Sunday, June 24, 2012

How To: Sand casting a sterling silver ingot

I needed to cast an ingot to make some half round stock for a knife with a reticulated silver handle I recently made. I used a simple cope and drag system and Pro-Craft fine grained premixed casting sand (reusable).

#1. For the form I used a round pencil.

#2. Packed the sand in one side, then put the other side on and packed the sand in.

#3. Pulled the pencil out and stood it up with a Jorgensen clamp.

#4. Melted the silver with a BernzOmatic Mapp gas torch, then grabbed the melting dish with some tongs and poured it in.

#5. Once it cooled, I took it apart and removed the ingot.

#6. After that, I just cut the top off, did some rolling and forging to make the half round stock.

I used the half round stock for the bands that separate the reticulated silver pieces on the handle.

8 comments:

  1. Thats awesome.where is a good source to find some silver spoons like that and what do you look for?
    cant wait to try some casting.
    Can I do that with copper too?

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  2. Jeff, I get the spoons at Tucson Stamp and Coin on Oracle, but you can check with any place that buys and sells silver and gold. Just check and make sure they are stamped "sterling". Yes, you can cast copper the same way.

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  3. You can reuse the sand, but each time you cast something you just need to scrape out and discard the charred part around the ingot. It doesn’t usually amount to more than a tablespoon though.

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  4. Do you need to use some kind of flux in the crucible?

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  5. Yes, I usually use borax, or a silver brazing flux paste.

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  6. I have the pro-craft flask as well, haven't used it yet as I'm concerned that the molten silver will freeze the second it contacts the gate of the flask because it's much colder than the molten silver. Have you ever had problems with this? I guess there's really only one way for me to find out and that's to try it, right?

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    Replies
    1. No, I never have had a problem with that. It mostly just contacts the sand until it's filled up.

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