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View Full Version : Some kind of babbit, or what?



fatelk
12-26-2010, 08:12 PM
I have three big bricks of mystery lead that I've had for a couple years, assumed it was wheel weight lead or something. I decided today to melt it into ingots.

They weigh about 25 lbs each and won't fit into my 20 lb Lee pot, so I did what I usually do in this kind of case; I sat one on top of the pot and heated it with a propane torch so it would drip and melt into the pot.

I was surprised when it melted very fast, and the sides that were sitting on the top of the pot began to melt too, and drip down the side. It melts at a much lower temp than any lead I've ever had. When I pour it into ingots, it takes an incredibly long time to solidify. It also has a very crystalline surface.

It is pretty hard. I don't have a hardness tester, but I would bang a known ingot against the brick before melting to get an idea of hardness, and it seems about as hard as linotype. I weighed the ingots dropped from the Lee ingot mould. They normally weigh right at one pound with WW lead, and with this stuff they are about 14 ounces.

1. Melts at a low temp
2. about 88% of the weight of WW lead
3. hard like linotype

What is this stuff? Babbit or something else?

madsenshooter
12-26-2010, 08:42 PM
Probably so, most of it is 23BHN, but content varies widely depending on whether it is tin or lead based.

fatelk
12-26-2010, 09:37 PM
My thermometer isn't very good, but as far as I can tell it looks like this stuff melts below 300 degrees. It's hard to tell because my pot doesn't go down that low. I added cold metal and watched it melt while the temp dropped.

If this is good metal I'll need to figure out what it's worth and maybe sell it. I'm a bit tin rich and lead poor at this point.

lwknight
12-26-2010, 09:53 PM
If it melts below 300 degrees , you probably have some bismuth in it.
It would make good trade fodder to the right buyer. Low temp alloys are kinda pricy

felix
12-26-2010, 10:19 PM
Good observation about the bismuth. Prolly so because of the hardness and weight of the "babbit". Does not appear to be tin based unless the bismuth content is high to compensate for the weight. Would be interesting to add to WW at 10 percent and do a shooting contest between WW and the new WW mix. ... felix

fatelk
12-26-2010, 10:28 PM
I was watching the thermometer (wish I had a more accurate one), and this stuff seems liquid down to 200F or less.(!?!?)

I'm guessing it's worthless for boolits, but I looked up "Low Melting Point Bismuth Based Alloys" on the Rotometals site, and it's really expensive stuff if that's what it is.

I have about 75 pounds of it. Does anyone know how to tell for certain what it is, or the best way to try to sell it?

fatelk
12-26-2010, 11:22 PM
This is some weird stuff! I let it cool down until my thermometer read about 150F (again, not a real accurate thermometer). It was still liquid with crystals starting to form on top. Out of curiosity I dripped a little water on it, then a little more. The water just puddled on top of the liquid and solidifying metal, no boiling, bubbling or anything.

From looking around a bit it appears to be Cerro-bend or Cerro-safe. I'm guessing Cerro-bend as it doesn't come out of the ingot molds very easy, have to tap it a little bit.

runfiverun
12-27-2010, 02:17 AM
they still use bismuth/tin alloys on some fire sprinkler heads. it was used exclusively on the older ones.
they would melt and the insides would be pushed out by the water pressure.
they could be had in ranges from 140* up to over 240*.
it was also used for links in a chain on fire suppression hoods which when broken [melted]
would allow the chain to pull back and set off the suppression system....

anyways i'd only use about 3-5%.
bismuth is pretty brittle, tin is used to take the brittleness out.
bismuth shot is 5% tin or it will shatter on target and from the set back in the case when fired.
but it's heavy and adds hardness to a lead alloy about like antimony.

rob45
12-27-2010, 02:44 AM
This is some weird stuff! I let it cool down until my thermometer read about 150F (again, not a real accurate thermometer). It was still liquid with crystals starting to form on top. Out of curiosity I dripped a little water on it, then a little more. The water just puddled on top of the liquid and solidifying metal, no boiling, bubbling or anything.


If your thermometer is reading 150 and dripping water has no effect, you know that the alloy is not yet at 212 F.
Remember, water does not boil until 212 F. It also pooled on top of the alloy due to the fact that water is less dense than the metal.

So what was the purpose of dripping water on it? Just wonderin'.

fatelk
12-27-2010, 12:56 PM
So what was the purpose of dripping water on it? Just wonderin'.
I don't entirely trust my old thermometer, and wanted to see if it was really still liquid below 212F.


Remember, water does not boil until 212 F. It also pooled on top of the alloy due to the fact that water is less dense than the metal.
I thought this went without saying. If I didn't know these very basic things I would have no business playing with molten metal.:)


I thought the crystalline surface that formed as it cooled looks neat.

rob45
12-27-2010, 01:20 PM
No problem, fatelk. Like I said- just wonderin'.:drinks:

If I'm concerned about a thermometer, I use a freeze test and calibrate it.

Any luck figuring it out? I think LWK had a good idea concerning the bismuth.

fatelk
12-27-2010, 03:52 PM
I'm not familiar with a freeze test, but that gave me the idea to test it in boiling water. It seems to read a little low, so I think the metal was in the vicinity of 170F when it had crystals starting to form on top.

Yes, I'm pretty certain it's a bismuth alloy. Based on it's properties and what I've found looking around on the internet, I think it's something similar to this: http://www.rotometals.com/product-p/lowmeltingpoint158alloy.htm

Not cheap stuff. Now I just need to figure out how to tell for sure and how to sell it. If it won't make boolits it won't do me much good. If I can sell it for even a good fraction of what cerro-bend sells for I will be very happy.

lwknight
12-27-2010, 08:07 PM
Fatelk, you should build your self a mold to make spoons out of that stuff. When you have company , give them a spoon that will melt off in the hot coffee. Tell then its strong coffee to get the fun started.

rob45
12-28-2010, 04:13 PM
Fatelk, you should build your self a mold to make spoons out of that stuff. When you have company , give them a spoon that will melt off in the hot coffee. Tell then its strong coffee to get the fun started.

Now that's a good one!

"Pitch a horseshoe in there and see if stands up."
"I don't have a horseshoe, but I have a spoon."

[smilie=l:[smilie=l:

fatelk
12-28-2010, 06:00 PM
That is pretty good. For kicks I think I'll take a small piece of it and see if it melts in a cup of hot water.

rob45
12-28-2010, 07:08 PM
Hey fatelk, I just checked your link to the Rotometals site.

If it is something close to Woods metal, remember that it could also contain cadmium in it.
I'm sure you may have already taken this under consideration; just don't want you gettin' hurt if you didn't.

If you don't conclude anything with your search, maybe Rotometals or some similar supplier could help you out. They may offer to do a free analysis for you if it's something they sell or deal with and you give them dibs on it. Not sure, but worth checking out.

At any rate, that is a bunch of "specialty" alloy!

JIMinPHX
12-28-2010, 07:16 PM
That might be some potting compound like machinists use to set odd shaped parts in so that they can be held in a mill vice.

Wayne Smith
12-28-2010, 09:10 PM
Remember you can send a sample to Rotometals for analysis. Then you would know what you have.

Typecaster
12-28-2010, 09:36 PM
Potting compound
Haven't heard of that in a loooong time.

I have half a pail of Wood's metal foundry ingots. They do easily melt in boiling water. Looks weird to see molten metal in a pot with water on top…

I was thinking of making a cast metal plate to go at my gate with the house number on it. Maybe make a plaster of Paris mould and use up some of that cadmium-rich alloy. Otherwise, I'll just use it like Cerro-bend.

I just picked up 2 ingots of Cerrocast alloy. Don't know what I'll use 'em for, but that kind of stuff is pretty pricey if you look at McMaster-Carr, etc.

Richard

Richard

lwknight
12-28-2010, 09:40 PM
Remember you can send a sample to Rotometals for analysis. Then you would know what you have.

Yeah , for $69.00 a pop. It would be cheaper to just resell the metal to a recycler unless you had a couple hundred or more pounds of it.

fatelk
12-28-2010, 11:12 PM
Maybe I'll contact rotometals to see if they would be interested in it. I wonder if they bother with quantities this small. I doubt that a local recycler would give me anything for it.

My other thought was to sell it by the ingot on ebay. I could sell it for a lot less than what similar metal sells for there and still come out very well.

As to cadmium, I did see that, and have been careful around it.

Dang, just looked up cadmium toxicity; nasty stuff. I guess I won't make any spoons out of it for folks to stir their coffee with.:) I don't think I had too much exposure. I just melted it down and made ingots, using the usual precautions as for lead.

JIMinPHX
12-29-2010, 12:05 AM
You might want to keep a little of it around for making chamber castings.

nanuk
12-29-2010, 08:18 AM
what Jim sez

see if you can melt some in boiling water.

then, take a metal tube and pour some in.

after it hardens, see if you can get it out.

some alloys shrink. others enlarge.

I have some I use to lock a barrel in the vice.

the stuff I have is opposite of cerrosafe.

badgeredd
12-29-2010, 08:46 AM
http://www.midwayusa.com/viewProduct/?productNumber=462291

If it is a Cerrosafe this will give you a hint of its value.

Edd

fatelk
12-29-2010, 02:32 PM
Thanks everyone for the ideas.

I suspended a small piece in a pan of water and heated it up while watching it with a cooking thermometer. It melted at 170 F.

I then cut a piece of 3/4" stainless high-purity tubing (polished interior), plugged the bottom, and filled it with this stuff. After it cooled for a few minutes I tapped it out. I got it out, but it did not come out easy.

My understanding is that that cerro-safe can be used for chamber casting because it will shrink slightly for the first half hour, allowing it to come out of the chamber easily, whereas cerro-bend can be used to fill tubing for a clean bend; it does not shrink while cooling so would not work well for chamber casting.

Seems like I read somewhere in my reading on this in the last couple days that one could add a little lead to cerro-bend to use it as cerro-safe, but it was important to do it precisely.

Based on what I see, I think this is a cerro-bend type alloy. I called roto-metals and they do buy it. I can send him a small sample for a price quote, but he estimated somewhere around $4/lb.

I could probably get a better price by melting it all into ingots and selling it on ebay or something, not sure if it would be worth it or not. I saw similar stuff sold there for $15 for 1.5lbs, plus $10 shipping. (!) I could sell it for less, and half the shipping, and do OK.

Added: definitely not cerro-safe! According to that Midway link, cerro-safe is supposed to shrink nearly a thousandth in the first half hour. It's been a half hour. I just measured it and it has grown two thousandths!

Good for bending tubing and holding small parts to machine - Yes
Good for chamber castings? NO