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you can repair plaster molds the traditonal way

updated sun 22 feb 04

 

Ivor and Olive Lewis on thu 19 feb 04


Dear Friends,
When teaching Carving my students prepared their own plaster blocks.
Now I always found there was at least one hamfisted young chap who
would try to rush the job and remove far more than was needed with a
heavy blow. Which provided an opportunity to explain how to repair
broken plaster, be it for the work in hand or when filling cracks in
walls.
The time honoured way is to soak the broken parts of the mould in
water until it is thoroughly wet, then prepare a quantity of "Killed
Plaster" from equal volumes of water and plaster to act as the
adhesive. Be sure if you ever use this method to add the plaster to
the water.
Mix the plaster well then apply it to the wet surfaces with a wet
brush. Then bring both part together. Do not try to dress fracture
surfaces but be sure to align the edges and faces. Strap the parts
together and leave to set up. Do not disturb until the plaster has
dried and is fully hardened.
Not the sort of technique to use if you are in a hurry, but it can be
used to repair fractures, dents or scrapes.
Best regards,
Ivor Lewis. Redhill, South Australia

----- Original Message -----
From: "smart"
To:
Sent: Wednesday, 18 February 2004 5:01
Subject: Re: Can you repair plaster on molds?


> Dear Rachel,
>
> If you just need to use it a couple more times you can repair it
with
> cyanoacrylate glue for porous materials (like loctite super glue if
this
> product is available in your country). This glue can bond wet
materials as
> plaster. The main thing in this repair is to apply the glue
punctually with
> no continuous layer, in order to facilitate the water absorption by
the
> plaster. This repair is temporary but it will give you the
possibility to
> use again your cracked mold.
>
> Cordialement, Denis
>
> Smart.Conseil
> Le site Fran=E7ais d=E9di=E9 aux passionn=E9s de c=E9ramique
> El sitio Franc=E9s dedic=F3 a amantes de cer=E1mica
> The French site dedicated to ceramics lovers
> smart2000@wanadoo.fr
> http://perso.wanadoo.fr/smart2000/
> (Langue Fran=E7aise par d=E9faut : Tutoiement =E0 la "Qu=E9b=E9coise")
> ----- Original Message -----
> From: "Edouard Bastarache Inc."
> To: "Smart.Conseil"
> Sent: Tuesday, February 17, 2004 6:21 PM
> Subject: Fw: Can you repair plaster on molds?
>
>
> > Peux-tu l'aider.
> >
> >
> >
> >
> > "Ils sont fous ces quebecois"
> > Edouard Bastarache
> > Irreductible Quebecois
> > Indomitable Quebeker
> > Sorel-Tracy
> > Quebec
> > edouardb@sorel-tracy.qc.ca
> > http://sorel-tracy.qc.ca/~edouardb/
> > http://perso.wanadoo.fr/smart2000/index.htm
> > http://www.digitalfire.com/education/toxicity/
> >
> > ----- Original Message -----
> > From: "SierraEarthWorks"
> > To:
> > Sent: Monday, February 16, 2004 8:44 PM
> > Subject: Can you repair plaster on molds?
> >
> >
> > Hello Everyone!
> > I just want to know if you can repair molds. I have a mold
that I
> > would absolutely die if it were to become unusable, at least I
need to use
> > it a couple more times. It has cracked, but it could easily be
glued back
> > together. Is this possible? Do they make some special mending
material for
> > this purpose? Even if it is temporary, that would be o.k.. Thanks,
> > Rachel
> >
> >
>
______________________________________________________________________
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> >
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> > melpots@pclink.com.
> >
> >
>
>
______________________________________________________________________
________
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>
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melpots@pclink.com.

J. B. Clauson on thu 19 feb 04


What the heck is "killed" plaster? How do you go about killing it?

Jan C.

Kathy Forer on fri 20 feb 04


On 2/19/04 11:43 AM, "J. B. Clauson" wrote:

> What the heck is "killed" plaster? How do you go about killing it?

Either by drowning it or strangling it. Details in the archive.

:)

Mildred Herot on fri 20 feb 04


With reference to "killed plaster", my understanding is that you normally
add plaster to water until the plaster rides on the top and then mix it.
When you want to "kill" the plaster, you mix it immediately as you put in
into water. Mildred Herot
----- Original Message -----
From: "Kathy Forer"
To:
Sent: Friday, February 20, 2004 3:46 AM
Subject: Re: You can repair plaster molds the traditonal way


> On 2/19/04 11:43 AM, "J. B. Clauson" wrote:
>
> > What the heck is "killed" plaster? How do you go about killing it?
>
> Either by drowning it or strangling it. Details in the archive.
>
> :)
>
>
____________________________________________________________________________
__
> 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.

Kathy Forer on fri 20 feb 04


on 2/20/04 12:13 PM, Mildred Herot at milhero@COMCAST.NET wrote:

> With reference to "killed plaster", my understanding is that you normally
> add plaster to water until the plaster rides on the top and then mix it.
> When you want to "kill" the plaster, you mix it immediately as you put in
> into water. Mildred Herot

You can also keep mixing plaster through the point at which it sets. It
becomes a pasty putty and can be molded. Theoretically it can be workable
for 24 hours, vid. .

The advantage of "killed" plaster is that it will dry to the same hardness
and color as the surrounding area, not appear as a dried patch. Remember to
flush the base area thoroughly with water before patching so the set plaster
won't absorb water from the added material.

Another way of getting rid of air bubble pinholes is to, again, wet the area
thoroughly, then using a small paint brush dip a wet brush into dry plaster
and then drop that into the airhole. Freshly killed, overworked plaster
seems to blend in the best.

Kathy Forer
http: //www.kforer.com

Ivor and Olive Lewis on sat 21 feb 04


Dear MIldred Herot,
My instructions, which I believe come from antiquity, are to pour
plaster powder into an excess of water, allow the powder to slake and
then mix. That is what I demonstrated to my students and it does
effect a satisfactory repair.
You might find the original in Vasari. I think he talks about the
problems Cellini had with plaster moulds for his bronze casting.
Best regards,
Ivor Lewis. Redhill, South Australia