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View Full Version : An Explanation of The Plus Metal Buy



wiljen
06-09-2007, 04:27 PM
I have been working with a custom lead fabricator (makes all kinds of stuff for hospitals/nuke plants etc) to come up with an alloy that could be used to enrich the readily available alloys and produce some others that are either hard to get, costly, or both.

Most of us can find Lead and / or Wheel weights at reasonable prices. Any other alloy can be scarce or pricey.

I started out looking for a way to turn Lead into WW alloy. I used the assumption that Wheel weights were 95% Pb, 4.5% Antimony, and .5% tin. My own preference is to add tin to bring the total to roughly 2% as I think it improves casting and is still cost effective. I started out looking at an alloy of just tin/antimony/arsenic but was told by the foundry that it wasn't an alloy they could do. They also suggested that any alloy with the percentage of Antimony I was requesting would have a melting point above the maximum I had specified (approx 700). The best alloy for this purpose turned out to be the 47% Antimony ,37% Lead, 18% Tin (with trace (.2%) arsenic). It would melt within the temp range specified, would add sufficient Antimony and tin to match WW+1% and had arsenic so heat treating would be possible.

Combining 1 lbs of the Metal+ alloy to 10 pounds of lead yields an alloy with 94.3% lead, 4.3% Antimony, and 1.4% tin. I ran some initial tests and there is enough arsenic in the alloy to allow hardening when used in this manner. So we now have a way to make WW alloy from pure lead.

I then looked at using the same alloy to enhance WW.

1:10 yields an alloy with 89.7% Lead, 8.3% Antimony, and 2% tin. A quick check of alloys shows this to be equal to Taracorp's Magnum Alloy.

2:10 yeilds an alloy with 85% Lead, 3.4% Tin, and 11.6% Antimony. An alloy that should sound suspiciously like Linotype (2.25:10 makes an almost perfect Lino).

6:10 Makes Monotype and if you really wanted to carry this to extremes 1:1 makes roughly Foundry type.


As you can see, the metal is useful to enrich scrap range lead, WW, or soft scrap into the harder to find and more expensive alloys.

This means you can use whatever is available and not have to swap lead for WW or pay high prices a pound for lino.

I think we got a heck of a deal on this as the foundry certifies the %s and casts it into bricks. I can pick it up from his dock so we pay no shipping except from me to you guys. The cost on it is $4.00 a pound which I think is exceptional with lead alone being over $1 right now.

lathesmith
06-09-2007, 11:05 PM
Wiljen, does the foundry stamp the metal content on the bricks? I find this can be important, if I later sell some of my metal to fellow casters they don't just have to "take my word for it" as far as the contents of the bricks go. Also, I don't have to keep track of what's what--I have a pretty good variety of metal in my stash, and such stamping would also be helpful for this reason.
Lathesmith

Ernest
06-09-2007, 11:45 PM
I'll take 10 lbs/ changed my mind I want 25 lbs

wiljen
06-10-2007, 08:42 AM
Wiljen, does the foundry stamp the metal content on the bricks? I find this can be important, if I later sell some of my metal to fellow casters they don't just have to "take my word for it" as far as the contents of the bricks go. Also, I don't have to keep track of what's what--I have a pretty good variety of metal in my stash, and such stamping would also be helpful for this reason.
Lathesmith

I haven't ask but will contact them Monday and see if they will do that for us.

charlie / sw mo
06-10-2007, 09:42 AM
ill take 25 pounds. are these one lb ingots or larger ? 65759

charlie in sw mo

Buckshot
06-10-2007, 10:23 AM
............I'd be in for 25 lbs too.

............Buckshot

Ernest
06-10-2007, 11:55 PM
What is foundry type. How hard would it be if you heat treated it?

wiljen
06-11-2007, 06:21 AM
What is foundry type. How hard would it be if you heat treated it?

Foundry Type:

62% Lead
23% Antimony
15% Tin

I suspect that a full heat treatment would reach the 40s in BHN but would be so brittle as to explode upon hitting anything. Some of the others here with more experience may know better than I but I suspect its use in casting would be limited to 1 part of foundry into 10 of something else.

cohutt
06-11-2007, 06:45 AM
I (think) i placed an order for 30lbs. MO to follow.

Using Antimony man's prices (from memory) for the individual components this works out to be a 40-50% discount, plus in a manageable alloy (ie no toxic antimony dust).

Not a bad item to have in the alloy inventory.