source for scrap copper

[Cat Whisperer]

Here's a fellow with a couple of buckets of it he can't sell.

http://castboolits.gunloads.com/showthread.php?t=86579

[dan610324]

sorry to say , but it aint pure copper
its an alloy called tombak and cant be used for cannons

[GGaskill]

American bullet jackets tend to be made from "gilding metal" which is 95% copper and 5% zinc.  You could make gun metal from it by adding tin but not artillery bronze which has no zinc.

[dan610324]

yes , 88-8-4 I think the proportions is
but check it up carefully before useing it to cannons that it doesnt contain any lead
the best cheap copper scrap is electrical wires , then you know its pure copper

[Victor3]

 Other than health reasons, is there a problem with a little lead that would make the copper no good for making bronze?

[dan610324]

it makes it weak , dont know how much but it of course depends on how many percent lead its in it .
I dont know how large the difference is , and I dont want to find it out either 
so because of that I think its better to only use pure metals when mixing bronze for cannons
if you make something else it doesnt matter as long as it isnt bells
bell bronze contain between 20 and 30% tin ,
that alloy will be very very hard , but also too fragile to use in cannons

[Victor3]

 I thought lead burned off after a short while at temps required to alloy copper with tin (?)

[dan610324]

no it doesnt , ok maybe a small amount does
but not much , maybe the oxides , dont know at all .
I guess that you need to reach the boiling temperature for lead until you can reduce it from the molten alloy by temperature only . boiling temp for lead is 1750 degrees celsius

[Cat Whisperer]

I'm often amazed (and pleased) at the amount of information that comes forth from just tossing out an idea and watching the discourse.

If only politicians could discuss issues in the same manner!

[dan610324]

as long as they only are interested to get a high salary for their own living it will never happened
but no such discussions here 

tossing ideas is good , the more stupid the better
all ideas are good ideas until the opposite is proven

[1Southpaw]

boy was that a stupid idea .

[Double D]

So what is the alloy of artillery bronze for making cannons?

[Cat Whisperer]

boy was that a stupid idea .

And which one of us hasn't done it?   

Let he who is without sin cast the first stone.

[Cannoneer]

A 90:10 copper-tin alloy is usually given in most sources (and for this reason quoted by many people) for the casting of historic bronze artillery. 

[Double D]

A 90:10 copper-tin alloy is usually given in most sources (and for this reason quoted by many people) for the casting of historic bronze artillery. 
[/quot

Thank John, I thought that was what it was.

[Cat Whisperer]

A 90:10 copper-tin alloy is usually given in most sources (and for this reason quoted by many people) for the casting of historic bronze artillery. 

Are there better bronzes?

[RocklockI]

boy was that a stupid idea .

Hey1 South Park  , tell us what you really think ? No more of your sugar coating !

[GGaskill]

Are there better bronzes?

I think so.  Compare the physicals for C90700 (90:10 Cu/Sn) with those of C65500 (Everdur) and AISI 1018 (mild steel).

For C65500, tensile is 92 Ksi, yield is 55 Ksi and elongation is 22% versus tensile of 42 Ksi, yield of 25 Ksi and elongation of 10% for C90700 versus tensile of 65 Ksi, yield of 45 Ksi and elongation of 20% for AISI 1018 (mild steel.)  I would say Everdur (C65500) is more than twice the alloy that C90700 is. 

What we have is a lot of experience with 90:10 bronze cannon and little experience with Everdur.

Gary--did you get the Everdur?

[RocklockI]

Yes my foundry poured guns are everdur . I will continue to use 90 /10 in the backyard.

[GGaskill]

Yes my foundry poured guns are everdur.

They seem to be coming out pretty good.

[dan610324]

there is a lot of stronger modern or semi modern bronzes
the best known is probably the 88-8-4 (gunmetal)

earlier the bronz mix was different between the foundries ,
and even between different masters at the same foundry

the differences could be hughe

[RocklockI]

Dan ,Maybe you should tell those igorants amost us what is .... 88 - 8 - 4 ?


er   ... I mean Dem ignorant ones ..not me , of course .....

  is it 88 copper 8 tin and 4 zinc (such an ugly metal)  (except of couse for the civil war zinc fuses they are cool because they where cutting edge then)thats my best unignorant guess .......

George they are coming out nice ...depending greatly on my wax work ......at least "thats the rumor" .

Gary who does not care for zinc .


ETA George That sig. line is one of my favorite all time saying ...... except ....... mostly .....I've a no heart kinda guy all my life ......BUT That is a fine saying  , another of W.C.'s saying is "If I am ever shot at , I hope it is with a machine gun at 100 yds "  I think he was speaking Mauser pistol machine and not a maxum .

I think he also said "there is no greater thrill than to be shot at and missed !"

My dad taught me to admire Chuchhill and despise DeGaule .....and so I do .  I could have teddy and churchhill combined here ....?

[dan610324]

correct , 88% copper , 8% tin , 4% zink
that one is stronger than the 90-10
but as Im more interested in the early cannons I think the 90-10 is the alloy for me

not to mention that the color of the 90-10 is in my opinion much more beautiful
or even an 92-8 mix

[GGaskill]

DeGaulle had an excuse; he was French.

[Victor3]

Are there better bronzes?

I think so.  Compare the physicals for C90700 (90:10 Cu/Sn) with those of C65500 (Everdur) and AISI 1018 (mild steel).

 1st thing I checked into before I laid $$$ down for a Morko was what the heck Everdur is. I was pleasantly surprised with its properties. Aside from good strength, it reportedly pours and fills moulds beautifully and results in castings with minimal porosity (very important for a barrel).

 If I ever get going on backyard bronze casting I don't think I'll mess with anything else for cannons/mortars. It seems like a safer way to go compared to some of the other popular castable alloys.

 I think Gary did good by choosing Everdur. His Morkos will never turn into 'bobble-head' handgonnes. He must be an artist and a metallurgist.

[gulfcoastblackpowder]

When Gary told me he could have mine cast in the Everdur or I could wait and have him cast it in 90/10, I also looked into the Everdur.  It seemed superior in every way.  I would have preferred to have it cast by Gary himself, but it's still fully a Gary production.  The pouring is probably the most insifgnificant part of the process - he did the design, the wax, and the finish work, so a few minutes of pouring doesn't really matter, and I knew he was really wanting to get some completed, which would have taken longer in his backyard setup.