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soap molds

updated tue 14 mar 06

 

Kat on sun 12 mar 06


Hi guys,

I know this isn't really pottery related, but I'm running out of luck finding
inexpensive soap mold making material...it's for a tsunami relief project in SW
Thailand to make soap in the shapes of turtles, only I haven't a clue how to
make a soap mold. I'd like to not have to buy anything like RTV rubber or
liquid vinyl as the budget for the project is quite small, and I have to be able to
find the materials in rural Thailand. Does anyone know if you can use plaster
to make soap molds? Are they reusable? Can anyone think of anything else?

Thanks for your time, hope to hear back
Kat

L. P. Skeen on sun 12 mar 06


Kat,

In addition to making pots, I also have been making and selling handmade =
soaps for about 10 years. I don't think plaster will make a good soap =
mold. Part of the reason is that your mold needs to be waterproof. =
Part of the reason is that soap is poured at over 100*F and I don't know =
about the thermal shock properties of plaster. Part of the reason is =
that I don't think you want a film of plaster on your mold, and you =
would definitely get that.

Having said that, I have a contact here in the States who makes latex =
molds and she is a very generous person. I have to get back in touch w/ =
her and then I will hook y'all up. I know she makes a turtle mold that =
would be good for your purposes.

L
----- Original Message -----=20
From: Kat=20
I know this isn't really pottery related, but I'm running out of luck =
finding
inexpensive soap mold making material...it's for a tsunami relief =
project in SW
Thailand to make soap in the shapes of turtles, only I haven't a clue =
how to
make a soap mold. I'd like to not have to buy anything like RTV =
rubber or
liquid vinyl as the budget for the project is quite small, and I have =
to be able to
find the materials in rural Thailand. Does anyone know if you can use =
plaster
to make soap molds? Are they reusable? Can anyone think of anything =
else?

Kathy Rhoades on sun 12 mar 06


Kat,
I've never used plaster of paris for soap molds. All the info that I have suggests something flexible so you can pop the soap out or something you can destroy like cardboard shapes so you can peel it off the soap. It also suggests plactic and stainless steal, glass and china. I have used cardboard boxes of various sizes, lined with wax paper (so I can reuse the box), to make larger bricks of soap that I can then cut into smaller squares, rectangles, or whatever shape I want after it has cured for a short time. Scraps of soap can then be remelted and used again or used to make balls of soap or flaked for washing clothing. Cans like tuna or pet food cans can be recycled and used again and again. If your soap won't pop out you have to pry it out of the molds and I'm not sure plaster will hold up to that, and if you are making lye soap, I dont' know if it will hold up to the sudden heat change when pouring the hot liquid into it. Anyhow, all these are great but you want turtles,

unless you can make something else. Also, pouring the hot liquid in small molds can be quite a task to get done before the soap mixture starts to firm up. Unless you aren't making lye soap. I hope this was somewhat helpful. A wonderful thing you are doing!!!!!!

Kathy from PA

Kat wrote:
Hi guys,

I know this isn't really pottery related, but I'm running out of luck finding
inexpensive soap mold making material...it's for a tsunami relief project in SW
Thailand to make soap in the shapes of turtles, only I haven't a clue how to
make a soap mold. I'd like to not have to buy anything like RTV rubber or
liquid vinyl as the budget for the project is quite small, and I have to be able to
find the materials in rural Thailand. Does anyone know if you can use plaster
to make soap molds? Are they reusable? Can anyone think of anything else?

Thanks for your time, hope to hear back
Kat

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mtigges@NOSPAM.SHAW.CA on sun 12 mar 06


On Sun, Mar 12, 2006 at 04:51:28AM -0500, Kat wrote:
> Hi guys,
>
> I know this isn't really pottery related, but I'm running out of luck finding
> inexpensive soap mold making material...it's for a tsunami relief project in SW
> Thailand to make soap in the shapes of turtles, only I haven't a clue how to
> make a soap mold. I'd like to not have to buy anything like RTV rubber or
> liquid vinyl as the budget for the project is quite small, and I have to be able to
> find the materials in rural Thailand. Does anyone know if you can use plaster
> to make soap molds? Are they reusable? Can anyone think of anything else?
>
> Thanks for your time, hope to hear back
> Kat
>

My wife is a soap maker. We combine our efforts and sell pottery and
soap at craft fairs.

I don't believe plaster is a good idea. Getting the soap out of the
mold is an issue. It's not like clay, it doesn't shrink. It won't
just pop out. The mold must be made of something that you can peel
off the soap. For the big blocks of soap from which bars get cut, we
use shower curtain material to line the mold.

For small shapes, like turtles, we use flexible ice cube trays. Of
course we are restricted to the shapes that you can purchase. I've
never seen turtles.

Pretty much the only solution that we have tried is liquid latex.

I fear that you are going to have a hard time doing this in rural
thailand without bringing the molds with you.

If you do use plaster I suspect that the soap will seep into the pores
and make it very difficult to remove (plus I suspect that the
unsaponified lye would eat the plaster quickly). You would have to
line the plaster with plastic cling film. But then of course it
becomes very difficult to get resolution on the detail of the form, you
will inevitably have wrinkles in the film that will show in the
finished soap. If your turtle shapes are not very detailed, that may
in fact be ok.

BTW, I will also caution you that making small pieces of soap is
difficult. The reason is that saponification must happen slowly.
Small pieces can cool too quickly stopping the reaction and you end up
with something that isn't soap. This word of caution though only
really applies if you are making (the ironically named) cold process
soap. If you are only melting and pouring, it's irrelevant,
everything should be fine.

Best of luck,

Mark.

Snail Scott on sun 12 mar 06


At 01:14 PM 3/12/2006 -0500, you wrote:
>...soap is poured at over 100*F and I don't know about the thermal shock
properties of plaster. Part of the reason is that I don't think you want a
film of plaster on your mold, and you would definitely get that...


I don't know diddly about soap, but plaster=20
molds are routinely used for wax, which is=20
often poured around 200=BAF. The wax doesn't=20
stick because the molds are kept saturated=20
with water.=20

-Snail

Lolli Cook on mon 13 mar 06



Hello


I make flexible molds with a material from smooth-on, I am sure it can be ordered from their website.  There are also lots of instructions diagrams availble there. they are focused on not only the indutrial user but artists in general. Latex is fine as well, much more inexpesive,    and you must let layers dry in between coats, (lengthy) a thin layer of 4 coats should be layered/thickened with latex soaked material (strips of rags) and baked with a plaster mother mold behind it.


Feel free to email me if you would like further info


Laura Lea "Lollipots" Cook


www.lollipots.ca










From:  mtigges@NOSPAM.SHAW.CA
Reply-To:  Clayart <CLAYART@LSV.CERAMICS.ORG>
To:  CLAYART@LSV.CERAMICS.ORG
Subject:  Re: soap molds
Date:  Sun, 12 Mar 2006 08:25:08 -0800
On Sun, Mar 12, 2006 at 04:51:28AM -0500, Kat wrote:
> Hi guys,
>
> I know this isn't really pottery related, but I'm running out of luck finding
> inexpensive soap mold making material...it's for a tsunami relief project in SW
> Thailand to make soap in the shapes of turtles, only I haven't a clue how to
> make a soap mold.  I'd like to not have to buy anything like RTV rubber or
> liquid vinyl as the budget for the project is quite small, and I have to be able to
> find the materials in rural Thailand.  Does anyone know if you can use
plaster
> to make soap molds?  Are they reusable?  Can anyone think of anything else?
>
> Thanks for your time, hope to hear back
> Kat
>

My wife is a soap maker.  We combine our efforts and sell pottery and
soap at craft fairs.

I don't believe plaster is a good idea.  Getting the soap out of the
mold is an issue.  It's not like clay, it doesn't shrink.  It won't
just pop out.  The mold must be made of something that you can peel
off the soap.  For the big blocks of soap from which bars get cut, we
use shower curtain material to line the mold.

For small shapes, like turtles, we use flexible ice cube trays.  Of
course we are restricted to the shapes that you can purchase.  I've
never seen turtles.

Pretty much the
only solution that we have tried is liquid latex.

I fear that you are going to have a hard time doing this in rural
thailand without bringing the molds with you.

If you do use plaster I suspect that the soap will seep into the pores
and make it very difficult to remove (plus I suspect that the
unsaponified lye would eat the plaster quickly).  You would have to
line the plaster with plastic cling film.  But then of course it
becomes very difficult to get resolution on the detail of the form, you
will inevitably have wrinkles in the film that will show in the
finished soap.  If your turtle shapes are not very detailed, that may
in fact be ok.

BTW, I will also caution you that making small pieces of soap is
difficult.  The reason is that saponification must happen slowly.
Small pieces can cool too
quickly stopping the reaction and you end up
with something that isn't soap.  This word of caution though only
really applies if you are making (the ironically named) cold process
soap.  If you are only melting and pouring, it's irrelevant,
everything should be fine.

Best of luck,

Mark.

______________________________________________________________________________
Send postings to clayart@lsv.ceramics.org

You may look at the archives for the list or change your subscription
settings from http://www.ceramics.org/clayart/

Moderator of the list is Mel Jacobson who may be reached at melpots@pclink.com.