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press molds

updated wed 22 mar 06

 

Amy Y on sat 2 aug 97

Hi,
I saw the note about high relief press molds. Now, I'm not doing
extremely large pieces, but I do sometimes use press mold techniques for
making ornaments. One thing that I've found to work extremely well for
releasing the clay from the smallest of mold parts is non-stick cooking
spray (Like PAM). Squirt some on the mold and the clay falls right
out. Now your clay will develop some nasty molds in the drying process,
but they burn off in the firing.

---Amy
Potter, In Dallas, PA

Susan Benson on fri 5 sep 97

In a message dated 97-08-02 10:09:55 EDT, ayanalu@epix.net (Amy Y) writes:

<< One thing that I've found to work extremely well for
releasing the clay from the smallest of mold parts is non-stick cooking
spray (Like PAM). Squirt some on the mold and the clay falls right
out >>
.....................snip..........................

I've experimented with different release agents, and what works best for me
is putting a medium dusting of cornstarch based baby powder on the surface of
the clay before pressing it into the mold (coating or dusting the mold
doesn't work nearly so well. Talc based baby powder works well also, but
leaves a residue afteer firing, cornstarch, of course, burns right away.
WD40 is also sometimes useful.

Susan

Eric Lindgren on mon 8 sep 97

------------------
I use wooden press molds, with white flour on the mold as the release
agent. I like a hard white unbleached organic...

=80 It was likely at 6:54 AM -0400, on or about 9/5/97, Susan Benson sent:

=82 ----------------------------Original message----------------------------
=82 In a message dated 97-08-02 10:09:55 EDT, ayanalu=40epix.net (Amy Y) =
writes:
=82
=82 =3C=3C One thing that I've found to work extremely well for
=82 releasing the clay from the smallest of mold parts is non-stick cooking
=82 spray (Like PAM). Squirt some on the mold and the clay falls right
=82 out =3E=3E
=82 ....................snip..........................
=82
=82 I've experimented with different release agents, and what works best for=
me
=82 is putting a medium dusting of cornstarch based baby powder on the =
surface of
=82 the clay before pressing it into the mold (coating or dusting the mold
=82 doesn't work nearly so well. Talc based baby powder works well also, =
but
=82 leaves a residue afteer firing, cornstarch, of course, burns right away.
=82 WD40 is also sometimes useful.
=82
=82 Susan

Susan Schultz on wed 30 sep 98

I was taught (70's) to use a brushing of flint on deep press molds to
assist in release -obviously not a good idea with current knowledge
of silica problems. Is there anything safe that can be used for a
quicker release? I am rereading Donald Frith's book and find no
reference to anything but waiting until the clay pulls away from
the sides of the plaster, which greatly cuts down on the number of
times you can use the press mold in a day. I am impatient!
Thanks-
Susan Schultz

Bob Wicks on thu 1 oct 98

Try Talc. It works good.

Bob

Kris Baum on thu 1 oct 98

This is probably heresy, but ...

I have had success in releasing deep-relief tiles molded in plaster
by setting the molds "end-on" into the breeze from a fan. This
orientation has the air flowing over the front and back of the mold.
The result is that the back of the tile dries quite
quickly, and tends to warp a little as it pulls away from the mold.
The entire tile ends up releasing from the mold much more quickly
than if the filled molds are just left to dry in the ambient air.
The slight warping has actually been a benefit for me because it
ensures that the center of the tile is slightly concave to the edges
- it eliminates the nasty curling up at the edges that I am sometimes
plagued with. As I remove the tile from a mold, I replace the empty
mold in front of the stream of air from the fan so that it has a
chance to dry a little bit as I am unmolding subsequent tiles -
therefore I get a kind of continuous rotation of filling molds,
emptying molds, drying molds, filling molds, etc. This method has
worked well for me in production situations. Of course, I usually
make at least 3-5 identical molds, depending on the size of the job,
to speed up the process, as well.

> ----------------------------Original message----------------------------
> I was taught (70's) to use a brushing of flint on deep press molds to
> assist in release -obviously not a good idea with current knowledge
> of silica problems. Is there anything safe that can be used for a
> quicker release? I am rereading Donald Frith's book and find no
> reference to anything but waiting until the clay pulls away from
> the sides of the plaster, which greatly cuts down on the number of
> times you can use the press mold in a day. I am impatient!
> Thanks-
> Susan Schultz
>
Kris Baum
Shubunkin Pottery
Gaithersburg, MD
USA

mailto:shubunki@erols.com

Dee Clay on fri 2 oct 98

Hi Susan,
I haven't worked with plaster press molds but I use Pam (veggie spray) on
metal and plastic molds. Works great. Use sparingly and pieces slide out
whenever you're ready.
Diane in Miami

Brian Crocker on fri 2 oct 98

------------------
Talc Susan and a mask, use it often but the mask is a must,
Kind regards,
Brian Crocker.
4 Erica Street, Tea Tree Gully, S.A. 5091
AUSTRALIA.
=7B e.mail address =7D crocker=40picknowl.com.au
phone-fax 08 8264 4136

----------
=3E ----------------------------Original message----------------------------
=3E I was taught (70's) to use a brushing of flint on deep press molds to
=3E assist in release -obviously not a good idea with current knowledge
=3E of silica problems. Is there anything safe that can be used for a
=3E quicker release? I am rereading Donald Frith's book and find no
=3E reference to anything but waiting until the clay pulls away from
=3E the sides of the plaster, which greatly cuts down on the number of
=3E times you can use the press mold in a day. I am impatient=21
=3E Thanks-
=3E Susan Schultz

wrightspot on fri 2 oct 98

----------
> From: Susan Schultz
> To: CLAYART@LSV.UKY.EDU
> Subject: Re: Press molds
> Date: Wednesday, September 30, 1998 11:13 PM
>
> ----------------------------Original message----------------------------
> I was taught (70's) to use a brushing of flint on deep press molds to
> assist in release -obviously not a good idea with current knowledge
> of silica problems. Is there anything safe that can be used for a
> quicker release? I am rereading Donald Frith's book and find no
> reference to anything but waiting until the clay pulls away from
> the sides of the plaster, which greatly cuts down on the number of
> times you can use the press mold in a day. I am impatient!
> Thanks-
> Susan Schultz

Hi Susan,
We use WD40 or RP7 sprayed onto the mold before use and that helps greatly
in releasing the clay in our North Star hand operated press mold. Our
method doesn't necessarily relate to your problem but it may be worth
giving it a try. If your mold is deep though, you would probably need to
allow the clay to firm up a little before removing the item, so you may
have to practise patience!
Denise.

gambaru on fri 2 oct 98

A suggestion: If you have bats or another surface made of a formica type
material then dampen it slightly and put the exposed clay surface of your
mold on it, with a bit a movement or twisting action. Let it sit for a few
minutes and it should hold the clay to the surface as you pull off the mold.
The variables in the moisture content of clay in mold and moisture in the
mold will change the amount of time it has to sit. MB
-----Original Message-----
From: Susan Schultz
To: CLAYART@LSV.UKY.EDU
Date: Wednesday, September 30, 1998 9:12 AM
Subject: Re: Press molds


>----------------------------Original message----------------------------
>I was taught (70's) to use a brushing of flint on deep press molds to
>assist in release -obviously not a good idea with current knowledge
>of silica problems. Is there anything safe that can be used for a
>quicker release? I am rereading Donald Frith's book and find no
>reference to anything but waiting until the clay pulls away from
>the sides of the plaster, which greatly cuts down on the number of
>times you can use the press mold in a day. I am impatient!
>Thanks-
>Susan Schultz
>

Cindy on sat 3 oct 98

Susan,

I sometimes dust my hand-made press molds with flour. It works for me.

Cindy Strnad
Earthen Vessels
Custer, SD
USA http://blackhills-info.com/a/cindys/menu.htm

Timothy Dean Malm on sat 3 oct 98

powdered corn starch dusted on to the surface of the mold works very well.
Yes, I'm referring to the same stuff that is used for thickening
gravy.Cheers, Tim Malm in Seattle, WA.

Corinne Null on sat 3 oct 98


After reading in the Ceramics Monthly suppliment Pottery Illustrated, I've
learned to put a thin piece of plastic over the mold, and then putting the
clay
over that. After letting it set up for part of a day, it is easily removed
from the form and then the plastic peeled off.

Corinne


At 08:35 AM 10/2/98 -0400, you wrote:
>----------------------------Original message----------------------------
>Hi Susan,
>I haven't worked with plaster press molds but I use Pam (veggie spray) on
>metal and plastic molds. Works great. Use sparingly and pieces slide out
>whenever you're ready.
>Diane in Miami
>
Corinne Null
Bedford, NH
USA

null@mediaone.net
ICQ #18593487

Bob Wicks on tue 13 oct 98

Susan:
I have been using a compressor and the air seems to do the job very quickly.
I just point the nozzle right at the seams and you would be surprised how well
it works.


Bob

Val on mon 9 apr 01


Does anyone know where I can obtain press molds...I am looking for
small flowers etc....in Canada?....I live in Ontairo...
Thanks
Val Mann w.w.
Memory Box Artist
Val@tlaz.com
I have never been poor only broke.Being poor is a state of mind. Being broke
is only a temporary situation.
YESTERDAY'S CHILD CERAMIC & ART STUDIO
LONDON Ont. Canada

WHOLESALER OF BISQUE
SEMINARS/CLASSES: Ceramics, decorative art, oils and Bob Ross oils, Watercolour, one stroke, screen painting and
pen & Ink, oil rouging
http://www.tlaz.com/scans

icq #1592406
fax-(519) 649-1025,phone (519)649-0119

GaryBear on mon 19 nov 01


Hi, Can anyone out there suggest a source where one can find press =
molds or small molds suitable for accents?
Thanks,
Gary Finfrock

Debbie Jestin on tue 20 nov 01


Hi Gary, Make them. Find what you'd like to have and make a mold out of
either clay or plaster. If you use clay bisque it. Another option is check
out ceramic molds on EBay, sometimes there are small molds that can be used.

Joyce Lee on tue 20 nov 01


This is in response to the request for a place to buy press molds. When =
I began with clay ..... or at least began thinking about clay and =
pottery ... I found my way to a publication called Ceramics Magazine. =
Having been informed that an excellent potters pub existed named =
Ceramics Monthly, seeing the CM on a list, and occasionally being a =
"dive right in without first checking depth of water" sort, I subscribed =
to the wrong (for me) CM for a full two years. What I'm leading to is =
that in Ceramics Magazine there are many ads for all types of molds. I =
even ordered a few ...... from strips of very tiny ones which could be =
handy for press molding .... to a gigantic pumpkin mold that I have to =
lift in sections.... expensive (I think it was $45.00 U.S. currency) and =
never used. =20

If you'd like addresses for possible catalogs, please post me off list. =
My collection of CMag is now five years old but the information could =
still be current.

Joyce
In the Mojave marveling at the breadth and depth of the clay world =
......

Susan Conners on tue 20 nov 01


In a message dated 11/19/01 10:06:35 PM Central Standard Time,
garybear@SHADRACH.NET writes:


> Hi, Can anyone out there suggest a source where one can find press molds
> or small molds suitable for accents?
>

CASCO Molds has a large selection of press molds. Address and phone from a
1999 ceramic show receipt is: 347 Sam Houston, Mineral Springs, TX 76067,
phone (940) 325-1195. Hope this helps, Susan

Debbie Jestin on tue 20 nov 01


Hi Gary, I've made molds of frogs, lizards, dragonflys, flowers,shells, etc.
You can get plastic reptiles, etc, at a Dollar store or small molds at
Micheal's,( or you can sculpt your own, bisque it, and then use it to press
into the clay block to make a mold of). To make a press mold form a block of
clay about the size of the object you want about 1" thick, coat the frog
with Vaseline or cooking spray and press into the clay, let the mold dry
very well and bisque.

Leava Major on tue 20 nov 01


Gary,it is hard to find the press molds already made but it is easy to make your own.
I use super sculpey,an oven fired polymer clay found at craft stores.To make the molds,I keep
an eye
out for interesting brass charms,old jewelry pieces,dollhouse miniatures,
etc....

Form a thickish,maybe 3/4 inch thick even small slab of sculpey.Impress your object into the
sculpey
to the depth you want the clay piece to be but deeper to allow for shrinkage.


follow the directions on the sculpey box to bake.I form the molds on a glazed ceramic tile
and bake on it in the toaster oven.If you do more than the occasional piece you will need a
garge
sale oven dedicated to the process as the residue inside the oven may transfer to food
later....

if you make the mold too thin,it will break easily when you push into it.....so make it
thicker than
you think is needed.......
plaster molds of course release easily but these polymer molds need a release agent.
I use white flour dusted in every 3rd impression or so.You can of course make plaster molds
from
your molded pieces from the clay molds.But I am plaster challenged and
these give instant gratification and last for hundreds of uses.......

I have photos of some of my pieces (link in sigline) to give you an idea.......
Leava



Hi, Can anyone out there suggest a source where one can find press molds or small molds
suitable for accents?
Thanks,
Gary Finfrock

--

Leava Major,Honeysuckle Hollow,Handcrafted Pottery,Paper and Soaps
FRAGMENTS image,word tiles & buttons for stampers,collage artists and crafters
http://albums.photopoint.com/j/AlbumIndex?u=785087&a=9304438
PINS for soapers,stampers,scrappers,fiber artists
http://albums.photopoint.com/j/AlbumIndex?u=785087&a=11535017&f=0
SOAPTILES.stoneware soapdishes,lightbulb rings AND NEW FOOT FISHIES
http://albums.photopoint.com/j/AlbumIndex?u=785087&a=13055994&amp;amp;f=0
MARKERS...garden markers and signs CUSTOM ORDERS IN CLAY WELCOME

Marcia Selsor on sun 19 mar 06


On Mar 19, 2006, at 12:50 AM, lela martens wrote:

> I'm actually interested in using the wallboard for a mold because
>> I've tried the pink foamboard and found that it "sheds" tiny pink
>> bits into
>> the slab and also doesn't release the slab very well. Have others
>> found
>> ways around these two obstacles?
>
> You could put a fabric barrier over the foamboard, between
> it and the clay...cheesecloth, thin jersey,
> some such.
> Lela
>
> _
My teacher, Bill Daley, used styrofoam molds 35 years ago. He also
put a thin skin of
plaster on the surface. He said it helped speed up the drying and
gave a clean surface .
I do the same thing today. Sure makes light weight molds. These are
mainly hump molds.

Marcia Selsor
http://marciaselsor.com

Sandy Miller on mon 20 mar 06


A few months back I tried the builders insulation foam in a can.
Spray your form with WD 40 or any release agent then spray away.
The stuff expands. Way cool, like a science project gone wild.
When I do it again I will put my form in a box to keep everything
even and nicer shape for staking.
Sandy Miller
www.sandymillerpottery.com

Nan Thurn Kitchens on tue 21 mar 06


Marcia wrote.....My teacher, Bill Daley, used styrofoam molds 35 years ago.
He also
put a thin skin of plaster on the surface. He said it helped speed up the
drying and
gave a clean surface. I do the same thing today.
Marcia Selsor
http://marciaselsor.com

Marcia,
You've got my interest, would you please elaborate on how to make these
molds?
Specifically, I have questions on how the plaster adheres....

It was great to see the clayart family in Portland.
Like a family reunion, never enough time to connect with
everyone.
I've got the dreaded Red boa cold bug too. Yech.
Glad it wasn't bird flu.
Strike that thought.

Nan Thurn Kitchens
Architectural Clayworks
Box 371070
Key Largo Florida 33037
305-451-9885

Marcia Selsor on tue 21 mar 06


Hi Nan,

Bill sawed thick styrofoam..sometimes 6" thick. We had a hot wire in
the industrial design shop,
but I think he sawed his by hand. Then refined a shape with a sur-
form tool.
Then after he was satisfied with the form, he put a thin coat of
paster on it. Sanded where needed.
The plaster sticks to styrofoam. I have done this with the white and
the blue styrofoam.
I can get "anal" about sanding. I don't think it needs to be that
smooth.

Marcia Selsor
http://marciaselsor.com


On Mar 21, 2006, at 12:39 PM, Nan Thurn Kitchens wrote:

> Marcia wrote.....My teacher, Bill Daley, used styrofoam molds 35
> years ago.
> He also
> put a thin skin of plaster on the surface. He said it helped speed
> up the
> drying and
> gave a clean surface. I do the same thing today.
> Marcia Selsor
> http://marciaselsor.com
>
> Marcia,
> You've got my interest, would you please elaborate on how to make
> these
> molds?
> Specifically, I have questions on how the plaster adheres....
>
> It was great to see the clayart family in Portland.
> Like a family reunion, never enough time to connect with
> everyone.
> I've got the dreaded Red boa cold bug too. Yech.
> Glad it wasn't bird flu.
> Strike that thought.
>
> Nan Thurn Kitchens
> Architectural Clayworks
> Box 371070
> Key Largo Florida 33037
> 305-451-9885

Elizabeth Priddy on tue 21 mar 06


The way I make plaster covered styrofoam forms
is to use the pre plastered strips of cheesecloth
that they use to make casts and free sculpture.
If you soak them in water for a minute or so, they
soften and your spread them over the styrofoam shape.
It adds strength to the mold as the plaster is clinging
to the cloth and the plaster and so willnot flake off.
It sets up really hard.

I actually like the texture of the cheese cloth, so I
just leave it, but if you don't want a fabric texture,
you can smear it with a rubber rib and make it smooth.

Regarding that texture, if you make your own strips,
out of any textile you choose, you just drag them through
regular mixed plaster and apply them. lace makes
a pretty texture, so would eyelet or corderoy.

The most useful form I ever made is half a 3 inch styrofoam
ball covered with plaster cloth. It can be used to structure
a pinch pot, to tap a concave foot onto a leather hard piece,
just the right size to drape a handle over to stiffen up, a
sizer for lid galleries (and then you can use the form to
shape a freeform lid, it will offer support so you can texture
all you like)...

If you go to my website, that round earthenware pot was made
using this styro/plaster ball. The bottom of it was thrown and
the ball used to check the diameter of the lip. Then the top
was made over the ball and then joined to the bottom when
they were both leather hard.

http://www.elizabethpriddy.com

e

Nan Thurn Kitchens wrote:
Marcia wrote.....My teacher, Bill Daley, used styrofoam molds 35 years ago.
He also
put a thin skin of plaster on the surface. He said it helped speed up the
drying and
gave a clean surface. I do the same thing today.
Marcia Selsor
http://marciaselsor.com

Marcia,
You've got my interest, would you please elaborate on how to make these
molds?
Specifically, I have questions on how the plaster adheres....


Elizabeth Priddy

Beaufort, NC - USA
http://www.elizabethpriddy.com

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