing the v-shape edge
>pretty much back in alignment? Hope I made myself clear on this... Thanks in
>advance, Marie Elaine
Liz Willoughby
R.R.# 1
2903 Shelter Valley Rd.
Grafton, Ontario
K0K 2G0
Canada
e-mail, lizwill@phc.igs.net
Martin Howard on sat 29 may 99
Another angle on this problem of Teapot Spouts is how to stop the drip.
On a recent UK TV show an inventor demonstrated how he has solved the
problem.
He just makes a lip designed to make any liquid left around the rime of
the spout collect in a V just under the spout and drop into the cup of
tea.
So simple really.
Now I am going to have a go and hope I am not breaking the law by
copying his idea.
Martin Howard
Webbs Cottage Pottery and Press
Woolpits Road, Great Saling
BRAINTREE
Essex CM7 5DZ
01371 850 423
araneajo@gn.apc.org
Alex Wilson on sat 29 may 99
Hello Marie, well it all depends on the nature of your clay and the amount of
torque applied when the spout was thrown. All-in-all a pretty imprecise
science, but a good result will come through trial and error, as in most
things.
Cheerio now,
Alex
Burt Cohen on sat 29 may 99
Maria Elaine Lanza wrote:
>
> ----------------------------Original message----------------------------
> When altering a thrown teapot spout by cutting the tip to form a v-shape
> edge... what degree of spin or turn do you make allowance for in the final
> firing?... does the clay turn clockwise naturally because of its memory of
> throwing?... if so, would you say for example, that the cut perhaps should
> be no more than 10% to the left of center... bringing the v-shape edge
> pretty much back in alignment? Hope I made myself clear on this... Thanks in
> advance, Marie Elaine
HI Marie-I would guess about 15 degrees from center would be right-If
you throw counterclockwise the direction most North Americans throw the
cut would be to the left of center-If you throw clockwise the way many
Asian potters throw the cut would be off to the right. -=Burt Cohen
orion on sat 29 may 99
I was also taught/told to anticipate thrown teapot spouts' "unwinding" or
"relaxing" when fired....
...BUT -- in (lots of!) practice, I've come to understand that the softer
your clay is, the less likely it is that this phenomenon will occur.
Often, I find, spouts don't "unwind" at all!
I suggest that, for each of your favorite clay bodies, you make a simple,
tall cylinder and a number (five or six) of "as-alike-as-possible" test
spouts. When the cylinder and spouts are set enough to handle, shape and
attach the test spouts to the cylinder at different "attitudes" (and trim
the spout tips in a variety of angles). I'd mount the first spout at a very
"true" right angle, then proceed with variations. Keep notes! Then dry,
bisque, glaze, and final fire the test piece(s) to full temperature. This
experiment will reveal just how much, and what kind of, spout changes to
anticipate -- IF ANY.
In my experience, the harder the clay, the more likely it is that you'll
suffer from "unwinding" or "clay memory" events. In any case, I don't think
anyone's theories or accounts on this subject can illuminate you better on
this subject than individual testing will!
Best of all to everyone!
Ellen Baker -- Glacier, WA
orion@telcomplus.net
Tom Wirt on sun 30 may 99
> In my experience, the harder the clay, the more likely it is that you'll
> suffer from "unwinding" or "clay memory" events. In any case, I don't
think
Folks.....the teapot spout isn't unwinding, or following its "memory"....it
is winding further. Take a look at the forces on the clay when you throw.
Assuming a counter clockwise wheel direction, the drag of your fingers is
pulling against that counterclockwise motion. This is the same as if you
were pulling a non turning piece in a clockwise direction. If the clay was
trying to return to the original position, it would twist counterclockwise.
So the clay is actually INCREASING the twist you start on the wheel. Now
will someone explain that?
Tom Wirt
John Baymore on mon 31 may 99
------------------
(clip)
I suggest that, for each of your favorite clay bodies, you make a simple,
tall cylinder and a number (five or six) of =22as-alike-as-possible=22 test
spouts. When the cylinder and spouts are set enough to handle, shape and
attach the test spouts to the cylinder at different =22attitudes=22 (and =
trim
the spout tips in a variety of angles). I'd mount the first spout at a
very
=22true=22 right angle, then proceed with variations. Keep notes=21 Then=
dry,
bisque, glaze, and final fire the test piece(s) to full temperature. This
experiment will reveal just how much, and what kind of, spout changes to
anticipate -- IF ANY.
(snip)
Excellent advice.
The one thing I'd add is to indicate on the body of the test pieces just
below the test spout on each the angle it was set at....a little visual
guide so you can look at it. Sort of a cilcel with a line within it
indicating the tip of the angle of the spout end.
BEst,
..................john
John Baymore
River Bend Pottery
22 Riverbend Way
Wilton, NH 03086 USA
603-654-2752
JBaymore=40compuserve.com
John.Baymore=40GSD-CO.COM
=22Earth, Water, and Fire climbing kiln firing workshop Aug. 20-29,1999=22
Mike Bailey on mon 31 may 99
In message , orion writes
>----------------------------Original message----------------------------
>I was also taught/told to anticipate thrown teapot spouts' "unwinding" or
>"relaxing" when fired....
>
Just to add some other observations to this topic. Of course, it's not
just teapot spouts that carry on 'winding' from clay memory. Some
plastic clays are prone to do this when making handled pots, such as
jugs and mugs. If you put the handle on straight, the top of the handle
twists in relation to the base of the handle - giving it a twist in the
firing.
Another unexpected result of this twisting came about when I made a
commemorative plate that was to be hung up on a wall. The plate had a
turned foot and so I put a couple of holes through the foot-ring -
thinking that tying a bit of wire or string through the holes would be a
good way of hanging it up. But, I'd forgotten the teapot spout syndrome.
The rim/dish and motto actually continued twisting (clockwise) in
relation to the base so that it was about 5 degrees out.
Cheers to all,
Mike Bailey
--
Mike Bailey
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