"18/10" stainless?

After some keyword massaging, Google found this:

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

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

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.

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

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

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.

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

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

No it's not.

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.

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

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.

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 @

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

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!

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 :)