Stainless Steel Questoin

[Kim]

So I'm looking at Stainless right now for a possible future project, but I don't have much experience with it.

I've mostly heard people saying that 303 is the best stuff to use.  But On Line Metals also has something they call "304/304L ANNEALED".  Is that better than "Cold Drawn 303"?  The 304 seems to be a bit less expensive than the 303, but if its harder to work with, its probably not worth the savings.

Does anyone have any advice on 303 vs 304?  Or are they fairly equivalent?

Thanks,
Kim

[Thor]

Hi Kim,

 304 is an austenitic Cr Ni stainless steel (18/8), and I find it more difficult to turn or mill than the freecutting 303 grade. If you are going to turn the stainless steel my advice would be 303.

Thor

[crueby]

Hi Kim,

 304 is an austenitic Cr Ni stainless steel (18/8), and I find it more difficult to turn or mill than the freecutting 303 grade. If you are going to turn the stainless steel my advice would be 303.

Thor

I agree with that.

[tvoght]

I also agree that 303 is much more machinable than 304. I'll add that I like 416 -another free-machining grade- even better than 303. The 416 is generally only available as round stock. I see onlinemetals has it.

At speedymetals.com I like to look at the characteristics of the various metals, which include "machinability". For steels, they give machinability as a percentage of a reference steel B1112 (which I know little about). In other words, in this comparison B1112 would have a machinability of 100%. For comparison, here are the machinabilities of the three stainless grades discussed here:

304 SS: 45%
303 SS: 78%
416 SS: 110%

And for one more comparison, 12L14 leaded steel has a rating of 193%.

--Tim

[crueby]

I also agree that 303 is much more machinable than 304. I'll add that I like 416 -another free-machining grade- even better than 303. The 416 is generally only available as round stock. I see onlinemetals has it.

At speedymetals.com I like to look at the characteristics of the various metals, which include "machinability". For steels, they give machinability as a percentage of a reference steel B1112 (which I know little about). In other words, in this comparison B1112 would have a machinability of 100%. For comparison, here are the machinabilities of the three stainless grades discussed here:

304 SS: 45%
303 SS: 78%
416 SS: 110%

And for one more comparison, 12L14 leaded steel has a rating of 193%.

--Tim

How does the 416 compare for corrosion resistance? Does it take silver solder well?  If those characteristics are good also, I'll throw some in next time I put in an order and try it. Thanks!

[Kim]

Thank you Thor, Chris and Tim for the quick advice!

I'll stick with 303 - or maybe the the 416.  But, as Chris said, I'd need to make sure it takes Silver Solder well too.

The reference to Speedy Metals is great too!  I've ordered from them, and seen their % machinability, but didn't even think to look at it here!  That's a great idea.

Thanks,
Kim