What did I put in my pot

[tcrocker]

I got what I thought was some free lead, some of it was roofing lead and some of it was already melted in blocks. The roofing lead melted fine but the other stuff I had to turn up the heat but it never poured right it cooled very fast and was hard as a brick bat. It also left a skin on top and turned purple green and other colors you could see that the molten metal was not mixing well it even stuck to my dipper. Does any one have any ideal what I put i my pot I think I my just need to through the hole pot away.

[Walter Laich]

when you said turn up the heat--how high did you have to go from your regular temp?

[lwknight]

You really need a thermometer.
Lead blocks are hard to melt. Roof jacks/boots have tin in the joints that lower the melt temperature.
Pure lead will make all colors on top when it gets too hot.
Maybe it was lead with antimony in it?

Repeat after me: I will get a thermometer!

[CGT80]

Pics would help.

I use this thermometer: http://www.teltru.com/p-272-big-green-egg-primo-grill-dome-kamado-replacement-thermometer-lt225r-5-inch-stem-2001000-degrees-f.aspx

I now run a PID on my lee 20 pot, but I still use the thermometer to smelt my lead. Side cutters will quickly show you what is zinc and what is lead. If you had a small chunk of the material in question, or maybe even just the corner of it, you could try to cut it. Lead wheel weights, roofing lead, sheet lead, etc. will cut easily. Zinc wheel weights are nearly impossible to cut. Soft lead has a thud when it lands on concrete. Zinc has a nice ring to it, but lead with a decent amount of tin and antimony will also ring, as well as linotype.

Pure lead takes more heat than alloyed lead like wheel weights. Zinc takes even more heat than pure lead, but it will still melt in an electric pot or over a propane burner. My smelt got up to 1,000 degrees over the propane. Luckily I sorted the wheel weights so I didnt' have zinc. I did get rainbow colors when I got the pure lead real hot. Acid will also fizzle or bubble on zinc. I think I have pool acid. You can do a search here for zinc tests. I keep a zinc wheel weight to compare the bubbling to other material. Lead doesn't bubble from the acid, but sometimes the surface can be dirty and it will give a false positive. Some of my ingots had cement material on them. That really made it bubble.

[243winxb]

it even stuck to my dipper. It does if dipper is cold. Use maximum heat, flux, cast. Check weight of bullet & diameter. This will tell you something. Pure antimony will not melt in a Lee casting pot, temperature is to low.
Quote:
The bullet diameters and weights presented in this list
are based on the use of Taracorp’s Lawrence Magnum
bullet alloy (2% tin, 6% antimony, 1/4% arsenic,
91.75% lead).
Bullet diameters and weights will vary considerably
depending on the lead casting alloy used. This variation
can be as much as 1/2% on the diameter, and 8% on
the weight among the most commonly used casting
alloys. For example, a .358-158 grain bullet might
show a diameter variation of .002", and a 13 grain difference
in weight.
Of the most commonly used alloys, wheel weights (.5%
tin, 4% antimony, 95% lead) will produce bullets having
the smallest diameter and heaviest weight, with
such bullets running approximately .3% smaller in
diameter and 3% heavier than bullets cast with
Taracorp's metal. Linotype will produce bullets with the
largest diameter and lightest weights. This alloy will
produce bullets approximately 1/10% larger and 3%
lighter than Taracorp. Other alloys of tin and antimony,
with antimony content above 5%, will produce bullets
with diameters and weights falling between those cast
from wheel weights and linotype.
Alloys containing little or no antimony will cast considerably
smaller than wheel weights and in some cases
will produce bullets too small for adequate sizing.
Within the limitations given above, the weight and
diameter of a cast bullet can be adjusted by varying the
alloy’s antimony content.
The size and weight of bullets of a given alloy will also
vary according to casting temperature. Higher temperatures
will result in greater shrinkage as the bullet
cools, thereby producing a slightly smaller and lighter
bullet than one cast of the same alloy at a lower temperature

[jmort]

What pots can melt antimony? I don't think any of the common pots can, including Lee Precision

[Echo]

I read an article once that showed some gents melting Sb in a pot over a charcoal fire with a blower to provide more air. As I remember, when it went full melt, it glowed a dim red that one could see if they shaded their eyes from the sun. Once it was melted, they alloyed it with pure Pb, the resulting alloy being used to generated the final alloy, being easier to melt at lower temperatures.

[runfiverun]

antimony melts around 1200-f airc.
the super hard and high melt temp indicates something other than lead.
lead, plain lead, has a higher melt temp than the common alloys made with it does.

[RogerDat]

I have to thank 243winxb for that succinct quote on shrinkage. Been reading the reviews on Lee .312 185 gr. and saw someone comment that negative reviews for casting undersized was probably due to mistake made in casting. Wondered what that mistake was, now I know. Cast too hot and it shrinks more.

runfiverrun makes a good point, pure lead has a higher melt temp. than lead with common alloys in it. So most alloys that increase hardness will decrease melt point. This page has a table with different solder alloys and melt temps which may help you identify what alloy is by melting temp. http://en.wikipedia.org/wiki/Solder

[tcrocker]

I have no ideal on temp I use a turkey cooker and a cast iron pot.

[wgaynor]

I have to thank 243winxb for that succinct quote on shrinkage. Been reading the reviews on Lee .312 185 gr. and saw someone comment that negative reviews for casting undersized was probably due to mistake made in casting. Wondered what that mistake was, now I know. Cast too hot and it shrinks more.

runfiverrun makes a good point, pure lead has a higher melt temp. than lead with common alloys in it. So most alloys that increase hardness will decrease melt point. This page has a table with different solder alloys and melt temps which may help you identify what alloy is by melting temp. http://en.wikipedia.org/wiki/Solder


HAHAHA You said shrinkage... reminds me of that Seinfeld episode! :grin:

[RogerDat]

HAHAHA You said shrinkage... reminds me of that Seinfeld episode! :grin:

No, not the same at all. As I understand it a dip in cold water makes cast bullets harder not smaller. :-)

[HollandNut]

I gots a thermometer if ya wanna borrow it