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I Forge Iron

So I want to smelt some brass...


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I've been buying up scrap brass from Goodwill and garage sales over the last few months and was planning on selling to the scrap yards. I've always been into lost arts and wanted to try to get into casting things and doing some metal art. I've watched a few hours of videos on youtube and have a pretty good idea on what's going on but I was hoping for some advice on making one from scratch and curious as to how much I should expect to spend on actually running it to melt the brass. I have about 60 pounds right now but they are mostly very small pieces like candle sticks and lamps I've stripped. All I'm looking to do is melt them down, refine them (just clean the slag well and have clean metal to work with, nothing more for the time being) and make some ingots. I'm not interested in scrapping them anymoreand I would like to start out with just making ingots I can set on the shelf in my workshop until I'm ready for whatever I decide to do with the next step. Is 50 pounds to much for one go? Is it to little? Please give me some advice so I can learn something useful that doesn't involve computers or other things I can't do hands on with a finished product to be proud of ;)

 

Also want to ad that I'm looking to do a gas foundry so no waste oil or coal or coke.

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Smelting is taking ore and making metal from it.  You don't smelt brass as it's an alloy You smelt copper and smelt zinc (quite tricky) and melt the copper and add the zinc  to make brass.  You want to MELT brass.

50 pounds is a lot to handle, definitely need two people to do the lifting and pouring.  You will also need a large crucible and "fancy" equipment to do it safely.  I suggest you start with a 5-10# melt to get used to the methods and safety equipment.

It's rather funny; but molten metal is much more dangerous than hot steel even when the steel is hundreds of degrees hotter, yet still solid.  Brass also burns off it's zink content making a toxic smoke and requireing you to add fresh zinc into the melt close to pouring time. I strongly suggest you go visit backyardmetalcasting.com and hang with the folks who specialize in this.

If I knew where you were at I might be able to make a suggestion as to places you could go.  I got my original training in an out of hours casting class held by a local colleges Fine Arts department.

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Ditto everything mr powers said. Especially the zinc toxicity and visiting the backyardmetalcasting site/find someone experienced. They've got bits and pieces that will help ya a lot. I'd recommend starting with a coffee can furnace, or making the same design a little larger.

 

I also highly reccomend that you start with a smaller melt and something that melts easier, and at a lower temperature, a lot of people start with aluminum.When you get ready to move up to copper alloys, silicon bronze is relatively cheap, and makes a very nice casting.

 

Charcoal, especially lump charcoal with a blower is a lot more bang for your buck and less complicated than propane while you're beginning. hmmmm, what else. Green sand casting is a good way to start. Splurge on good crucibles. Don't muck about with homemade refractory ones. They'll only break your heart and burn your legs and feet. Steel/cast iron ones can fail too if not very closely monitored or if they oxidize enough.

 

Be extremely careful, read all safety precautions and heed them, and have fun!

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Welcome to the forums! Pretty good bunch of folks here, always very willing to help.

Save yourself a ton of grief and possible injury- Check the forums and attend a workshop or some other kind of get-together where there is a real, live pour happening. Watch and ask lots of questions. Then you can try on you lonesome, with all the little things understood.

You could easily injure or kill yourself by just not understanding what you are doing.

Check around and find out where/how to attend a live pour.

And then report back! I have been toying with pouring brass guards right on my knives. The reason I haven't done so is because I don't now how and what to watch out for :)

Dave

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Also, I'll bite. there's not really any military posts up in that part of Va, are there? Are you Guard?

I'm Guard now, but was full time originally. I'm 80% disabled from the military and was discharged but I was able to join again in the Guard without pay so I did that :) I know it sounds dumb, but I like(ed) it. I get out this year though and am glad to be ;)

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  • 8 months later...

Copper is an element and zinc is an element. Brass can be an alloy of the two in differing percentage combinations. Therefore, you get different melting temperatures and different forging temperatures. Some can be forged at a low red heat. Some crumble when struck at a low red heat. Some get annealed by quenching at a low red heat; then cold forged.

 

Melting a bunch of found-object brass will yield and unknown misch masch. It'll be a crap shoot and a matter of experimentation.

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On 7/1/2014 at 2:31 AM, rjward1775 said:

Brass contains zinc, which burns out of the solution at melt temp.
Its also a powerful neurotoxin, so leave brass alone.

Where do you get this guff? It's as inaccurate as anything in RPG land.

Zinc is NOT a neurotoxin in any description or form. It takes either a personal sensitivity/allergy or a serious overdose to have bad effects. Zinc is a necessary mineral, without it we'd die and not too slowly. Overdosing on copper takes longer to get over if it doesn't do permanent damage.

Zinc does NOT "burn out of solution at melt temp." That's laughable on the face of it. Can you explain cast brass if that statement is true?

Believing the ignition temp for zinc being below? the melting temp for copper means they can't alloy just shows how little you know about metallurgy in general. Look up "eutectics" before you stick your foot in deeper. Forget the blogs, those are opinion and do NOT constitute research. For the most part they're more like reading the funny pages.

Sure there are exceptions, some blogs are a bunch of folk at the top of the curve swapping ideas, tips, tricks and problem solving but they're rare. You FAR more likely to run into folk talking about vegetarian geese, how vaccines are causing diseases, how "natural" means GOOD, etc. BLATHER.

Okay, that's maybe more harsh than it needs to be but pumping out dangerously wrong blather can endanger folk who likewise have too little knowledge to know it's blather. How about actually knowing what you're talking about before getting on the keyboard?

Frosty The Lucky.

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Frosty I'm afraid I have to disagree:

At pouring temperature the zinc is burning out of the melt with a bright flare.  You need to juice up the zinc content right before pour to get the alloy to not be zinc poor.  For small melts we use recent American pennies being a metered amount of zinc in a very thin copper shell.

There are many processes that work even though common sense says they shouldn't---you can dissolve copper in molten Aluminum when the melting point of copper is way higher!  Or may I mention "baked Alaska".

Historically metallic zinc was one of the later metals to have as a metal. The big issue was that the burning temperature of zinc was lower than it's smelting temp making the process pretty much a no go. Biringuccio mentions "colouring copper" gold colour by mixing zinc *ore* in molten copper. (De la Pirotechnia)  In India they figured a way to do it by smelting the ore in alembics that funneled the metallic zinc vapour into a cooler chamber kept full of a reducing atmosphere so the metallic vapour would cool and condense into a fine dust which then could be melted using regular techniques.

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I kind of relegate that type of "India" brass to the "mystery brass" pile, ya just don't know what's in it. I'd say it's pretty high in zinc, it tends to flare off at a bit lower temp than say plumbing brass. A cover for the melt is pretty essential for this stuff, and a furnace that's running a touch on the rich side to use up the available oxygen so the zinc can't react with it as easily. Charcoal makes a good cover, much less messy than borax and glass. It lasts a surprisingly long time in the crucible and is easy to skim off. Melt and pour in a WELL ventilated area. Like outside.

I do recommend starting out with aluminum first to get your feet wet (NOT LITERALLY!!!) with casting. Get a commercial crucible. Homemade equivalents just aren't terribly safe at bronze/brass temps. The pour temp is real close to the failure temp for the average welded steel crucible, and no, stainless will be no help at that temp.

You might just want to cash it in at the scrapyard as is, where you've already broken it down they may give you a better price for removing any chunks of iron.

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On 7/2/2014 at 6:03 PM, ThomasPowers said:

Frosty I'm afraid I have to disagree:

At pouring temperature the zinc is burning out of the melt with a bright flare.  You need to juice up the zinc content right before pour to get the alloy to not be zinc poor.  For small melts we use recent American pennies being a metered amount of zinc in a very thin copper shell.

There are many processes that work even though common sense says they shouldn't---you can dissolve copper in molten Aluminum when the melting point of copper is way higher!  Or may I mention "baked Alaska".

Historically metallic zinc was one of the later metals to have as a metal. The big issue was that the burning temperature of zinc was lower than it's smelting temp making the process pretty much a no go. Biringuccio mentions "colouring copper" gold colour by mixing zinc *ore* in molten copper. (De la Pirotechnia)  In India they figured a way to do it by smelting the ore in alembics that funneled the metallic zinc vapour into a cooler chamber kept full of a reducing atmosphere so the metallic vapour would cool and condense into a fine dust which then could be melted using regular techniques.

 

No need to be afraid to disagree, I'm in favor of folk pointing out where I'm wrong. You have me wondering how hot you're pouring brass, I used to catch grief from guys in metal shop class for wasting oxy acet melting brass into open face molds. I used to sell token to pocket watch size button thingies. Getting the bright blue green flare said I'd gotten it too hot, even so it made a nice bronzeish colored button thingy. Probably a way different thing eh?

I defer to your knowledge, you're much better informed metallurgically than I.

Frosty The Lucky.

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It's nice to have a discussion about Brass and it's pros and cons. Good cover reduces flare ups, quick pouring into the closed mold will keep white flames to a minimum and great ventilation is always needed for any type of casting. I would be more concerned with leaded brass and unknown alloys.

 

One thing to consider is, the person that started this thread has not been back on here since his last post. Oct 2013.

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But threads are not just for a specific person---we're throwing knowledge/experience out into the wind.

 

I can see where my casting methods: open crucible heated in a forge---usually coal; could lead to more flaring than other methods.  I generally cast into petrobond molds and was making mainly knife fittings

 

I much prefer casting silver (fine/sterling), copper or bronze (90:10) to casting brass though one of the reasons precious metals are precious is that they are easy to work with---save for the "modern" precious metals like platinum which was considered worthless in some earlier times and places due to the difficulty of working it, (though in South America they came up with a nifty depletion gilding method using ground up platinum in copper IIRC)

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  • 2 weeks later...
  • 6 years later...
  • 1 month later...

I have had plenty of luck with pouring brass from scrap, thrift shop stuff, etc. 

I had one accident, but that was me, not the material. However, I do believe I had it too hot when I poured that time. 
 

Here’s one example of a green sand molded punisher logo, it weighs about 1lb. Lol! 
 

0A6812CE-6825-4E58-82D3-25F8D4974CE0.thumb.jpeg.57b8d746128765e480dd68a1d855eded.jpeg

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  I like your punisher!  Here's a couple of skulls I produced back in my casting days.  I read your other comment about what can go awry, thanks from me as well for posting it.  I melted for years and am blessed that I never had one incident.  

IMG_0575_compress14.jpg

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