"18/10" stainless?

I'm planning to make my own crucible for the Gingery foundry. I found a

1 qt stainless steel sauce pan at WalMart that was just about perfect except for the fact that it was $15. (I am SO cheap!) Then I found one that was just $5--that's more like it! But the $5 one said it was "18/10 stainless steel". What does that mean? Is that some kind of steel/aluminum mixture or something? And, cutting to the chase, is it going to melt if I use it as a crucible?
Reply to
PhysicsGenius
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After some keyword massaging, Google found this:

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So "18/10" stainless is just plain stainless? I guess it's a marketing thing. Pff.

Well, it sounds like the $5 pan is the > I'm planning to make my own crucible for the Gingery foundry. I found a

Reply to
PhysicsGenius

Reply to
Roy J

It's an ordinary austenitic stainless, like 304. It contains chromium and nickel. Will those alloy with aluminum? I don't know. But iron will, and I don't know, either, if the chrome or nickel will prevent the iron in the stainless (70%, roughly) from alloying with the aluminum.

It probably won't melt (it melts at 100-200 deg. F lower than mild steel), but it probably will warp like hell.

I wouldn't do it. That's pretty thin steel for the job. I like Gingery's solution of a steel pipe with a cap welded on it, with a wash of thinned-out fireclay to prevent iron pickup. I haven't tried it, but it sounds good.

Ed Huntress

Reply to
Ed Huntress

I like his solution too, but I don't have access to a welder. And the only place I can find threaded pipe that wide is online and it's ~$15 (endcap included) before shipping.

Reply to
PhysicsGenius

Reply to
PhysicsGenius

Reply to
Roy J

Then why bother to call it 18/10 and not just "stainless" ?? the old term

18/8 meant 18 percent chromium and 8 percent nickle, now commonly called 303. 18/10 is also common, now called 304, and better for welding than 303.

I can't imagine anyone melting iron safely without proper tools and crucible.

Reply to
bw

Are you talking to me? Because I'm melting aluminum, not iron. What's the upshot here? I can't use it because it might not be solid stainless, but I *can* use the $15 one (I guess I could buy the $5 one and use Archimedes to tell me if it's solid steel...). Or should I not use stainless at all? I'm a shoestring here.

Reply to
PhysicsGenius

"I'm a shoestring." I wish. I'm ON a shoestring.

Reply to
PhysicsGenius

I've used stainless household containers as crucibles for melting aluminium (and brass) and the results are so-so.

Works OK, but "crucible" life is pretty limited. Pinholes develop pretty quick. The thin-walled stainless is pretty delicate. A big ugly welded pipe crucible works better.

Jeff

Reply to
A.Gent

No it's not.

18/10 refers to a stainless with nominally 18% chromium and 10% nickel, as the alloying elements in combination with iron. Abrasha
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Reply to
Abrasha

I forgot to add, that for instance there is also 18/8 stainless (18% chromium and 8% nickel). And several other varieties.

There is no such thing as "plain stainless" steel. Generally stainless steels fall into two large goups, i.e. austenitic grades which are not heat treatable, and the martensitic grades, which you guessed it, are heat treatable.

There are many varieties, each one with very different copmpositions and properties than the next one. Here is a list. I don't know if it's complete.

321 330 347 403 409 410 (S, HT) 416 (HT) 418 (Greek Ascoloy) 420 420F 422 430 431 439 440A 440C 440Fse 446 AM350 AM355 13-8MO 15-5PH 15-7MO 17-4PH 17-7PH 19-9DL301 (all tempers) 302 (B) 303 (Se, B) 304 (L, B) 304LVM309(S) 310(S) 316 (L, B) 316VM 317 (L) 317VM Duplex Stainless F-255 2205 A286 Alloy 20 Nitronic 30 33 40 50 60 Jethete M-152 Custom 450 Custom 455 Abrasha
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Reply to
Abrasha

Not true. Not "any" of the 300 series are 18/10, only "some" of the 300 series are.

301 has 16-18% Chromium and 6-8% Nickel 330 has 19% Chromium and 35% Nickel 333 has 25% Chromium and 45% Nickel etc.

Abrasha

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Reply to
Abrasha

If I am not mistaken, and I very well might be, one should not use a metal crucible to melt metal, but rather a ceramic or clay crucible.

Reply to
Abrasha

Plain mild steel (ok, so they have a few microns of tin plate) soup cans (specifically the nice big 4" dia. ones) work perfectly fine for me. Good for two or three melts if you don't overheat it.

Although lately I don't use any at all, I like my reverb furnace :)

Tim

-- "That's for the courts to decide." - Homer Simpson Website @

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Reply to
Tim Williams

Don't melt aluminum in plain steel if you want the best mechanical properties in the aluminum. It will alloy with iron, and the result becomes increasingly brittle and weak as you get more iron into the alloy.

A simple way around it is to thin out some fireclay and slosh it around the inside of the steel crucible. Then let it dry. I haven't tried this but people who have say that it works just fine.

If you're going to continue to use soup cans to melt aluminum, make sure you have good insurance and that the insurance company doesn't know what you're doing in your spare time.

Ed Huntress

Reply to
Ed Huntress

An 18/10 cook pan from K Mart is perfectly safe for melting aluminum.

That is, if you take three days to bring it to temperature!

And even then, I am not so sure.

A more suitable "crucible" is a stout piece of pipe and a cap.

My senior project at ODU: Google Groups, then "dgoncz" and some of: ultracapacitor bicycle fluorescent flywheel inverter Equipped with BoBike Mini removable child seat, too!

Reply to
Doug Goncz

Reply to
Roy J

So Mr. Shoestring, you gotta make friends at the local scrap yard. I agree with others here about a big ugly pipe with a plate welded on one end. We made ours out of 4" pipe, and when they wear out they can be easily replaced (unless they stop making 4" pipe). The reason is that our removing-tongs and pouring-tongs are both custom made (roughly like Daves) to fit. It's easier to make a new crucible than tongs ... Also, we use ours unwashed, so apparently we end up with some aluminum that has a bit more iron in it than it's supposed to. Having said that the Gingery lathe has been working for years with no casting failures.

I'll bet that if you find the right scrap yard and pick a good time to visit, you may be able to get them to cut and weld up a few crucibles from scrap for very little money. I'm Scottish by heritage, so a bit of a Shoestring myself :)

Reply to
Dave Keith

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