What kinds of steel are non-magnetic?

[JTknives]

That what I thought I read somewhere. I also thought that the nickel content made it stainless, or at least closer to stainless.

stainless property's come from chromium not nickel i believe. not saying that nickle does not help but i order for a steel to be considered a stainless it has to have something like 13% chromium content.

 

[go mike]

stainless property's come from chromium not nickel i believe. not saying that nickle does not help but i order for a steel to be considered a stainless it has to have something like 13% chromium content.

I see. I always thought nickel helped in stainless, but I could have been wrong. (Although it would be the first time I was)

stainless steel 
–noun
alloy steel containing 12 percent or more chromium, so as to be resistant to rust and attack from various chemicals.

 

[sulsaMatt]

I never tried to forge any of it. Never had any reason to but it may be hot short. Any kind of milling, drilling, or lathe work is what I was referring to and it isn't from the heat. Grab a hacksaw and jump on a piece of 316 if you want to see a blade get dull real quick. Same thing with any cutting tool made of tool steel.

I actually was talking about machining too, using a decent amount of coolant and low RPMs. Thanks to Mete, I'll up my feed. I recently got a HF mill lathe combo at a yard sale, this might be a good time to practice. On the topic, can you solder stainless (esp. 300 series) to 1095? I have some stay bright, will that work?

 

[pocketfulladoubles]

Depends on what you mean by non-magnetic. 304 is basically non-magnetic, but can become slightly magnetic (I mean really slightly) if you drill into it or work it. 316 would probably do the same. This is really only going to be an issue if you are intending to manufacture something that will be in the presence of large magnets.

If you need something TRULY non-magnetic (permeability = 1.0001), I would look toward Inconel 686 or Haynes 25. Nitronic 50 is probably next on the list. These steels do not change magnetic properties after working on them.

 

[Steve Hayden]

Depends on what you mean by non-magnetic. 304 is basically non-magnetic, but can become slightly magnetic (I mean really slightly) if you drill into it or work it. 316 would probably do the same. This is really only going to be an issue if you are intending to manufacture something that will be in the presence of large magnets.

If you need something TRULY non-magnetic (permeability = 1.0001), I would look toward Inconel 686 or Haynes 25. Nitronic 50 is probably next on the list. These steels do not change magnetic properties after working on them.

Welcome to Knifrmakers Forum. This is the place for the serious Knife nut and steel fanatic .

 

[mete]

Staybright solder works fine for both stainless and nonstainless. For stainless make sure you use a flux designed for stainless.

 

[C L Wilkins]

My brother-in-law found a huge piece of stainless flat bar 22x2x.25. Looks like someone tried to grind in a machete blade. Pretty crude. The steel was found in the middle of the desert and had no surface rust. I assumed it was stainless and tried cold blueing a fresh ground spot. I got zero result. I then ran a neodymium magnet, and got zero magnetism. I don't like to use totally unknown steel but I could cut it up and use it for guards or something. Do the aforementioned tests indicate what type of steel this might be? It definitely isn't aluminum or titanium. Any help is appreciated!

Rule of thumb...

Any non-magnetic steel is a non-hardening steel which makes it a non-knife blade steel.

Note: the cobalt based knife blade materials, such as talonite or stellite are serviceable knife blade material but will not harden. They make a great, yet expensive, dive knife. Addtionally, Tom Mayo makes a great TNT!

Craig

 

[sulsaMatt]

Staybright solder works fine for both stainless and nonstainless. For stainless make sure you use a flux designed for stainless.

Thanks Mete. Sounds like I have a pretty good inventory of ss cross guards. I typically do cord wrap handles and .250" is nice and beefy for that style.

Rule of thumb...

Any non-magnetic steel is a non-hardening steel which makes it a non-knife blade steel.

Note: the cobalt based knife blade materials, such as talonite or stellite are serviceable knife blade material but will not harden. They make a great, yet expensive, dive knife. Addtionally, Tom Mayo makes a great TNT!

Craig

Thanks for the heads up, but I hadn't really intended on using this for blades, I was just wondering how many cutters I was going to go thru.. or if I should just go with brass.

 

[pocketfulladoubles]

You'll be fine with stainless. It takes some practice, and the cutters cost more. If you really want to cut it and get the best life out of it, use a high-performance solid carbide bit with a Titanium Nitride coating, and an extra thick cutting fluid. It is sensitive to vibration, so you need to have a good mill and vice really locked down, and watch the RPM's and heat closely. It's been too long since I've worked on much stainless, but the tip angle for drills and the flutes on end mills will also affect it, but your local machine shop supply should be able to help you with that. 316 is a very good all around stainless in terms of corrosion resistance. My comments about the super-alloys above, in regard to magnetism, is only it you are making medical grade equipment that will need to be around something like an MRI or research equipment (and even then...).

 

[P.Brewster]

Don't think that you MUST use carbide. We drill, tap, and counter-sink 304 and 316 everyday at my work with El Cheapo tooling. Just learn how to sharpen.

 

[go mike]

Speaking of el cheapo tooling, HF has some really good quality drill bits. (Or maybe I got a good batch) but I've got their pack of 1/8" drill bits, and I'm on my first bit from it, and I've drilled over 50 holes and it is still as sharp as it started. And, I have about 9 more after that one finally dies. No lube or not much anyway on them either.

 

[pocketfulladoubles]

Don't think that you MUST use carbide. We drill, tap, and counter-sink 304 and 316 everyday at my work with El Cheapo tooling. Just learn how to sharpen.

True, if you have the ability to resharpen and know what you are doing because you do it day after day. I've just had bad experience with breaking and wearing out bits, so I just moved to the coated carbides to avoid the hassle. The extra cost for me was worth the headache savings. And, they last a long time if you treat them well even on 316.