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Anyone mixed copper and brass?


Savage

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Hey guys howsit going, well ive got a few old welding bits in the shed that are beyond reusing and at the same time I need some pommel, guard and bolster material but don't really wanna use straight brass or copper so I thought of smelting the two together and giving it a few stirs to see if ill get a new color or not.

Does anyone know what color ill get by mixing the two?

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you may adjust the shade a bit, but i cant quantify by how much.  you can try looking up the alloy contents of your brass and then see what the final content of the mix would be and check if that is close to a different existing alloy and what that looks like.
 

one of the items on my ever growing test list has been to cast an ingot from two different metals poured simultaneously into the same mold to see if i can generate turbulence patterns with swirls and the like.  that would probably give your furniture a lot more drama (provided of course that it works...)

 

post pic's of whatever you end up doing though, sounds like a fun exercise in metallurgy :)

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that does sound exciting, not that it will work the same as paint but I found out that a yellow and a pink color paint makes a sort of red color, if I can achieve a red from the two that would be very interesting as a guard or pommel id say. maybe if I add more copper than brass or visa versu. I don't have a crucible yet but will look for a cheap one as I will probably only do this once unless one of you know how I can make one for one time use only, I have a workshop at my disposal. I have smelted brass and also copper before but im no pro like most of you guys but should I put any flux in the crucible at all? I didn't use any in the past but that was more for the fun of melting stuff never to actually have the need in using it haha.

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alloy colors do not necessarily behave like pigments, so don't expect the same results, after all brass is gold/yellow generated from copper (kind of a salmon-y pink) and zinc (silver/grey) its not so clear cut as blue and yellow make green.

 

you can heat treat plain copper with a torch to pull some really vibrant red's, you will probably need to experiment with the timing to get it at the right temperature and expect to lose some of the potency if(when) you put a finish on it. if left unfinished the colors will fade and be vulnerable to wearing off or tarnishing.

 

take a read through the stickies at the top of the list and search for 'brass' and 'copper' and 'flux' when you are on the foundry and casting thread index to narrow the search results to this section only.  make sure you are using sufficient PPE and work in a well ventilated are if you are melting alloys containing zinc.

 

if you are as green as it sounds like you are I would HIGHLY recommend not trying to make your own crucible (and that's honestly not intended as a jab, just observing that this sounds like your first attempt at serious casting with a controlled outcome, not to mention attempting to alloy your own ingot) you can pick up small crucibles for around 8-10$US online, you can make your own handle for it or buy that as well.  shipping to NZ however.....

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yup its my 1st time at serious casting brass and copper but aluminium on the other hand ive done endless amounts of it from old cans and what not. For this 1st attempt at mixting the two I will only do a small amount to see if I can add certain

colors of the two in order to change the over all color, even if it doesn't change it much it should be fun. theres a ceramics shop near by and I might call them to see if they got a crucible.

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I think that if you want the swirly pattern without doing the mokume-gane thing you will need to have one of you metals near a temperature where you can stir it like mashed potatoes and have it stay in peaks and valleys while the other metal will need to at a very high temperature at pouring temperature so that it fuse and bind to the other. After this lump has cooled you may be able to draw it out by forging but it could be a bit difficult if the two metals a very dissimilar, they could crumble if forged to hot or if not annealed often enough if forged cold split.

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I figure it should forge as well or poorly as a mokume billet of the same materials, and in small quantities you should be able to just pour them into the mold simultaneously and the metals should freeze before they can start to homogenize into a new alloy.  that part of the process is going to be the lions share of the experimentation.

 

savage, see if you can track down the exact alloys of your starting materials and check online if your mixture already exists and has photos.  otherwise, I would make up several test batches with increasing ratio's of starting material and track what went into each for future reference.  you can stamp numbers or percentages/descriptions into the final billet afterwards for clarity.  if you just start with a lump of copper and toss in some brass, check the result, remelt and add more brass rinse and repeat you lose the opportunity to keep the samples, and photos are only so useful (cant test a patina on a 4x6 glossy or a jpeg).  plus extended and repeated trips to melting temperature can cause burnout (think zinc) which will introduce another variable into your alloy ratio.

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Sounds like a fun experiment, as for the tracking id have no idea where or how to start as these are all old tips and nozzles ive picked up over my time and not all of them are the same tips or nozzles. I will record my main variables like how many copper tips I used and how many brass nozzles I used and so on, I also have a copper piece around 3mmx60mmx5mm that i have but that ones intent is for Mokume when i have got a big enough forge and can bothered lol.

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if you can pull the manufacturer/make/model numbers or compare them to similar items you might be able to look up the specs for them.  you are referring to things like mig tips or torch rosebuds and the like?  i wouldnt hold my breath trying to recycle that kind of material, not all metals are intended for casting.  but so long as they are not alloyed with known hazardous materials give it a try :) (ventilation still a must regardless)

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Mig tips yes but no numbers. And dont know what a torch rose bud is but its the brass part that the mig tip scews into. When you say not intended for casting what do you mean? I just want something experimental to do and at the same time use the final product as a knife guard and pommel if its good enough.

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some alloys are formulated with a specific use in mind and have elements added that make them more suitable for that use.  

 

for instance 360 free machining brass has lead added to make it softer and easier to machine, but makes it less desirable to forge/form.

http://www.anchorbronze.com/c36000.htm

versus something like 260 cartridge brass which has an 'excellent' rating for cold work and is pretty close to nominally 70/30 copper/zinc, they dont even give it a machinability rating.

http://www.anchorbronze.com/c26000.htm

 

so melting something like 360 can expose you to lead, and then whoever handles the knife afterwards has been handling a lead product as well.

 

take a guess as to what brand of supplies you tend to buy and look those up so you can get a ballpark estimate of what you are working with.

 

http://www.google.com/search?client=safari&rls=en&q=torch%20rosebud&oe=UTF-8&um=1&ie=UTF-8&hl=en&tbm=isch&source=og&sa=N&tab=wi

rosebud's are gas torch tips

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Ok so im sure this stupid but ill probly do it anyways lol, im gonna make a small steel crucible(with a very long handle to stay far from the hot side) and cover the inside with fire clay mixed with abit of grog or silcon carbide just to keep the molten metal away from the scale forming from the steel crucible, as I said its a 1 time use only, if I decide I like the end result enough I will purchase a proper one,

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no offence but im not paying 100 bux for crucible I plan on using once, and I managed to pick up some pretty solid fire bricks from a kiln plan and the guy gave me a few cubes and said to use a big drill bit and make one from a cude, and also picked up a kiln shelf for 10 bux haha

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For small knife fittings I have used stainless steel creamers bought cheap at the thrift store or fleamarket.  I build a "Mount Fuji: fire lay lots of coke under it and then a cone with a center hole for the creamer.  You do NOT want to oxidize a hole through them!!!  (A particular heavy walled one gave me 4 melts before it got spooky thin!  Not bad for a quarter...

 

PLEASE NOTE "Smelting" is making metal from ore.  "Melting" is taking metals and melting them---foundry work.

 

So if you are taking bluegreen ore and making shiny copper from it you are smelting if you are taking scrap metal and melting and alloying it you are *melting* it.

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none taken savage, i dunno what the supply is like or shipping pans out to get something to NZ, but i can get 7.5oz crucibles for around 9$ pre-shipping here.  doesnt look like they ship beyond USA/PR/Canada though.  the fire brick cube sounds like it could be a good solution though.

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only thing i can say is that it will depend on the type of brick (soft vs hard).  you want to avoid having it crack when you drill to prevent it from falling apart at temperature.  never asked how much you are actually planning to melt either.  are you going to need to drill out a 1/2" cavity to contain a little metal, or a 2" cavity to contain a lot of metal?

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id put some strapping or tie wire around the brick to help prevent it from coming apart if it does end up cracking.  some kind of masonry bit is probably where you will end up, is there a hardware store with competent staff nearby that can provide some more reliable direction?  maybe you can pump the guy that gave you the bricks for something a little more descriptive than 'big' too :)

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