Blue streaking in lead smelting ingots

[bigborefan]

Just got through smelting some scrap lead into ingots and run across this situation. I melted some straight pure lead from blocks with no problems. When I smelted some sheet lead, I kept getting a bluish color appear on the surface of the liquid lead. After fluxing numerous times, the blueish what looks like oxydation reappears immediately after cleaning the surface. When I pour into ingots, the blue shows up prominently on each ingots facing as seen in the picture below. I read previous threads on people having a similar problem and in each case it was suggested that the temperature of the metal was too hot. I use a Lyman lead thermometer that shows the temperature doesn't go above 700 degrees. Do they mix anything with sheet lead to explain this problem? The ingots test out to pure lead BHN so except for coloration, they should work out with a little tin for BPCT shooting. Anyone have any idea what causes this?

[milkman]

I asked the same question awhile back. The blue or gold color is an indication of pure lead, is the answer that I got.

milkman

[bigborefan]

Milkman,It could very well be. I've been casting bullets for over 25 years but this is the first time I have ever worked with pure lead. All my casting in the past was with WWs and linotype.

[Bigjohn]

I have always had that colour streaking when casting prue lead. It is basically an indication of prue lead hence nothing to worry about.

The only addition to lead sheeting which I know of but not what effects it may have on casting is a process called 'Copperised'. This is supposed to add a matrix of copper to the metal which prevents gravity causing the lead sheeting to 'flow' (move) downhill (roof slope). This should skim out in 'smendering' (a.k.a. Smelting to render metal in to ingot form).

Nice ingot, would you like to send me some? Trial purposes only.:kidding:

BTW Bigbore It appears you have one of the Reversed "N" Lyman ingot moulds there. I'd hide that from the rest of the members here as they may beat a path to your door in ore.

John

[bigborefan]

John, I've had that ingot mold for years and never even noticed the backward N. Even after posting the picture, I didn't notice it.

[leftiye]

Those cast ingots that sell for $63 an lb.! You're definitely in trouble!

[floodgate]

I checked my Lyman ingot mould again, and it STILL has the "N" right-way-to; it is the "L" that is backwards; the other letters are OK.

Confused...

floodgate

[Dale53]

floodgate;
apparently, Perception is everything[smilie=1: [smilie=1:

Dale53

[cohutt]

You got me wondering about my last pure smelt-down. I dug out a couple fo pics of the night's work and found the blue hue is noticeable even in a "group photo". I am very confident this scrap was as pure as pure gets due to the source's specs for their raw materials. In sunlight the color has a little more purple in it, some rainbow looking edges too. In the photos it all looks blue.
My bet is that yuur ingots are fine- the blue is the confirmation. BTW 50/50 pure and ww is turning out to be a very satisfactory alloy @ 800-900 fps 44mag & 45acp loads. Right now i have better sources for pure than ww's so i am trying to stretch any alloy out as much as i can.
edit: This pure lead was also remannts from lead sheet.

http://i107.photobucket.com/albums/m284/cohutt/leadingots002.jpg

http://i107.photobucket.com/albums/m284/cohutt/leadingots001.jpg

[Bigjohn]

cohutt,
That's a mighty fine collection of ingots you have there and the blue colour as well. Looks like you have been very busy.

The blue remains even as the ingots tarnish IME.

John.

[cohutt]

cohutt,
That's a mighty fine collection of ingots you have there and the blue colour as well. Looks like you have been very busy.

The blue remains even as the ingots tarnish IME.

John.


:-D Yeah I hit a couple of loads of pure lead scrap that was very clean, have done 3 runs like that one while weather wasn't too hot. Total so far about 600 lbs, another 150-200 to go. My problem is that i haven't gotten completely off my *ss about hooking up a reliable source of ww or alloys, just scavenging and trading here and there for it.

[Andy_P]

I melted a bunch of what I believe to be pure lead, and one batch has the bluish tinge and the other doesn't.

So am I to believe that if it aint bluish it aint pure lead?

[Sundogg1911]

in my pb ingots, sometimes I see that and sometimes I don't. Mine actually seem to have more of a Purpleish tint to them. don't notice it in my Lino or WW ingots though.

[bigborefan]

Of the two batches of lead that I smelted that day, one being the sheeting and the other being blocks of lead. They both tested out to a 5 BHN or pure lead, but only the sheeting lead showed any off colors. The lead blocks came out shiney silver looking with no other coloration at all.

[piwo]

I'm using plumbers lead and my ingots are also turning out with bluish coloration so the "blue thing" with pure lead strikes again. I have a question about the golden color as well. First the backdrop……….

Before coming here to this forum, I was casting for roundball only, and poorly: wrinkles and really ugly results. The recommended solution here was: TURN UP THE HEAT"... I am now casting for BP conicals as well as RB, and my results are getting better and better. My only ladle casting session was not great, and I went back to the comfort zone with the bottom pour yesterday. It was my best casting session yet, and I couldn't help but smile each time I dropped the .54 boolit out. This means I smiled 96 times in a short period of time yesterday (a couple frowns and confused "what happened" as well) and that is never a waste of time.8-)

I found my rhythm was best when the pure lead was VERY hot. I knew it was right when the golden “film” appeared on top of the mix. How hot I don't know since my casting thermometer was imbedded in a smelting pot I had to shut down quickly one evening and forgot to remove it, but that’s a different story altogether.:oops:
I just know the lead is just right when golden patina coats the top of the lead. The lead pours out predictably at any rate I wish. If I want to slow pour at this temperature, no problem. If I want to open full throttle, it pours true. I did best with a moderate or slower pour into the hot steel mould and the boolits looked more like the results I see others getting here: complete fill-out, sharp edges on the grooves, no wrinkles.

So, what is the golden film that coats the top of the pot? Good, bad?? And can you heat your pure lead too hot? I’m sure SOME temperature is beyond the “castable”, or safe level. Just curious what that is, OR, if a little Lee bottom pour is capable to achieving this temperature whatever it is.

[cohutt]

I'm using plumbers lead and my ingots are also turning out with bluish coloration so the "blue thing" with pure lead strikes again. I have a question about the golden color as well. First the backdrop……….

Before coming here to this forum, I was casting for roundball only, and poorly: wrinkles and really ugly results. The recommended solution here was: TURN UP THE HEAT"... I am now casting for BP conicals as well as RB, and my results are getting better and better. My only ladle casting session was not great, and I went back to the comfort zone with the bottom pour yesterday. It was my best casting session yet, and I couldn't help but smile each time I dropped the .54 boolit out. This means I smiled 96 times in a short period of time yesterday (a couple frowns and confused "what happened" as well) and that is never a waste of time.8-)

I found my rhythm was best when the pure lead was VERY hot. I knew it was right when the golden “film” appeared on top of the mix. How hot I don't know since my casting thermometer was imbedded in a smelting pot I had to shut down quickly one evening and forgot to remove it, but that’s a different story altogether.:oops:
I just know the lead is just right when golden patina coats the top of the lead. The lead pours out predictably at any rate I wish. If I want to slow pour at this temperature, no problem. If I want to open full throttle, it pours true. I did best with a moderate or slower pour into the hot steel mould and the boolits looked more like the results I see others getting here: complete fill-out, sharp edges on the grooves, no wrinkles.

So, what is the golden film that coats the top of the pot? Good, bad?? And can you heat your pure lead too hot? I’m sure SOME temperature is beyond the “castable”, or safe level. Just curious what that is, OR, if a little Lee bottom pour is capable to achieving this temperature whatever it is.


Just oxidation I believe. When smealting pure lead i see a goldish colored film vs the more silver looking ww skim layer.

[piwo]

exactly! just wanted to make sure I wasn't pushing it too hot.... if there is such an animal.

Thanks!

[shooter575]

I cast a lot of dead soft Pb also.I get the blue most of the time,sometimes gold,sometimes both,and then seldom I get no color at all. I also cast HOT ie 800-850 F The only danger area would be vaporization temp up around 1300F.None of my electric pots will get to 900 so I dont worry about it
Now too hot can can screw up some al moulds.But I have had no problem at the 850 max I use.

[USARO4]

When I melt pure lead I get gold tint and blue tint, sometimes both colors combined all out of the same lead batch. When it's combined it looks like case harden finish on a gun. I think it is a result of the temperature of the melt. More heat = pretty colors.

[STP]

I work wholesale plumbing supply and the plumbers lead ingots show the blue color. Rarely called for these days.

[MakeMineA10mm]

This reminds me of when I was in High School and my best shooting buddy decided he had learned all he could about guns, and was starting to use a bow and arrow for everything.

We were "patrolling" around his yard (he lived on a farm in the country), he carrying his bow, and me my 44 Magnum. He spotted a crow perched at the very top of a very large spruce tree in his side yard. He shot all three of his "foo-foo" arrows at it (arrows designed to hit birds at relatively close range), and missed on all three shots. He then sent two field arrows at it, and also missed. At this point he was getting angry, cause the crow was actually sitting there cawing at us, almost like laughing... I wouldn't shoot up in the air with my 44 Mag, so my buddy asked me to run in the house and grab his shotgun and shoot that S.O.B.!!!

I did so, but I couldn't find any ammo in the usual places we kept it. I finally found a box of 12ga behind his bedroom door. I shoved three or four shells in the gun and ran outside. My buddy was even more tense by now with the crow still mocking him, so he was screaming, "shoot him! Before he flys off..." So, I took a careful bead, and cut loose.

I heard the most unusual sound I ever heard when firing a gun. It sounded like a cross between shrieking and whistling. My buddy and I looked at each other with a "what the he!l was that?" look, especially since the crow was still there... (Back in those days my buddy and I shot every day at least 100 rounds, and we rotating among rifle, shotgun, and handgun. We were really good and virtually never missed, if I do say so myself... Can't claim I'm still that good unfortunately...)

Anyway, I shot again, and then my buddy asked where those shells came from. I told him behind his bedroom door and he groaned, "those are BUCKSHOT!"



The reason I'm giving you this seemingly unrelated story?

Well, the old timers used to call buckshot "BLUE WHISTLERS," because the pure lead they were made of had a blue tint, and they tended to whistle as they flew through the air...

So, as all these guys have reassured you, blue means pure lead, and there's nothing wrong with your lead or ingots.

By the way, after having five arrows and two loads of buckshot fired at him, the crow finally took off, totally unscathed... We had some really good fun that night and the next regaling our friends with the story and laughing to ourselves about what the crow must have been thinking...

[Beaverhunter2]

Wow! Am I glad I found this thread. I just smelted a 53lb block of mystery metal that my father-in-law gave me, I was hoping it was pure lead (or pure enough for Blackpowder) 'cause I was down to 7 lbs of pure. Halfway through I started gettin purple and blue ingots and green, gold, and purple dross. It seemed soft but I was getting worried. Now I know I'm back in business!

Thanks for all the great info, guys!

John