Subject: help? casting a silver piece

From: [email-masked] (Jacqueline Hamilton)
Date: Fri, 4 Mar 1994 15:33:45 GMT

I've sculpted a little horse piece that I'd really like to 
have made into a silver pin.  It's only about 1" square, relatively
flat with a flat back.  I considered trying to cast it myself but
I really don't know much about how to do it... I sent for the Rio
Grande catalog and they have that rubber for making molds but it
looks like it has to be vulcanized and I cant afford to pay $700
for one of their vulcanizing machines.  Am not sure what else could
be used for making a mold?

Looking for someone to make the mold/do castings for me... or else
more info on making molds and casting silver.  I thought about trying
with pewter first...  I have worked with the silicon RTV rubber before.

Any info is greatly appreciated.  Thanks!

-j.
[email-masked]

---

From: [email-masked] (Bathsheba Grossman)
Date: 4 Mar 1994 17:56:27 -0500

In article <[email-masked]>,
>Looking for someone to make the mold/do castings for me... or else

It isn't me, but I think you're in the right place.

In other news, what did you say to Rio Grande to make them send you a
catalog?  I've asked them four times in the last several years, written
and phone, and they say, coming right up, and don't send it, even though
I've ordered >$300 of stuff from other peoples' catalogs.  I've about had
it with them.

-Sheba

---

From: [email-masked] (Lord C)
Date: Fri, 4 Mar 1994 20:46:00 +0000

> with pewter first...  I have worked with the silicon RTV rubber before.

***Plaster of paris is usually made up into molds for casting ,use your
   piece as sample,use some peroleum jelly so you can get it out once its set

-- 

  |----------------------------------------------------|
    Lord Charvington of London
    resides at [email-masked]
    dont forget your e-mail address if you want a reply
  |----------------------------------------------------|

---

From: Larry Paul <[email-masked]>
Date: Sun, 6 Mar 94 20:08:56 -0500

Dear J,
 I'll be more than glad to help with casting or molding your pin.
You can reach me at my e-mail address or call my at:
                  Larry Paul Casting Co.,Inc.
                  740 Sansom St.
                  Phila. PA. 19106
                  (215) 928-1644
                  Fax (215) 574-1943
 
I cast Platinum, Gold, Sterling(2 kinds),and Silicon Brass.
I make RTV, Vulcanized Rubber(2 kinds), Dental, and Aluminum Molds.
Also Dies for Stamping.
My minimum order is one piece.
          Larry---- :{

---

From: [email-masked] (Dion Hollenbeck)
Date: Mon, 7 Mar 1994 22:04:29 GMT

>>>>> "Jacqueline" == Jacqueline Hamilton <[email-masked]> writes:

Jacqueline> I've sculpted a little horse piece that I'd really like to
Jacqueline> have made into a silver pin.  It's only about 1" square,
Jacqueline> relatively flat with a flat back.  I considered trying to
Jacqueline> cast it myself but I really don't know much about how to
Jacqueline> do it... I sent for the Rio Grande catalog and they have
Jacqueline> that rubber for making molds but it looks like it has to
Jacqueline> be vulcanized and I cant afford to pay $700 for one of
Jacqueline> their vulcanizing machines.  Am not sure what else could
Jacqueline> be used for making a mold?

If it is flat, then you can just use some mold release, and cast it
front side down in some Crystobolite (spelling?).  This looks like
Plaster of Paris, but is made for casting molds and takes heat.  Once
you have a block of Crystobolite with your shape in it, put it in an
oven and bake it to the highest temperature possible, going up slowly,
like 100 degrees per hour.  When it is completely hot, then you can
remove it and pour in the melted metal.  If your piece does not lend
itself to removal from a stiff mold, then you may want to go to RTV
silastic to make a negative mold, then more RTV for a positive mold
and then cast that in Crystobolite.

All the above is general knowledge from about 7 years ago when I was
doing lost wax casting.  You will need to research these techniques
for detail before proceeding, but at least it is a workable method to
research.

dion

-- 
Dion Hollenbeck (619)675-4000x2814     Email: [email-masked]
Staff Software Engineer     Megatek Corporation, San Diego, California

---

From: [email-masked]
Date: Tue, 8 Mar 1994 14:21:44 GMT

> Jacqueline> be used for making a mold?

I once used ceiling tile to make a simple shallow mold. Just cut two blocks
about 1" larger on all sides than you need. Make the cavity by cutting or by
pressing. Cut in sprues. Tape together and pour in your silver or bronze. The
resulting casting is usually rough and may have spikes coming out of it but its
very simple and inexpensive. The mold is not reuseable and is usually
destroyed by removal of casting.                               Bob

---

From: [email-masked] (David Hoopes)
Date: 8 Mar 94 13:06:09 GMT

>Any info is greatly appreciated.  Thanks!

I just signed up to take a bronze casting class.  The instructor gave me
the name of a local company where I could buy the wax.  It was close to
work so I went on my lunch break.

The company is 

CAST-TECH
523 N. Mur-Len
Olatha, Ks 66062
1-800-473-5944

They where very nice, and showed me around.  Along with casting wax, they
carry several differant types of flexible mold materials that can be used
for lost wax casting.  I got a good price on the wax.  I asssume since
they have an 800 number that they will mail order.  Give them a call

------------------------------------------------------------------------
David Hoopes                              Exabyte Corp.
[email-masked]                       11100 W 82nd St.          
Voice: (913) 492-6002 x3323               Lenexa, Ks  66214

---

From: [email-masked] (Jerry Cullingford)
Date: Fri, 11 Mar 1994 16:34:35 GMT

I'm not 100% certain, but I think you could probably use plaster of paris
for the mould. Apparently, cuttlefish (!) bone is also suitable if you're
carving a mould from scratch.
-- 
+------------------------------------------------------------------+     |
| Jerry Cullingford  #include <std.disclaimer> +44 442 230000 x3868|   ,-|--
| [email-masked] [email-masked]  [email-masked] |   \_|__
+-----(Work)--------------(Home)--------------(another alternate)--+ \___/

---

From: [email-masked] (Michael Covington)
Date: 13 Mar 1994 23:33:19 GMT

>carving a mould from scratch.

Just to fill in the story a little on cuttlefish:  The cuttlefish is an
invertebrate of some sort.  Its bone is a single elliptical piece about
10 cm long x 4 cm wide x 1 cm thick, solid, plaster-like in consistency
(easy to carve).  Cuttlefish bones are sold at pet shops because birds
and turtles like to gnaw on them (as a source of calcium).

-- 
< Michael A. Covington, Assc Rsch Scientist, Artificial Intelligence Programs >
< The University of Georgia, Athens, GA 30602-7415 USA    [email-masked] >
  <  Unless specifically indiciated, I am not speaking for the University.  >
For information about any U.Ga. graduate program, email [email-masked].