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doulos
01-06-2022, 05:46 PM
I was given some lead. It was supposed to have been used as ballast weights for stage curtains etc. It is dead soft (about 4- 5bh with the pencil test). Thuds when you drop it and dents easily. It came in some big 40nlb chunks. It seemed like pure lead to me. So I decided to cast some .58 roundballs with it. Mind you almost all of my casting has been with hardball or 20-1 when I had a BPCR.

I cut off a chunk with a sawzall and threw it in a LEE mag melter. I fluxed with saw dust and skimmed a ton of dross that seemed bronze in color . I casted some roundballs and seemed like I had to flux every 10 balls or so. Dross seemed to stick to my ladle. So i kept fluxing. I tried candle wax and Marvellux. Same results.

I tried adjusting temp. Which is no easy feat to be consistent on my pot. When casting at between 700 and 850 the results were pretty much the same. The ladle looks like it had a copper colored rust on it. And would collect dross on it really fast if I didnt keep the temp hot. I could not keep the ladle clean. Even with the melt very hot.
I have only cast roundballs a couple times with pure lead and didnt have this issue. I never had this casting bullets with harder alloy.

I cast about 85 and quit. Even as hot as I was casting none were frosted. Some looked like I wasnt waiting long enough to open the mold becasue the sprue doesent look like a clean cut. But most of them seem ok.

I am not a experienced caster compared to many people on this site.
So my question is this. Does this stuff seem contaminated with something?

Rickf1985
01-06-2022, 06:54 PM
Sounds almost like tin to me. That would be a freakin' gold mine if it were. Tin is going for 29.00 a lb.!!! You may want to have a chunk of that analyzed.

Winger Ed.
01-06-2022, 06:57 PM
Send a sample to the guy here that will analize it for the sample.

kevin c
01-06-2022, 07:00 PM
I have pure lead analyzed out to 99.99% by XRF, and don’t recall seeing what you describe when I melted it down, so I’d guess you have something besides lead in there.

Pure lead does have a higher melting point than a lead alloy, though. Maybe the top of the melt is cooling too much? On cold days casting outside, I almost always have what looks like dross on top of a melt of clean alloy of known content that I think is just cooled alloy (I’m having some analyzed to be sure).

doulos
01-06-2022, 07:20 PM
I have pure lead analyzed out to 99.99% by XRF, and don’t recall seeing what you describe when I melted it down, so I’d guess you have something besides lead in there.

Pure lead does have a higher melting point than a lead alloy, though. Maybe the top of the melt is cooling too much? On cold days casting outside, I almost always have what looks like dross on top of a melt of clean alloy of known content that I think is just cooled alloy (I’m having some analyzed to be sure).
It was cold out side today. I was in my garage with both doors open. It was only about 25 today. I cast by the back door and a breeze is always coming in behind me blowing any fumes out the front. I have never casted when it was like this out side.

doulos
01-06-2022, 07:21 PM
Send a sample to the guy here that will analize it for the sample.


Who are you speaking of?

Winger Ed.
01-06-2022, 07:40 PM
Who are you speaking of?

I can't remember off the top of my head, but he's a regular poster and folks refer to him,
or see him all up & down here when the subject comes up-- which is often.

Wilderness
01-06-2022, 08:01 PM
Doulos - I presume you know what your roundball should weigh from previous experience with "good" metal, or even from what the mould is "supposed" to cast.

I suggest you weigh the balls you have just cast, and compare. Most of the stuff that might be a contaminant - tin, antimony etc is about 60% of the weight of lead, so will pull down the weight of the alloy accordingly. Non-lead content of 10% would reduce the weight of the ball by about 4% (0.9x1.0 + 0.1X.6 = 0.96). Mind you, this much tin or antimony would make a hard alloy, so think proportions rather than absolutes. You might pick up a couple of percent of non-lead.

This test also will at least confirm that your metal is not tin - which would make a ball weighing about 60% of what it is supposed to be.

Hope this helps.

doulos
01-06-2022, 08:24 PM
Doulos - I presume you know what your roundball should weigh from previous experience with "good" metal, or even from what the mould is "supposed" to cast.

I suggest you weigh the balls you have just cast, and compare. Most of the stuff that might be a contaminant - tin, antimony etc is about 60% of the weight of lead, so will pull down the weight of the alloy accordingly. Non-lead content of 10% would reduce the weight of the ball by about 4% (0.9x1.0 + 0.1X.6 = 0.96). Mind you, this much tin or antimony would make a hard alloy, so think proportions rather than absolutes. You might pick up a couple of percent of non-lead.

This test also will at least confirm that your metal is not tin - which would make a ball weighing about 60% of what it is supposed to be.

Hope this helps.
Thanks
Any cast .570 roundball Ive weighed has always been around 278 grains. I weighed about 20 they were all between 277.5 and 281.4. And there was only 2 under 279 out of the 20. So they averaged right around where they should have for the ones Ive weighed before. That includes commercially bought and my own cast.

Rickf1985
01-06-2022, 10:03 PM
Username BNE is the guy that does the testing.

Rickf1985
01-06-2022, 10:06 PM
Username BNE is the guy that does the testing.

https://castboolits.gunloads.com/member.php?29218-BNE

BNE
01-06-2022, 10:25 PM
Yep it's me. Shoot me a PM. I can help you out.

BNE

kevin c
01-06-2022, 11:34 PM
Doulos, if you get BNE to analyze your lead, please do us the favor of posting the result. It adds to the knowledge base here. (Which reminds me that I still have to prep a couple samples for him…)

gwpercle
01-07-2022, 01:35 PM
If you have a can of Drop Out Mould Release spray or a can of spray on Graphite ...spray your ladle , give it a good coat and let dry . The lead doesn't stick to the drop out coating and it last a fairly long time . This is a much better use than spraying the cavities of your moulds ... the stuff builds up on moulds and is a bugger to get cleaned off .
Works great to keep the ladle clean of dross build up ... do two coats , let dry in btween ...ladle stays clean a lot longe and dross doesn't adhere to it .
Gary

JonB_in_Glencoe
01-07-2022, 02:07 PM
25 degrees with a breeze. that's your problem.

Rickf1985
01-07-2022, 05:47 PM
You need to find out what alloy you have before cranking the heat up above 800 degrees or you could end up separating out your tin from the alloy. Then the next thing you know you are fluxing out your tin with everything else.

doulos
01-07-2022, 07:44 PM
Yep it's me. Shoot me a PM. I can help you out.

BNE
sent a PM

Forrest r
01-08-2022, 07:52 AM
As others stated you really should get it checked.

Myself, any time I'm not sure what I have I melt a little pit of it and waterdrop the melted alloy. If it stays soft I know it's pure or close to it. If it becomes harder from the waterdrop I know it's an alloy.

PBaholic
01-08-2022, 02:04 PM
I was given some lead. It was supposed to have been used as ballast weights for stage curtains etc. It is dead soft (about 4- 5bh with the pencil test). Thuds when you drop it and dents easily. It came in some big 40nlb chunks. It seemed like pure lead to me. So I decided to cast some .58 roundballs with it.

Pure Pb has a melting point of 620 degrees. Linotype (84% Pb, 12% Sb, 4% Sn) has a melting point of 480 degrees, which is the lowest of any alloy typically used in boolit casting.

You are likely still too cold.

Pure Pb will also not frost very easily when cast, and will have a dull darker grey color when exposed to the air for a while.

Your hardness test is key here. You can't get that low of a BHN if it's mixed with anything.

BNE
01-11-2022, 10:50 PM
You need to find out what alloy you have before cranking the heat up above 800 degrees or you could end up separating out your tin from the alloy. Then the next thing you know you are fluxing out your tin with everything else.

Sorry - I have to step in and correct this old wives tale. That theory is simply not true. I have done several tests over the years with very hot pots (~900F) and scraping the dross off the top. I kept samples from each scraping. Then I measured the alloy that was scraped off plus the final alloy.

THE ALLOY MIX DID NOT CHANGE!

I have done similar tests with a hot solder dip pot at work. It was left on for several years. (YES, YEARS) I tested that pot with the XrF that we have at work and I had samples sent out for a different style test method. The Tin content was NOT depleted at all.

Yes, the oxide layer on top of your pot contains Tin, BUT that is an incredibly thin layer. You are not going to "flux it out" with sawdust or wax. Nor will you "Over heat it out" or scrape it out.

BNE

Rickf1985
01-12-2022, 09:54 AM
That is good to hear, I was not sure on that. I was pretty sure it would not "Flux" out but not sure on the separation and then be pulled out with the flux. Do you have any info on whether the same is true if using real flux like the stuff you get from Frankford?
https://www.amazon.com/Frankford-Arsenal-CleanCast-Casting-Reloading/dp/B0063GSOK8

I have heard this will remove everything but the base metals under the right conditions. I use it once when doing me WW's but my temps never go above 750. After that initial flux with the Franford stuff I just use wax. Actually I just started trying wax before pulling out the clips and that has made a world of difference in how much easier it is to get the clips out without all the dross attached to them. If you have not tried it I suggest you at least try it once or twice.

jsizemore
01-12-2022, 09:38 PM
Very hot lead will have color. Depending how hot it can be gold, red, blue, or black. Since the melt temp of pure Pb is 629, your ladle is cooling quickly in your windy, 25degF weather. Keep the "dross" you've removed and remelt.

BNE
01-13-2022, 09:39 PM
I have not performed any direct test with the flux. The pot I talked about at work had a variety of professional fluxes used in it over the years. And it showed no signs of reduced Tin in the alloy.

BNE

JSnover
01-14-2022, 08:06 PM
Sorry - I have to step in and correct this old wives tale. That theory is simply not true. I have done several tests over the years with very hot pots (~900F) and scraping the dross off the top. I kept samples from each scraping. Then I measured the alloy that was scraped off plus the final alloy.

THE ALLOY MIX DID NOT CHANGE!

I have done similar tests with a hot solder dip pot at work. It was left on for several years. (YES, YEARS) I tested that pot with the XrF that we have at work and I had samples sent out for a different style test method. The Tin content was NOT depleted at all.

Yes, the oxide layer on top of your pot contains Tin, BUT that is an incredibly thin layer. You are not going to "flux it out" with sawdust or wax. Nor will you "Over heat it out" or scrape it out.

BNE

Thanks!
For years I've been telling myself the dross was probably high in tin and antimony, and re-melting it to recover 'the good stuff.' Some Old Guy told me that, back when I was Some Young Guy.