Forging stainless steel

[Sam Falzone]

Greetings all,
I've been thinking about experimenting with some stainless steel - some friends have asked me to make them a place setting of forks and possibly spoons as well. I've made forks from mild steel but I would like to try making them from stainless steel, but I've never forged stainless steel before. I would appreciate any warnings, wisdom or advice about working stainless steel. :D

[Dave Leppo]

I asked about stainless on the GURU'S DEN @ ANVILFIRE.COM. I was forging 300 series stainless items for the bathroom and they were rusting. "Quenchcrack's" response - Friday, 08/22/08 19:10:39 EDT

- Glenn, if this is a policy violation I urge you to delete this post

This does NOT violate IForgeIron policy but is in direct violation of Anvilfire policy. Anvilfire policy is that NO AMNONT of text can be copied from the Anvilfire site, no matter how small, without permission from the Anvilfire. The responce has been reworded to pass along the information without violating the Anvilfire policy.

The stainless steel 300 series is high in nickel and chromium. 300 series with an L is for low carbon and you most likely, by getting it hot enough to form chromium carbides, depleted the chromium. The surface formation of chromium oxide is used to protect it from additional oxidation, which will not be cured by surface passivization. The carbides must be dissolved to release the chromium. Heating to 1800F-2000F and water quench will release them, and dissolve the chromium barbides which will prevent their re=precipitation. Use the L version in the future, as it does not require the additional heat treatment.

This I did with later items – heating to bright red-orange and quenching. Cant tell you if this worked or not – OK so far.

[Gary]

I brought this up last year, there's a link to the posting below, or search "working stainless steel". I followed advice given on using 304 SS, worked it like steel and had no problems. I made several gaff hooks, I'm told they have not rusted yet. Hope this helps!


http://www.iforgeiron.com/forum/f7/working-stainless-4308/

[jeremy k]

I have been forging Stainless for most of the day today 304 - sizes from 1 inch round to 1/2 inch round. They are some tapered parts for a branch type theme on a set of fireplace doors. The heat does dissipate very quickly and does forge a bit harder than mild steel but very doable. JK

[Hillbillysmith]

They are right that you want a low carbon type stainless steel to forge with. But the reason that it will rust is that the chromium atoms combines with the carbon atoms to create chromium carbide. The process is called carbide precipitation. I do not know if re-heat treating the stainless will keep it from rusting or not, I would say definitely no, but I haven't tried it. I have, however, forged stainless before and like Jeremy K said, the heat dissipates very quickly and it is harder to forge.

Good luck
-Hillbilly

[devon blacksmith]

Hi I forge 316 stainless and find that if i buff up the work after it does not rust ,I have been told that using a steel hammer I am leaving steel on the top surface of the stainless,uther than that I find it about the same to forge as a high carbon steel.

[chyancarrek]

Hey Sam,

For my work, it's trial and error - I'm using only reclaimed materials so I never know the exact alloy of the SS..

What's been posted above is good advice - especially that SS will make you earn every bit of progress.

All of my SS work so far has been forged at low to high orange then goes into a Muriatic bath for 24 hrs, gets scrubbed, then sanded using finer grits in stages then buffed. My stuff is usually used as serving dishes so it sees a lot of moisture and so far, using this method has kept my work rust free.

I've attached a couple of pics of a bowl I made from a SS shelf from a computer component rack.

The current owner uses it for everything from salads to mashed potatoes and it hasn't rusted up.

[larrynjr]

this is a very timely topic! I hadn't gotten around to searching the archives for SS topics but am starting to consider what to make people for Christmas presents and was thinking meat flippers / forks out of SS.

Great minds think!

[larrynjr]

So I just was browsing the archives regarding working with SS and it sounds like it's barely worth the effort. So if I make meat flippers and forks with mild steel what is the best way to keep them from rusting? Vegie oil after use / cleaning?

[Frosty]

Passivate SS with nitric acid after you're done working on it and it's stainless again.

Frosty

[chyancarrek]

Hey Larry,

Yeah, Just cook it on - I paint mine on with a cloth @ about 600 - 800 degrees and just keep wiping it until it won't take anymore.

Tell whoever gets it to maintain it by wiping it clean and keeping a fresh coat of oil on it after use.

If it does rust up a bit - 000 steel-wool dipped in vegetable oil cleans it right up.

[archiphile]

When you use steel tools with stainless, you are imparting FE on the surface of the SS. This surface inclusion will cause the SS to have rust spots. When I was welding Hi-purity SS High pressure pipe and High Level Nuclear waste containment systems we had to completely enclose ourselves in special rooms to mitigate the FE inclusions.

When you heat SS you are also releasing [Hexivalent Chromium](Safety and Health Topics: Hexavalent Chromium) which is carcinogenic .

[divermike]

My buddy Bob Trout told me it takes 33% more enrgy to work with SS, I have found it to be at least that much harder to work, any thoughts?

[Frosty]

My buddy Bob Trout told me it takes 33% more enrgy to work with SS, I have found it to be at least that much harder to work, any thoughts?

I don't know any numbers but it is most certainly harder to work. It has more resistance to movement at heat. It is a poorer conductor of heat so must spend more time in the fire to come to temp. It has a much narrower working heat range which means it spends even more time in the fire for the time working it.

Not to mention saw blade, grinding wheel, sander, etc. wear.

So. . . Yeah, more energy to work, all round.

Frosty