Steel tools on copper alloys

Hi all, I have questions concerning use of steel tools when working with copper alloys.

I am using old bullet shells that I can get in bulk for my brass, the problem is they melt down from a full crucible to a little puddle in the bottom, so to "supercharge" my crucible, I have made what I am calling a charging ring. I cut a short length of steel pipe that fits nicely against the rim of the crucible, extending its height and allowing me to stack more shells on top that then melt down and form a half full crucible. I then lift off the charging ring and top up the crucible. A whole lot faster, saving time and gas... and also preventing a recurrence of the "incident" I had that made me glad I wore all the cumbersome and humid safety gear.

I use a length of stainless steel flat to pick up the slag from the top and give the molten pool a bit of a mix.

I also would like to make some brass and copper rod, I plan to do this with a method I saw where a home foundryman poured aluminium into seamless stainless steel pipe standing vertically, upon cooling the aluminium contracted enough that the aluminium rod dropped straight out when the pipe was lifted off.

So my questions are, how detrimental is it to bring steel into contact with the molten brass? In the case of the charging ring there is little contact with molten brass as it fall away into the crucible, but my slag scoop gets dipped right in there.

Will the rod making method work with brass and copper? Or will it get stuck and need machining off? Could I use carbon steel pipe to cast into or will this cause more problems?

Any other simple methods to produce rod?

 

Well, let's see. I do know that iron will leach out of ferrous metals into molten aluminum, and molten copper/brass. Worse in copper alloys, and that's why steel pipe crucibles have a short life when melting copper alloys.
That being said, I doubt you'd contaminate your coppers to any great extent by just using a bit of stainless as a stirring/slag scoop.

Now, the cast rod idea has merit, but coppers shrink less than aluminum, so it may just hang up in your mold. You might be able to get away with it if you polish the roughness out of the inside of your molding pipe. That would take away anything for your molten copper to cling to, and help the cooled product slip out.

Just my 2-pence.....Roger

 

I agree with Roger, I doubt minor contact with a slagging tool is enough to create problems. I’m pretty confident that if you fill a pipe with copper alloy you will end up having to machine it off. I made some angle iron ingot molds last year and they worked fine for aluminum but when I poured silicon bronze in them they stuck - almost hopelessly. Extracting the ingots was an adventure story for another time, but suffice it to say it was unpleasant. So no, I doubt they’ll come out of the pipe.
Lost foam might be a viable method. You might be able to find suitable foam rods at a hobby shop or art supply.

Pete

 

yes purchase it

if your shells are not CLEANED your resulting brass will be contaminated with Sulfer which makes the brass Brittle VERY BRITTLE, like glass , it will polish up awesome, but if you drop it , you will have shards, you are much better off to sell the shell casings , and buy real brass rod ,
if you are working with rimfires, there is no method I know of for getting them clean , that is why good scrap yards wont even buy them, they are considered a containment, and may get entire container loads of scrap rejected

everything you have been told about steel above is 100% true , limited contact with tools is fine, but steel crucibles are Bad, very bad

V/r HT1

 

Right, I will keep using the tools as I am, which is good because the charging ring sure saves time, and gas.

I am currently using green sand molds with a piece of pipe as my pattern to make rods, like what is described above by Al203. It works, but I would like to speed up the process and pouring into pipe seems like it would be faster and simpler....provided it works. I guess I will have to give it a go with a short length and find out. Maybe I could press the rod out if it got stuck, maybe a dash out graphite on the inside will help. I'll let you know how it works out.

Buying it sure would be simple, but 5 times the price. I have bought plenty of rod in the past for this project and am looking to cut costs for future units. A 5x reduction in material costs is very attractive, as well as the fact that I can produce rod to whatever length I desire and don't have to purchase a minimum 3.6m length.

I tested a couple of pieces for brittleness, stuck them in the vice and beat them with an ugly stick. They bent over like brass does and did not break or shatter. Maybe I got lucky with that batch? I assume the sulfur comes from propellant residue, in which case, for future batches, I will run the shells through my case tumbler, this will clean them up nicely inside and out and leave me with clean and shiny brass.​