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Gator
03-14-2012, 02:04 PM
Hi All,

Dunno where does this belong, so mods pls move to wherever it should be.

Anyway, I have a chance to analyze steel compositions using very precise equipment, and the price that is reasonable (100$ per sample). Still rather steep, but a lot better compared to last quote which was 500$.

The catch is that samples go into SEM vacuum chamber, so has to be a small piece. The only thing I have in a suitable size is a very small global knife, I am still curious about CHROMOVA 18 steel, even though it's most likely AUS6.
Anyhow, I know it's a slim chance, but if anyone has pieces of steel few mm will do, from the alloys with unknown makup please contact me..

ajhuff
03-14-2012, 02:35 PM
Why go this route when a spectrometer will suffice at a fraction of the cost?

-AJ

Crothcipt
03-14-2012, 03:44 PM
I would say more precise on what alloys are in the make up.

ajhuff
03-14-2012, 03:56 PM
There's no need for that extreme precision. Next time I am in MI or WI I plan on burning a few of my knives to see what they are. Will have to pick the monosteels of course. I am really curious on the Nenohi though I have heard they are clad. If they are, arc spectroscopy won't work.

-AJ

Gator
03-14-2012, 04:02 PM
Why go this route when a spectrometer will suffice at a fraction of the cost?-AJ
For one, I can not find any lab in bay area which will do analysis on the knives at less than 500$.
Two, I don't know how accurate the spectrometer will be. Week ago I got contacted by gentleman from UK who managed to analyze Mac Tungsten SS on spectrometer, it couldn't pick up any Tungsten in it, and I don't know the details but apparently the device was not set up to to detect Carbon at all...
Anyhow, if someone knows a reliable lab in bay area, I am very open to suggestions :) I am reluctant about sending one of a kind knives back and forth to unknown testers, which is why I want local source...

ajhuff
03-14-2012, 04:23 PM
We tend to do combustion for C and S as it is more accurate but spectrometer isn't too bad. True, you have to use a lab that analyzes steel to make sure they have the right channels on their spectro. But you don't need extreme precision. If your C measures 0.95 instead of 0.97, it's essentially the same thing. And measuring 0.9568 means nothing. Same as 0.95. Reach out to a local steel mill or steel foundry. They might be willing to help.

-AJ

tk59
03-14-2012, 04:27 PM
Do you have a list of such steels? What is the minimum sample size?

TB_London
03-14-2012, 04:47 PM
Carbonext would be interesting to know, as would Shigefusa's swedish

Gator
03-14-2012, 05:15 PM
0.95 instead of 0.97, it's essentially the same thing. And measuring 0.9568 means nothing. Same as 0.95. Reach out to a local steel mill or steel foundry. They might be willing to help.

Well, for Carbon that's true, for S and P it's better to have at least 3 digit precision, since the specs are that precise and "clean" alloys are valued based on that. As for the local mills, that's what I did 2 years ago, calledpretty much everyone around... You'd think in hi tech place like bay area it shouldn't be a problem, but apparently prices are also very bay area-ish... 500$ per sample was the best offer. until I found 100$.


Do you have a list of such steels? What is the minimum sample size?
Not sure if you're asking me :) Any steel for which I don't have a data in the knife steel composition database (http://zknives.com/knives/steels/steelchart.php) will do. I have 3 that I want to evaluate, if I can, Global's CHROMOVA 18, Shigefusa Swedish and Mac SS Tungsten. I already have Aritsugu gokinko and TKS Special steel compositions, so those two are off the list. Carbonext is another one that comes to mind. And Kobayashi uses another mystery "cobalt stainless"... Sample sizes I was told few mm would suffice, considering it's SEM, I figure even 2mm piece will do.

jmforge
03-14-2012, 05:28 PM
You could always trim a bit off of the tang of a wa blade or punch a little piece from the tang of a western style knife.:bigeek::biggrin:

ajhuff
03-14-2012, 05:34 PM
Yeah I get that. My spectrometers all read three decimal on P and S. But there is virtually no significant difference between 0.005, 0.0055, and 0.00555 S. Your lower threshold is important. I don't. Think mine were set up to read below 0.003% S. Or for example I couldn't read Pb below 0.001 but it didn't matter.

Where is the Bay Area. For me that is Green Bay. :D. San Francisco? I used to do some work at CERP. Which is a quasi government facility on the old McClellan air force base. That's. San Fran right? They changed their name buy they might be able to help you.

-AJ

ajhuff
03-14-2012, 08:15 PM
Do you know what you'll be getting for $100 SEM? Make sure you know up front what analysis spectrum will be. A typical ferrous test will have:
C
Si
P
S
Mn
Cu
Cr
Mg
Mo
V
Ti
Al
Pb

You will want to add tungsten of course. I would suggest Boron for sure. And maybe Antimony and Tin. I would question whether or not you are getting all of those. Also remember that with SEM you are getting more specific in your testing area, not as bulk averaging as in OE Spectrometer. That's great if you want to know the chemistry of a carbide, not so much the steel as a whole.

Most quotes require a phone call at least but these guys have a price list on line. I know nothing of them other than that. Spectrometer testing is $60.

http://metalstesting.com/media/Price_Schedule_2012.pdf

-AJ

ajhuff
03-14-2012, 08:59 PM
I should point out the negative downsides doing a test like arc spectrometer. You need a flat surface that can cover about a 3/8" diameter hole and seal it. Tested surface are usually ground to a 60-80 grit finish. There will be a burn mark where the testing was done. Visualize the equivalent of a cigarette burn on steel. Doubtful that you could completely polish it out. Typically there would be 2-3 closely spaced burns and then you take the average for the results.

-AJ

Gator
03-14-2012, 11:27 PM
Well, as I understand it's focusing XRAY on the metal and then analyzing reflected beam. Should be very accurate and non destructive. The downside being the size of the SEM chamber.
Thanks for the link. I've talked to them before, didn't work out. Shipping the knife and explaining where to test, they were worried about breaking the knife etc, made me worried too...

jmforge
03-14-2012, 11:36 PM
Just out of curiosity, are you looking to do this just to know or to try and reproduce some of these steel types or find ones that are most similar from other manufacturers?

Andrew H
03-14-2012, 11:44 PM
Just out of curiosity, are you looking to do this just to know or to try and reproduce some of these steel types or find ones that are most similar from other manufacturers?

It sounds to me like Gator is trying to find out what the composition is of some 'unknown' steels. Shigefusa, CarboNext, etc.

JohnnyChance
03-15-2012, 12:05 AM
Just out of curiosity, are you looking to do this just to know or to try and reproduce some of these steel types or find ones that are most similar from other manufacturers?

You should visit his site (http://www.zknives.com/knives/steels/index.shtml), might give you an idea of his intentions.

jmforge
03-15-2012, 12:08 AM
YEs, i had seen that before. Os just for fun, eh? Cool.
You should visit his site (http://www.zknives.com/knives/steels/index.shtml), might give you an idea of his intentions.

James
03-15-2012, 12:42 AM
Well, as I understand it's focusing XRAY on the metal and then analyzing reflected beam. Should be very accurate and non destructive. The downside being the size of the SEM chamber.
Thanks for the link. I've talked to them before, didn't work out. Shipping the knife and explaining where to test, they were worried about breaking the knife etc, made me worried too...

yep; basically you energize the particles and they emit electrons with energies characteristic of the element they came from (photoelectric effect). As ajhuff mentioned, there will be burn spots, but in my experience, these are extremely small and perhaps not even visible to the naked eye, or at least they were when I was using SEM EDX on various teeth.

Gator
03-15-2012, 02:19 AM
james - Yep, SEM EDAX, and as I understand very accurate. Problem for now is getting teeth sized samples :) I certainly do not with that to anyone, but if someone has broken tip or whatever part, or may be someone modded the knife andhas pieces left... Long shot, but better to ask than not to.
*******, I guess you already have your answer, steel chart is my "knife community service", and to be honest I am really curious(about all things) too.

Oh, and if someone has a good idea on how to remove small amount of metal from the knife w/o seriously damaging it, and keep removed pieces clean (i.e. if I just collect particles after sharpening, it'll be mixed with stone particles, so I figure not good for testing)...

SpikeC
03-15-2012, 02:10 PM
I have some files that are RC71. They should be able to get some filings from just about any knife made, would those be enough to do the job?

EdipisReks
03-15-2012, 03:56 PM
if I just collect particles after sharpening, it'll be mixed with stone particles, so I figure not good for testing

that's what magnets are for.

Andrew H
03-15-2012, 04:15 PM
that's what magnets are for.

As long as you use don't use multiple steels on one stone this should work.

ajhuff
03-15-2012, 04:22 PM
You need to make sure with the lab. Way back when when I made SEM samples they had to be mounted and polished. You needed a sample about 5mm square. Might have been a different technique though.

-AJ

Gator
03-15-2012, 04:41 PM
Yeah, checking on the sample size.
71HRC file sounds interesting. Spike, where can I buy one of those?
Magnets would probably work too, that was the first solution that I had, but I'm sortta skeptical, fine dust from the stone might get picked up along with the metal and affect the result...

EdipisReks
03-15-2012, 06:19 PM
Yeah, checking on the sample size.
71HRC file sounds interesting. Spike, where can I buy one of those?
Magnets would probably work too, that was the first solution that I had, but I'm sortta skeptical, fine dust from the stone might get picked up along with the metal and affect the result...

poor the slurry into a (thin plastic, preferably) bowl of distilled water, agitate it a bit, put a strong magnet on the bottom of the bowl, and then pour off. repeat a couple times.

SpikeC
03-15-2012, 06:26 PM
Te files that I'm talking about come from Grobet, the Valorian line. I get them from Stuller, but you have to have an account with to buy.
And they are sort of expensive!

Gator
03-15-2012, 07:27 PM
I feel like an alchemist already ;) But if all else fails, why not. Knowledge is power!
Spike, what is "sort of expensive" if not a secret? I don't need a big one, small will suffice.

SpikeC
03-15-2012, 07:43 PM
A half round slim ring file, 8" overall is just over 38 bucks. They do last a long tome, though!

andoniminev
06-05-2012, 03:06 PM
damn, I had a little chip from my Shigefusa. I should have saved it. Should I chip it on purpose, I am dead curious :viking:

tk59
06-05-2012, 03:12 PM
I'd send him a pm. I'm sure he has a number of samples to test out. I'm pretty curious as to how the first few samples worked out, myself. :)

bieniek
06-05-2012, 04:03 PM
Shigefusa Swedish and Mac SS Tungsten. .

These, yes please. The MAC is really interesting. Not really SS though...?

ajhuff
06-05-2012, 04:13 PM
These, yes please. The MAC is really interesting. Not really SS though...?

In what way is it not stainless steel? Chrome is too low?

-AJ

bieniek
06-05-2012, 04:59 PM
Dont know what makes it, but it rusts pretty fast. I once left it for couple of minutes on the stone wet and there it was, nice and orange.

ncowan
06-10-2012, 06:57 AM
let me know if you have tested them or not. My neighbor happens to work for thermo-scientific and he sells the $65,000 analyzers from home. He tests my steel for free. I'd be happy to test your samples for you.

ajhuff
06-10-2012, 09:33 AM
let me know if you have tested them or not. My neighbor happens to work for thermo-scientific and he sells the $65,000 analyzers from home. He tests my steel for free. I'd be happy to test your samples for you.

ARL OES. Not my favorite brand but that's what I'm talking about instead of SEM.

-AJ

ncowan
06-11-2012, 05:17 AM
ARL OES. Not my favorite brand but that's what I'm talking about instead of SEM.

-AJ

His analyzes won't test for carbon. But based on the chemistry or the steel it wirelessly accesses a database and tells you the name of the steel and you cam see the carbon content that way. I guess it wouldn't do much good for testing proprietary steel samples. Although I bought a knife with a proprietary steel saying high carbon with moly. And it was just 440a with extra carbon added to it. The analyzer read it as 440a but it still rusts fairly quick. Good luck with your tests man, the offers on the table if you ever need it.

ncowan
06-11-2012, 05:18 AM
I mean to say oxidizes fairly quick.

Gator
06-12-2012, 01:27 PM
I have a file(Thanks SpikeC), prepared sample for Global Chromova18 steel, which I hope is a good enough sample for testing. Waiting on the other guy to respond, when he can do the test. If this one goes ok, I'll file off some Shige and Mac.
Ncowan, if I don't hear from tester for a while I'll definitely check with you on testing samples. Thanks in advance.

Gator
06-13-2012, 10:18 AM
Update - First sample went out this morning. Fingers crossed :) I certainly hope mutilated edge on that Global paring knife will not be in vain.

andoniminev
06-13-2012, 01:13 PM
Update - First sample went out this morning. Fingers crossed :) I certainly hope mutilated edge on that Global paring knife will not be in vain.
:doublethumbsup:

Crothcipt
06-13-2012, 05:21 PM
Can't wait. They have me wondering myself.

andoniminev
08-14-2012, 08:55 AM
any updates?

Gator
08-22-2012, 11:30 AM
Alas.. Sample sent, periodically asking. Last I've heard was month ago - "plan ot have session on SEM next Friday", noting since then. I'll send another email today.