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throwing on canvas squares

updated mon 5 oct 98

 

Vince Pitelka on sun 20 sep 98

Regarding Geoff Walker's suggestion, this is a wonderful technique, which I
have used for thirty years. I have posted about it before, but here's a repeat.

Get some fairly heavy canvas, preferably at least 10 oz., and cut it into
squares, the smallest dimension of which should be at least an inch or two
larger than the base of the pots you plan to throw. Mix up a quart or so of
gritless slurry. If you are throwing porcelain or whiteware mix it from
kaolin or ball clay. If you are throwing stoneware, mix it from goldart.
Brush a thin coat of this slurry on both sides of each square, and allow
them to dry completely. When you are ready to throw a pot, smear a thin
coat of this slurry on the wheelhead, place a canvas square on top, and use
your flexible rubber rib to squeegee out from the center fo the square.
Turn on the wheel and continue to squeegee a bit more, spiraling out from
the center. The dry coat of slurry on the canvas will absorb the thin
remaining layer of slurry on the wheelhead, and it will attach the canvas
very firmly to the wheelhead. Do not use any slurry with sand or grog in
it, because the grit will act like little ball bearings, and the canvas will
often slide off the wheel. With gritless slurry, once you have attached a
canvas square to the wheelhead in this fashion, it is REALLY attached, and
you can throw on top of it in a normal fashion.

As Geoff Walker explained in his post, after you finish the pot, carefully
slide a wire between the canvas square and the wheelhead. I don't use this
technique for really large wares, and I would never use it for things which
would distort easily, such as large bowls, plates, and platters. A rigid
removeable bat always works better for those needs. For other forms, to
remove the pots from the wheel, I use one of those standard pointed
triangular concrete trowels, which you can get cheap at any gypo
building-materials store. Set the blade of the trowel flat on the
wheelhead, grab one corner of the canvas, pull it onto the trowel, lift the
pot over to the wareboard, pull if off the trowel onto the wareboard. You
never have to touch the pot, so this technique works especially well when
there is slip or other decoration which would preclude lifting the pot off
the wheel in a normal fashion. When the wares are leather hard, peel off
the canvas. If you do not intend to trim a foot, smooth off any burr around
the edge, and the bottom is finished.
- Vince

Vince Pitelka - vpitelka@DeKalb.net
Home 615/597-5376, work 615/597-6801, fax 615/597-6803
Appalachian Center for Crafts
Tennessee Technological University
1560 Craft Center Drive, Smithville TN 37166

Dannon Rhudy on sun 20 sep 98

Vince, I have used this from time to time since your last post
about it - it works great. Apparently I forgot the "brush-with-
slurry" part -- I just dredged mine in dry kaolin, and they have
worked fine ever since. I use them for large bowls/platters
letting the whole thing, canvas and all, dry on the bat,
because they will then come loose from the bat leaving a
completely flat base from which to trim a foot. I like plaster
bats for that purpose, too, but have found the canvas works
equally well.

Dannon Rhudy
potter@koyote.com

----------
> From: Vince Pitelka
> To: CLAYART@LSV.UKY.EDU
> Subject: Throwing on Canvas Squares
> Date: Sunday, September 20, 1998 9:20 PM
>
> ----------------------------Original message----------------------------
> Regarding Geoff Walker's suggestion, this is a wonderful technique, which
I
> have used for thirty years. I have posted about it before, but here's a
repeat.
>
> Get some fairly heavy canvas, preferably at least 10 oz., and cut it into
> squares, the smallest dimension of which should be at least an inch or
two
> larger than the base of the pots you plan to throw. Mix up a quart or so
of
> gritless slurry. If you are throwing porcelain or whiteware mix it from
> kaolin or ball clay. If you are throwing stoneware, mix it from goldart.
> Brush a thin coat of this slurry on both sides of each square, and allow
> them to dry completely. When you are ready to throw a pot, smear a thin
> coat of this slurry on the wheelhead, place a canvas square on top, and
use
> your flexible rubber rib to squeegee out from the center fo the square.
> Turn on the wheel and continue to squeegee a bit more, spiraling out from
> the center. The dry coat of slurry on the canvas will absorb the thin
> remaining layer of slurry on the wheelhead, and it will attach the canvas
> very firmly to the wheelhead. Do not use any slurry with sand or grog in
> it, because the grit will act like little ball bearings, and the canvas
will
> often slide off the wheel. With gritless slurry, once you have attached
a
> canvas square to the wheelhead in this fashion, it is REALLY attached,
and
> you can throw on top of it in a normal fashion.
>
> As Geoff Walker explained in his post, after you finish the pot,
carefully
> slide a wire between the canvas square and the wheelhead. I don't use
this
> technique for really large wares, and I would never use it for things
which
> would distort easily, such as large bowls, plates, and platters. A rigid
> removeable bat always works better for those needs. For other forms, to
> remove the pots from the wheel, I use one of those standard pointed
> triangular concrete trowels, which you can get cheap at any gypo
> building-materials store. Set the blade of the trowel flat on the
> wheelhead, grab one corner of the canvas, pull it onto the trowel, lift
the
> pot over to the wareboard, pull if off the trowel onto the wareboard.
You
> never have to touch the pot, so this technique works especially well when
> there is slip or other decoration which would preclude lifting the pot
off
> the wheel in a normal fashion. When the wares are leather hard, peel off
> the canvas. If you do not intend to trim a foot, smooth off any burr
around
> the edge, and the bottom is finished.
> - Vince
>
> Vince Pitelka - vpitelka@DeKalb.net
> Home 615/597-5376, work 615/597-6801, fax 615/597-6803
> Appalachian Center for Crafts
> Tennessee Technological University
> 1560 Craft Center Drive, Smithville TN 37166

Stephen Mills on fri 2 oct 98

I've been away for a week so I'm catching up, and this thread
caught my eye.
When I started production on a treadle Leach wheel I found that
Stopping every time to take a pot off was time wasting and
tiring, so pots had to come off a moving wheel. I did this
by trimming an undercut with a bamboo knife as the next to last
action on the pot, wiring under, then, having dried the tips of
2 fingers on each hand on my apron, lift the moving pot by the
undercut. It helps to lift one side fractionally before the
other.
Incidentally wiring off while the wheel is turning does a lot to
prevent "bowing up" in the centre of a large piece.

Steve
Bath
UK



In message , Vince Pitelka writes
>----------------------------Original message----------------------------
>Regarding Geoff Walker's suggestion, this is a wonderful technique, which I
>have used for thirty years. I have posted about it before, but here's a
>repeat.
>
>Get some fairly heavy canvas, preferably at least 10 oz., and cut it into
>squares, the smallest dimension of which should be at least an inch or two
>larger than the base of the pots you plan to throw. Mix up a quart or so of
>gritless slurry. If you are throwing porcelain or whiteware mix it from
>kaolin or ball clay. If you are throwing stoneware, mix it from goldart.
>Brush a thin coat of this slurry on both sides of each square, and allow
>them to dry completely. When you are ready to throw a pot, smear a thin
>coat of this slurry on the wheelhead, place a canvas square on top, and use
>your flexible rubber rib to squeegee out from the center fo the square.
>Turn on the wheel and continue to squeegee a bit more, spiraling out from
>the center. The dry coat of slurry on the canvas will absorb the thin
>remaining layer of slurry on the wheelhead, and it will attach the canvas
>very firmly to the wheelhead. Do not use any slurry with sand or grog in
>it, because the grit will act like little ball bearings, and the canvas will
>often slide off the wheel. With gritless slurry, once you have attached a
>canvas square to the wheelhead in this fashion, it is REALLY attached, and
>you can throw on top of it in a normal fashion.
>
>As Geoff Walker explained in his post, after you finish the pot, carefully
>slide a wire between the canvas square and the wheelhead. I don't use this
>technique for really large wares, and I would never use it for things which
>would distort easily, such as large bowls, plates, and platters. A rigid
>removeable bat always works better for those needs. For other forms, to
>remove the pots from the wheel, I use one of those standard pointed
>triangular concrete trowels, which you can get cheap at any gypo
>building-materials store. Set the blade of the trowel flat on the
>wheelhead, grab one corner of the canvas, pull it onto the trowel, lift the
>pot over to the wareboard, pull if off the trowel onto the wareboard. You
>never have to touch the pot, so this technique works especially well when
>there is slip or other decoration which would preclude lifting the pot off
>the wheel in a normal fashion. When the wares are leather hard, peel off
>the canvas. If you do not intend to trim a foot, smooth off any burr around
>the edge, and the bottom is finished.
>- Vince
>
>Vince Pitelka - vpitelka@DeKalb.net
>Home 615/597-5376, work 615/597-6801, fax 615/597-6803
>Appalachian Center for Crafts
>Tennessee Technological University
>1560 Craft Center Drive, Smithville TN 37166
>

--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk

Dwiggins, Sandra (NCI) on sat 3 oct 98

Stephen---you do this with plates and platters as well?
Sandy

-----Original Message-----
From: Stephen Mills [SMTP:stevemills@mudslinger.demon.co.uk]
Sent: Friday, October 02, 1998 8:43 AM
To: CLAYART@LSV.UKY.EDU
Subject: Re: Throwing on Canvas Squares

----------------------------Original message----------------------------
I've been away for a week so I'm catching up, and this thread
caught my eye.
When I started production on a treadle Leach wheel I found that
Stopping every time to take a pot off was time wasting and
tiring, so pots had to come off a moving wheel. I did this
by trimming an undercut with a bamboo knife as the next to last
action on the pot, wiring under, then, having dried the tips of
2 fingers on each hand on my apron, lift the moving pot by the
undercut. It helps to lift one side fractionally before the
other.
Incidentally wiring off while the wheel is turning does a lot to
prevent "bowing up" in the centre of a large piece.

Steve
Bath
UK



In message , Vince Pitelka writes
>----------------------------Original message----------------------------
>Regarding Geoff Walker's suggestion, this is a wonderful technique, which I
>have used for thirty years. I have posted about it before, but here's a
>repeat.
>
>Get some fairly heavy canvas, preferably at least 10 oz., and cut it into
>squares, the smallest dimension of which should be at least an inch or two
>larger than the base of the pots you plan to throw. Mix up a quart or so of
>gritless slurry. If you are throwing porcelain or whiteware mix it from
>kaolin or ball clay. If you are throwing stoneware, mix it from goldart.
>Brush a thin coat of this slurry on both sides of each square, and allow
>them to dry completely. When you are ready to throw a pot, smear a thin
>coat of this slurry on the wheelhead, place a canvas square on top, and use
>your flexible rubber rib to squeegee out from the center fo the square.
>Turn on the wheel and continue to squeegee a bit more, spiraling out from
>the center. The dry coat of slurry on the canvas will absorb the thin
>remaining layer of slurry on the wheelhead, and it will attach the canvas
>very firmly to the wheelhead. Do not use any slurry with sand or grog in
>it, because the grit will act like little ball bearings, and the canvas will
>often slide off the wheel. With gritless slurry, once you have attached a
>canvas square to the wheelhead in this fashion, it is REALLY attached, and
>you can throw on top of it in a normal fashion.
>
>As Geoff Walker explained in his post, after you finish the pot, carefully
>slide a wire between the canvas square and the wheelhead. I don't use this
>technique for really large wares, and I would never use it for things which
>would distort easily, such as large bowls, plates, and platters. A rigid
>removeable bat always works better for those needs. For other forms, to
>remove the pots from the wheel, I use one of those standard pointed
>triangular concrete trowels, which you can get cheap at any gypo
>building-materials store. Set the blade of the trowel flat on the
>wheelhead, grab one corner of the canvas, pull it onto the trowel, lift the
>pot over to the wareboard, pull if off the trowel onto the wareboard. You
>never have to touch the pot, so this technique works especially well when
>there is slip or other decoration which would preclude lifting the pot off
>the wheel in a normal fashion. When the wares are leather hard, peel off
>the canvas. If you do not intend to trim a foot, smooth off any burr around
>the edge, and the bottom is finished.
>- Vince
>
>Vince Pitelka - vpitelka@DeKalb.net
>Home 615/597-5376, work 615/597-6801, fax 615/597-6803
>Appalachian Center for Crafts
>Tennessee Technological University
>1560 Craft Center Drive, Smithville TN 37166
>

--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk

Stephen Mills on sun 4 oct 98


>----------------------------Original message----------------------------
>Stephen---you do this with plates and platters as well?
>Sandy
No, But when I started I couldn't afford Marine Plywood Batts (the only
waterproof material available at the time) so I learn't how to take
plates etc. straight off the wheelhead. This involved throwing the
plates initially fairly thick (I trim a medium deep foot on them) with
the aformentioned undercut, then "walking" my fingers, (palm up) under
from opposing sides about 1/3 in, lifting the plate up on (dryish) flat
hands in a sort of Vee shape. When on the board they always winged up
where I had lifted them but I flattened them off when it was trimming
time.
The clay consistancy was fairly soft, and I throw (usually) quickly with
the minimum number of movements. Throwing time on a 10" plate was about
50 seconds to 1 minute.

Steve

In message , Dwiggins, Sandra (NCI) writes

>
>-----Original Message-----
>From: Stephen Mills [SMTP:stevemills@mudslinger.demon.co.uk]
>Sent: Friday, October 02, 1998 8:43 AM
>To: CLAYART@LSV.UKY.EDU
>Subject: Re: Throwing on Canvas Squares
>
>----------------------------Original message----------------------------
>I've been away for a week so I'm catching up, and this thread
>caught my eye.
>When I started production on a treadle Leach wheel I found that
>Stopping every time to take a pot off was time wasting and
>tiring, so pots had to come off a moving wheel. I did this
>by trimming an undercut with a bamboo knife as the next to last
>action on the pot, wiring under, then, having dried the tips of
>2 fingers on each hand on my apron, lift the moving pot by the
>undercut. It helps to lift one side fractionally before the
>other.
>Incidentally wiring off while the wheel is turning does a lot to
>prevent "bowing up" in the centre of a large piece.
>
>Steve
>Bath
>UK
>
>
>
>In message , Vince Pitelka writes
>>----------------------------Original message----------------------------
>>Regarding Geoff Walker's suggestion, this is a wonderful technique, which I
>>have used for thirty years. I have posted about it before, but here's a
>>repeat.
>>
>>Get some fairly heavy canvas, preferably at least 10 oz., and cut it into
>>squares, the smallest dimension of which should be at least an inch or two
>>larger than the base of the pots you plan to throw. Mix up a quart or so of
>>gritless slurry. If you are throwing porcelain or whiteware mix it from
>>kaolin or ball clay. If you are throwing stoneware, mix it from goldart.
>>Brush a thin coat of this slurry on both sides of each square, and allow
>>them to dry completely. When you are ready to throw a pot, smear a thin
>>coat of this slurry on the wheelhead, place a canvas square on top, and use
>>your flexible rubber rib to squeegee out from the center fo the square.
>>Turn on the wheel and continue to squeegee a bit more, spiraling out from
>>the center. The dry coat of slurry on the canvas will absorb the thin
>>remaining layer of slurry on the wheelhead, and it will attach the canvas
>>very firmly to the wheelhead. Do not use any slurry with sand or grog in
>>it, because the grit will act like little ball bearings, and the canvas will
>>often slide off the wheel. With gritless slurry, once you have attached a
>>canvas square to the wheelhead in this fashion, it is REALLY attached, and
>>you can throw on top of it in a normal fashion.
>>
>>As Geoff Walker explained in his post, after you finish the pot, carefully
>>slide a wire between the canvas square and the wheelhead. I don't use this
>>technique for really large wares, and I would never use it for things which
>>would distort easily, such as large bowls, plates, and platters. A rigid
>>removeable bat always works better for those needs. For other forms, to
>>remove the pots from the wheel, I use one of those standard pointed
>>triangular concrete trowels, which you can get cheap at any gypo
>>building-materials store. Set the blade of the trowel flat on the
>>wheelhead, grab one corner of the canvas, pull it onto the trowel, lift the
>>pot over to the wareboard, pull if off the trowel onto the wareboard. You
>>never have to touch the pot, so this technique works especially well when
>>there is slip or other decoration which would preclude lifting the pot off
>>the wheel in a normal fashion. When the wares are leather hard, peel off
>>the canvas. If you do not intend to trim a foot, smooth off any burr around
>>the edge, and the bottom is finished.
>>- Vince
>>
>>Vince Pitelka - vpitelka@DeKalb.net
>>Home 615/597-5376, work 615/597-6801, fax 615/597-6803
>>Appalachian Center for Crafts
>>Tennessee Technological University
>>1560 Craft Center Drive, Smithville TN 37166
>>
>
>--
>Steve Mills
>Bath
>UK
>home e-mail: stevemills@mudslinger.demon.co.uk
>work e-mail: stevemills@bathpotters.demon.co.uk
>own website: http://www.mudslinger.demon.co.uk
>BPS website: http://www.bathpotters.demon.co.uk
>

--
Steve Mills
Bath
UK
home e-mail: stevemills@mudslinger.demon.co.uk
work e-mail: stevemills@bathpotters.demon.co.uk
own website: http://www.mudslinger.demon.co.uk
BPS website: http://www.bathpotters.demon.co.uk