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In another thread, I mentioned using old scraps of non-Fe material to cast new bars, either of the same alloy or creating a mixture of alloys. I make a few different alloys in my shop this way. I have made Shibuichi, a form of red bronze, and some other stuff that just looks like pale bronze.

Preparation work:

 

If you are cheap like me, you probably have a can of small bits of various metals hanging around the shop. Here I have separated out a bunch of nickel-silver pieces.

 

1 scrap pile.JPG

 

If you will be mixing different alloys to try some new combination, you will need to buy a jeweler's scale and weigh the different materials. Jot these weights down so you have a "recipe" of sorts with the ratios by weight. This way, if you like what you made, you can get back to it later.

Now you will need some stainless steel HT foil. This is very handy stuff, and if you plan on making any stainless knives and doing the HT yourself. You will need to buy some. I bought a roll about 12 years ago and I still have a lot of it left. Cut out a piece of foil that will fold up into the size bar you wish to make. If you want to cast a bar 1" square and 4 inches long, cut a piece about 3" by 6 inches minimum. Fold it into an open box shape and fold the corners over. This one is 2"x4" and I should have made it narrower.

 

2 foil pan.JPG

 

Take some scraps of steel and start welding the steel crucible around the foil box.

 

3 Making crucible.JPG

 

Get the corners tight against the side of the foil box and weld a tail onto it. You will pull the crucible out of the forge by this tail.

 

4 Pan in Crucible.JPG

 

Use a propane torch to heat up the foil until it just starts to turn color. This oxidizes the surface. Load the crucible with your metal scraps.

 

5 Loaded crucible.JPG

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Heating

Pop the crucible into the forge. You want to be able to get upwards of 1850 for nickel-silver.

 

6 in the forge.JPG

 

When the metal collapses and looks like it has melted, turn off the forge and carefully remove the crucible to a flat stable surface to cool. Use a graphite rod to push the surface down into the molten metal below.

 

7 Molten.JPG

 

When you cannot push the graphite rod into the bar, it has solidified enough to remove it from the crucible. Grab the crucible with some tongs and bang it upside down on the anvil surface. It should pop right out. Quickly take it and press it or hammer lightly to consolidate. Then quench in a slack tub of water.

 

8 After quench.JPG

 

The foil will peel off easily. Anything that argues with you about that will disappear in 2 seconds with an angle grinder.

 

9 Peel the foil.JPG

 

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Using this stock.

 

Now I generally cut pieces off these bars and melt them in a standard clay crucible with an oxy-acetylene torch.

 

1-melt.jpg

 

I have some plate molds that make very nice 1/8" (a little fat for surfacing) plates. You melt the metal and pour it into the mold. In tis picture, I have shimmed the mold out an additional 1/16" to get a plate that is roughly 3/16" thick.

 

2-pour.jpg

 

The mold is opened and the plate is removed.

 

3-remove.jpg

 

These pics were from a set of Shibuichi spacers on a Bowie.

They now look like this

 

6 Finished.jpg

 

The same process was used to create red bronze guard and spacer for this little hunter.

 

Fittings V2.jpg

 

Have fun!

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Thanks for putting this together Joshua!  It looks like your corners are not welded shut on your crucible, and the foil is just folded over.  Is this accurate?  I would have thought that the molten metal would leak all over the place.  Do you find this to definitely not be an issue?  This seems so much easier than I would have thought if that is the case.  

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Jerrod, the foil is just folded over at the corners and the steel box is literally tack welded together. I have never had any leaks.

I have spilled some stuff out into the forge though.....:unsure:

Edited by Joshua States
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9 minutes ago, Bruno said:

Awesome info  Joshua! Thank you.  Now I have yet another thing to try...

Wait till you get into sand casting.......

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Hmm, It is a struggle to find nickel silver in the cross sections I want.  I never considered pouring my own plates.  You may have just set me free :)

 

Any thoughts on melting brass?  I have a lot of it about, but have been scared off casting it because of the zinc burning off.  However, I don't know if zinc burns off in an alloy, or if that is internet lore. 

 

Zinc fumes are seriously dangerous, I know that part isn't lore!

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6 hours ago, Brian Dougherty said:

Zinc fumes are seriously dangerous, I know that part isn't lore!

This is very true. All of these NF metals have zinc in them and good ventilation is critical.

Brass is difficult only because there are so many different grades and they all behave differently in the melt. I have mixed it into my red bronze recipe.

 

Those thick plates can be tricky. I have poured some stuff in 3/8” thicknesses, but I usually run into some air bubbles hidden in the casting. 

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You might want to try adding some flux to your melt.  It will help to gather up oxides and crap.

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Very cool. You make it look so easy. Been saving up all my nickel silver and brass scraps for this exact reason.

 

Was wondering if it is possible to pour into your plate mold from the initial melt, or is that just asking to make a hot mess?

 

5 hours ago, Gazz said:

You might want to try adding some flux to your melt.  It will help to gather up oxides and crap.

What flux would you recommend?

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Regular borax would work.

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I love remelting scraps, did it a lot in goldsmith training. That stainless steel foil trick is really nice.

 

I really like the red bronze you made, commercial bronze is often too yellow for my taste.

Would you mind sharing the recipe for that Yoshua?

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On 2/17/2021 at 6:20 PM, Bill Schmalhofer said:

Was wondering if it is possible to pour into your plate mold from the initial melt, or is that just asking to make a hot mess?

Probably get a hot mess. I use this mostly to mix alloys into a new compound with variations in color. So, it's best to form a large homogenous bar that I can cut pieces off of and pour small castings that will match when I need them.

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I have bought stuff from these folks so they send me emails regularly.  This video came in the email today and is about making an ingot from silver scrap but will apply to other non ferrous stuff;

 

 

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Good video Gazz. Thanks for adding that.

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  • 3 weeks later...

Thanks Joshua! Do you ever use a flux of any kind? The one time I tried making bronze in my small freon tank forge I lost a huge amount of copper to oxidation. Ended up with a bronze that had 20% or more tin. Probably says more about my forge atmosphere than anything else. The alloy, while not what I wanted was interesting and I discovered it is similar to alloys the Japanese make. It was a pale silvery gold color. Need to forge it down one of these days and make a guard or spacer from it. (I think I know where it is, lol)

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Honestly I cannot remember if I ever did or not. I have my ribbon burner forge atmosphere dialed in pretty tight, so I never noticed a problem with it. I have also heard of sprinkling charcoal over the top to help remove oxygen.

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