Can you burn lead??
- Thread starter Dave.S
- Start date
- Location
- Western Manitoba
I do not know about a substance - all was crap that fluxed out when I smelted mine - but I did learn that I can get lead "too hot" - had rolls of soft lead from lining in former dentist office x-ray room - thinking I was "smart", I used propane torch directly on the sheet lead to melt that and dribble into melting pot - ingot got skin of golds and various colours - apparently the flame of torch made that lead "too hot" and the colours are from oxidizing it. I must have made more than 40 one pound ingots that turned out like that - could not "skim it off" - it simply re-formed on the surface.
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You probably have some impurities in it. Once you flux and stir the flux you should be able to remove it from the top of the melt.
Lead will not 'burn' in the conventional sense but it will start to vapourize above 750 degrees F and will boil at about 1750 degrees C.
That looks like zinc got mixed in......no good for dripping shot,I have never had success casting bullets with it either....I have tried everything too.."skinning the top"..it will never go away..I have deluded it with pure lead with some success for shot making,it just depends how much zinc I got in the batch
- Location
- Western Manitoba
zinc contamination - I had bought some ingots from CGN - had "blotchy" to them - some shiny areas, some dull - was my belief they contained some zinc. For sure, in sorting wheel weights, I found some with "Zn" mark on them. Really crude, but if I dropped ingot (Edit - a typo - I dropped the individual wheel weights, not ingots) on concrete floor and got a "thud" - I presumed that was okay - but if I got a "ringing" sound, I presumed that was from zinc contamination. For my own "smelting", I had a Lyman casting thermometer in the pot - would get the melt just hot enough to melt lead, but not hot enough to melt zinc - so was lots of crud and crap would get skimmed off, when fluxing that. I don't think is normally possible to remove zinc once it gets alloyed in with the lead, so I was thinking that I had to do that sorting at the start - no coming back from mistakes. I, and others, not so sure how significant an issue that zinc contamination is for making up "blasting" ammo. As done by at least one other guy on CGN - I sold off all my casting stuff and supplies and simply buy what I want from Jet Bullets - certified foundry alloys, so is no "guess work" what is in them.
I must say I was sort of "shocked" to read of "eutectic alloys" - so take lead and tin, for example - each parent metal has a melting temperature. Alloy them together - when using a "eutectic" proportion or ratio, the result will be an alloy that has a LOWER melting temperature than either parent metal - so the notion that one can heat up the alloy just enough to melt the lead, but not the zinc - does not seem to be "real", if the two were actually alloyed in the first place. The stuff will be liquid many dozens, or in some cases, hundreds, of degrees before getting to lowest melt temperature of either parent metal - unless I have that all muddled up ...
I must say I was sort of "shocked" to read of "eutectic alloys" - so take lead and tin, for example - each parent metal has a melting temperature. Alloy them together - when using a "eutectic" proportion or ratio, the result will be an alloy that has a LOWER melting temperature than either parent metal - so the notion that one can heat up the alloy just enough to melt the lead, but not the zinc - does not seem to be "real", if the two were actually alloyed in the first place. The stuff will be liquid many dozens, or in some cases, hundreds, of degrees before getting to lowest melt temperature of either parent metal - unless I have that all muddled up ...
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Bassmaster
CGN frequent flyer
- Location
- WMU 48 - Whitetail country
This...
Try a different flux and scoop it off. I vary between fluxes, from wax to saw dust, and have also tried stirring the pot with a wooden paint stir-stick
i know that you will get different sounds if you drop a lead WW vs. a zinc WW but I think that unless the zinc % was really high the sound generated by a lead WW ingot vs. one contaminated with zinc would be indistinguishable.
I have Linotype bars that ring when hit. Excellent metal to harden your alloy up with. Also happens with Babbitt bars so not really a sign of bad alloy. A 25 lb bar of Linotype rings like a tunning fork,beautiful sound.
zinc contamination will give you the blue cobalt like colour like on the top right ingot in the picture.
With zinc in the mix it won't flow nice like you'd have with molten lead.
Do yourself a favor and buy a pid controller to check the temperature in your melting pot. Use the propane torch to heat the pot on the outside, don't torch the lead directly.
Keep the temp right and all the zinc weights can be scooped from the top.
tip: stainless mesh strainer works better for scooping slag or contamination/impurities off the top than a slotted spoon.
With zinc in the mix it won't flow nice like you'd have with molten lead.
Do yourself a favor and buy a pid controller to check the temperature in your melting pot. Use the propane torch to heat the pot on the outside, don't torch the lead directly.
Keep the temp right and all the zinc weights can be scooped from the top.
tip: stainless mesh strainer works better for scooping slag or contamination/impurities off the top than a slotted spoon.
- Location
- Western Manitoba
bertn - your post is the first that I read that zinc can create colours - I did not know that - as mentioned, that picture showing coloured ingots in Post #2 was simply melted soft sheet lead - was not from smelting wheelwrights. And re-reading what I wrote in post #6 - it was the wheel weights that I would drop on the floor to hear the different sound - not the whole ingot - I just added an "Edit" to that post. Someone came around and took the ingots and my casting gear off my hands - so I do not play that game any more - as mentioned, I just buy what I want from Jet Bullets - 485 grain for 458 Win Mag, and 285 grain for 9.3x57. Is a bunch of cast, lubed and gas checked .314" here - likely for 303 British or 7.65 Argentine - I suspect was my product from wheel weights - is yet to be fired off.
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vagrantviking
CGN Ultra frequent flyer
- Location
- High River, Alberta
I agreed that in my experience the colours are common on pure lead ingots or the melt in the pot.
Wheel weight is much less likely to look like that. I haven't noticed it in batches that I suspected contamination in either but have not experimented with zinc on purpose.
The pid controller is a great way to keep temperatures from getting away on you but a simple dial thermometer is good too.
Wheel weight is much less likely to look like that. I haven't noticed it in batches that I suspected contamination in either but have not experimented with zinc on purpose.
The pid controller is a great way to keep temperatures from getting away on you but a simple dial thermometer is good too.
And lead vapour is not something you will want to be inhaling.
Umm, fumes occur about 930°F/ 500°C
This is how my big melting pot looked the next day after overheating it a lot and melting in zinc wheelweights during my first ingot making adventure.
Ended up selling the ingots to a scrap metal place and got a good price for them so all good in the end lol.
Had gotten a pid controller and had a hard time getting the pot at the right temperature, turned out the thing was set to celcius instead of Fahrenheit
the blue and purple colours were really bright and pretty.
Ended up selling the ingots to a scrap metal place and got a good price for them so all good in the end lol.
Had gotten a pid controller and had a hard time getting the pot at the right temperature, turned out the thing was set to celcius instead of Fahrenheit
the blue and purple colours were really bright and pretty.
When I worked in a glass bottle making factory, we would bring in scrap glass of all colors.
Of course, other than for amber or champagne green, we had to separate all of the colors and blend the scrap glass accordingly.
When we ran Champagne Green, many of the bottles came in full, with labels, wire and lead wrapping intact. This happened a couple of times per year, for all sorts of reasons, such as the government banning imports from recently designated nations. One of them was South Africa, during Aparthied.
We had to be careful when walking under the melting furnace floor, while doing inspections. Those furnaces were heated to 1750F to melt such dark glass. The lead foil would melt, sink through the molten glass to the floor of the furnace and in such a high heat the viscosity of that lead was similar to penetrating oil
The glass would just solidify as soon as the ambient air hit it, but the lead would just keep on flowing. A fellow could get a super nasty burn from those falling drops of lead, especially if it hit the top of his "plastic" helmet.
I used to put metal pots on the floor, where the leaks usually occured and collected the lead. I would get 20-30Kg every six or so months.
That lead was fantastic stuff. Absolutely pure, shiney and dead soft. Ideal for round balls, requiring patches.
Even at those temps, there weren't any impurities in that lead and it was very shiney, without any discoloration, which is seen in the pics above.
I agree with the other comments. If you are getting granular bits, it's definitely impurities, such as dirt or even zinc.
Of course, other than for amber or champagne green, we had to separate all of the colors and blend the scrap glass accordingly.
When we ran Champagne Green, many of the bottles came in full, with labels, wire and lead wrapping intact. This happened a couple of times per year, for all sorts of reasons, such as the government banning imports from recently designated nations. One of them was South Africa, during Aparthied.
We had to be careful when walking under the melting furnace floor, while doing inspections. Those furnaces were heated to 1750F to melt such dark glass. The lead foil would melt, sink through the molten glass to the floor of the furnace and in such a high heat the viscosity of that lead was similar to penetrating oil
The glass would just solidify as soon as the ambient air hit it, but the lead would just keep on flowing. A fellow could get a super nasty burn from those falling drops of lead, especially if it hit the top of his "plastic" helmet.
I used to put metal pots on the floor, where the leaks usually occured and collected the lead. I would get 20-30Kg every six or so months.
That lead was fantastic stuff. Absolutely pure, shiney and dead soft. Ideal for round balls, requiring patches.
Even at those temps, there weren't any impurities in that lead and it was very shiney, without any discoloration, which is seen in the pics above.
I agree with the other comments. If you are getting granular bits, it's definitely impurities, such as dirt or even zinc.
- Location
- Western Manitoba
Is good information - you experienced lead heated to 1750 F that was shiny, without discolouration - as per Google just now, "Propane fuel has an in-air flame temperature of 3,600 degrees Fahrenheit" - so is what I was playing against that lead sheet metal - a propane plumber's torch - going "full blast". I have no clue how hot it actually got, but seemed to melt the lead away pretty fast. I still have not found another reference what contaminant can be added to molten lead to create gold and blue colours, over and above overheating it - in my case, maybe three thousand degrees F beyond melting point. I had cut up the sheet lead into about 3 foot lengths - so, perhaps 4 feet wide - rolled up to be perhaps 6" diameter by 3 feet long - is what I was melting into my heated smelting pail. The ingots shown in Post #2 are what I ended up with. I did flux using liberal amounts of sawdust from a power miter saw - and a "stir stick" from a piece of poplar fire-wood. That stick charred up pretty good.
I've heard many theories of why it happens and in the last 10 years as the use of zinc wheelweights has increased, much as been blamed on zinc, including these colours.
However, golden and "rainbow" colours are not indications of zinc. Any lead alloy, including pure lead will attain that colour (on the surface only) if heated well above meting temperature.
Remelt it at a lower temperature and it will disappear.
However, golden and "rainbow" colours are not indications of zinc. Any lead alloy, including pure lead will attain that colour (on the surface only) if heated well above meting temperature.
Remelt it at a lower temperature and it will disappear.
fingers284
CGN Ultra frequent flyer
- Location
- Alberta Cowboy Ranges
Concurs with what I was told by the old boys on CB when i inquired as to "why my pure lead ingots have gold hue to them"
