Subject: casting pewter

From: [email-masked] (Jacqueline Hamilton)
Date: Mon, 15 Aug 1994 13:34:55 GMT

I'm wanting to get some info on casting a pewter piece.  I have a small
flat original I want to make into a pin.  Can pewter be cast into a
silicon rubber mold, or should I use something else?  I want to retain
the detail on the piece.  Can I melt the pewter with a torch and crucible?
I know pewter has a relatively low melting point, so I'd assume so.

Anyway, thanks for any info.

-j.
--
-jackie hamilton
[email-masked]
---------------------------------------------------------
http://fohnix.metronet.com/HomePages/kira/newhome.html

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From: [email-masked] (Barry Workman)
Date: Wed, 17 Aug 1994 06:21:46 GMT

>-j.

I dunno about silicon standing up to the temp of pewter but
pewter is nothing more than glorified solder.  Tin/lead mostly
although I'm probably a little off and we'll get lots of reaction
to that.  As such it is meltable on a stovetop in a small pan as
a crucible,  like a #2 or #3 cast iron frying pan.  Torches just
melt it faster is all.  You can probably make a decent mold that
will stand up to several pours from crystobolite or even plaster
of paris.  Crystobolite is jewelers and dentists mold material used
for lost wax casting.  There is a book available from Lindsay
Publications, -- see FAQ -- on casting objects of beauty it 
seems to be a reasonable piece although I've not read the book,
Lindsays descriptions always tell you exactly what to expect.
Don't assume there is more.
-- 
    - Barry Workman

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From: [email-masked] (James Kirkpatrick)
Date: 17 Aug 94 08:24:11 MDT

In article <[email-masked]>,
[email-masked] (Barry Workman) writes:
|>[email-masked] (Jacqueline Hamilton) writes:
|>
|>>I'm wanting to get some info on casting a pewter piece.  I have a small
|>>flat original I want to make into a pin.  Can pewter be cast into a
|>>silicon rubber mold, or should I use something else?
|>
|>I dunno about silicon standing up to the temp of pewter

First, a minor correction:  silicon is the brittle glassy stuff they make
semiconductors out of.  Silicone is the rubbery stuff they make glue
and breast implants out of, and is the material under discussion.
It would be interesting to meet a lady with silicon breasts!  :-)

This is getting to be a frequently asked question!

OK, now, as long as we're discussing silicone rubber made specifically
for use as a metal-casting mold material, here's what somebody else
said just last February:

 The rubber will handle pewter, solder, woods metal, and probably pure lead
 and tin.  It is unlikely that it can handle the temperatures required for
 brass & copper (in blacksmit terms, these melt at a "white" heat).

 Rule of thumb:  if the molten metal GLOWS, it's probably too hot for silicone
                rubber.

Someone else wrote (discussing rings):

 There are various methods, ranging from cuttlefish bone through
 vulcanising machines, but I'd recommend RTV silicone rubber
 (room-temperature vulcanizing, that is).  It's easy to use even the first
 time, not unreasonably toxic, as cheap as anything else in one-ring
 quantities, and you can run off many very good copies with ease once you've
 got the mold.

 It can be obtained in a small can at a plastics or jewelry-supply place,
 or many of the FAQ catalogs will carry it.  I get mine from Polytek in New
 Jersey, which I forget if is in the FAQ - it's a rubber/plastic supply
 house with good prices, every kind of mold material back to gelatine(!),
 in any quantity, and catalogs that double as instruction manuals and tip
 sheets - (908)534-5990.  Excellent, excellent sculpture source...but I
 digress.

 Information about how to use RTV rubber is in various jewelry handbooks (I
 began with _Creative Casting_ by Sharr Choate; it's OK; or I can talk
 about small sculpture castings, but that may be more or less relevant.

So yes, silicone molds can stand pewter heat.

Jim

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From: [email-masked] (John O. Kopf)
Date: 17 Aug 1994 19:48:48 GMT

> pewter is nothing more than glorified solder.  Tin/lead mostly

Pewter is nominally a tin-copper alloy (typically 90% tin, 10% copper).  It
often has additional elements, such as Antimony, which help the molten flow
properties, etc.

JK

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From: kaminsky@comp..uark.edu (Hank Kaminsky)
Date: 26 Sep 1994 00:26:43 GMT

>>>I'm wanting to get some info on casting a pewter piece.  Can pewter be cast

I have cast pewter (Tin 92.5%, antimony 7.5%) into ordinary silicone 
caulk molds and had good results for a small number of castings (less 
than 10, say) Just smear the stuff on a well sealed and lightly paste 
waxed original and when 1/4" of the stuff has cured back it up with a 
plaster mother mold. Then pour the pewter.

Hank
--
Hank Kaminsky ([email-masked])
543 Assembly Rd. (Home) 501-443-2077
641 West 6th St. (Studio) 501-442-5805
Fayetteville AR 72701

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From: [email-masked] (Vance Bass)
Date: 26 Sep 1994 10:13:00 -0400

In article <[email-masked]> kaminsky@comp..uark.edu (Hank Kaminsky) writes:
>than 10, say) . . .

Where do you get lead-free pweter?  I don't seem to be asking in the right
places, since all the hobby shops I've tried have either looked blank when
I asked or have responded "I think I can find a source--let me look around".
The one guy who was knowledgeable about soft metal casting is a black-powder
shooter, and casts his own bullets as well as miniature figures.  He uses
lead wheel-balancing weights and warns of the lead-poisoning danger.

So, where are the sources of lead-free casting pewter?
-- 
=-=-=All the above are OFFICIAL POSITIONS and are ABSOLUTELY TRUE!=-=-=
Vance Bass                    	  	  Reply-to: [email-masked]
"It don't mean a thing if it ain't got that certain je ne sais quoi."
						   -- Peter Schickele

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From: [email-masked] (Barry Workman)
Date: Thu, 29 Sep 1994 23:04:26 GMT

>Dow Corning makes a red silicon rubber specifically for casting pewter. The 
>bad news is to makle perfect molds the rubber must be evacuated using 28" of 
>mercury pressure. However, the mould is good for up to 100 pours depending on 
>design and sharp edges.

>Best melting is done using a cast iron bowl on a kitchen stove using a 
>suitable flux to remove dross.

Uh, the newest Harbor Freight catalog has a 29.5" vacuum pump in it
for cheap...
-- 
    - Barry Workman