Pewter Casting in soapstone molds.

There is a lot of information on the internet about pewter casting. Here is one of the better sites. With information from this site along with trial and error, we set out to conquer the element of metal.
First of all, while reading about something is helpful, talking to someone who actually knows what the heck is going on is even better. Our own Baroness Valentina was instramental in pointing us in the right direction. Working on a shoestring budget, and armed with the knowlege above, we got started.

Step one: Soapstone

Soapstone is fairly easy to get and is one of the best mediums for casting. It is soft and can be carved in with almost anything. Our first piece was donated to us. All that needed to happen was to cut it into 2 pieces at least 3/4" thick. A band saw is the best way to do this. If you can not get to a band saw, a hand saw will work. The idea is to get two pieces that are cut straight enough so that when put together one becomes the mold and the other a backing plate. The pieces are now ready to be sanded smooth. You can tape a piece of fine sandpaper to a table and sand the piece until the saw marks disappear. You will want to rotate the piece every so often to ensure a uniform surface.

HINT# A piece of self adhesive sandpaper works really well when doing this. We used 320 grit.

Step Two: Carving

As I said before, Soapstone can be carved with almost anything. We used a combination of picks, chisels and a dremel.

HINT# You will want to have an exhaust fan running and wear a dusk mask because the WILL BE A LOT OF DUST!!!!!

The carving process was very easy. We made a cardboard cutout of our design and transfered it onto the soapstone with a permanent marker.
This is what our mold looked like when we were done.

One other important thing when carving is the sprue. The Sprue is the channel or funnel that the molten metal will travel down into the mold. You will want it to be 3/8 x 3/4 inches at its top, and taper to about 1/8 x 3/16 where it reaches the pattern. The position of the sprue should match its second half on the backing plate.

Step Three: Casting

Here is the fun part. Or at least the funny part. In the effort to save money, I went to an event and bought a pewter candlestick to melt down. Petwer melts at about 750º F. Easily obtained on a propane stove. At the local antique store we picked up two cast iron ladles to melt the pewter in. We cut up the candlestick and fired up the stove. When pewter melts it becomes like mercury. It looks silver with a blackish skin on it. After 30 min the candlestick was still there staring back at us. We finally decided that there was too much heat escaping from around the ladle. Not one to be defeated by a puny piece of metal, I made a burner that uses a propane torch. Enter the Burninator 3000

You may notice that the bottle attached is Mapp gas and not Propane. We tried the propane but couldn't get the "pewter" hot enough. "Better Living Through More Power" I always say, so we switched to Mapp gas. The candlestick was not impressed. Defeated and disgusted we called it a night.
After that embarassing insult we came to the conclusion that this candlestick was either made of some alien substance found at Roswell or we made pitiful Vikings. We chose the former and paid the money for some real pewter.

HINT# Just because it looks like pewter, doesn't mean it is pewter. In a pinch you can also use lead free solder found in your local hardware store. Solder is usually 92-95% tin and the rest copper or antimony.

Ok on with the casting. It is a good idea to clamp your mold together instead of holding it while pouring.

When you get the pewter melted, (It should take less than a minute or two) you will want to pour fast and evenly into the sprue filling it completely. Wait for the metal to frost over before pulling the mold apart. You may have to cast a few times before getting a good casting. The soapstone will absorb the heat from the metal and some of the more complex carvings will cast better in warm molds. If you notice that some parts of the mold aren't filling with metal. you may want to carve air holes int the mold. This allows air to escape while the metal is being poured.

HINT# Any water that comes into contact with the molten metal will result in a steam explosion that can 'shotgun' molten metal out of either ladle or mold. This effect is extremely dangerous, especially to eyes and any exposed skin. All molds must be ABSOLUTELY bone dry before molten metal is poured. A face shield is required when working with motlen metal. The wearing of gloves and a leather apron is also is required during casting.

Step Four: Finishing

Once you have a good casting, you will want to clip off the sprue and file the edges to get rid of any burrs. Pewter can be polished with most metal polishes.

HINT# Make sure your casting is cool before doing this.

Here are some of our castings:

 

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