440c versus ats 34

HELLGAP

HELLGAP

Dealer - Purveyor
I got into a bit of a dissagreement with a maker today at a show today. He was trying to tell me that 440c has better edge retention than ats34. I dissagree, i have 2 pieces but never used it but have used its american version 154cm a fair amount. I find it very very hard to believe that 440c even on its best day is a better steel tha cruciables 154cm .I know they make 440c as well as do other steel mills . But from all the books and charts 440c is about 2 steps below 154cm or ats34. I went to the Engnath site to look and cant find where the comparisons were done. Im thinking that ats 34 out cut the 440c by about 35 % in the over all testing please some correct me if im wrong. Do most makers use 440c because its cheaper and grindes easier and thus makes knives faster.You would think they would want a superior steel if they are spending all that time making a knife. Kellyw
 
I bought some 440 c just becuase it was cheap but ats 34 is just a few dollars more probably what i will get next time
 
Ive never used 440c so I cant speak to its performance. I have used alot of ATS34, and I really like it, holds a good edge.
 
Why not do a comparison test on rope-cutting? The test does not take too long to do, and can be done on a soft wooden board which I've found does not dull the edge. Make sure they are the same hardness so that you are comparing apples to apples though.
 
Having used both, and tested them for edge-holding in similar knives, ATS-34 seems to be about 10% jbetter in that department. 440C does have better corrosion resistance, but ATS-34 isn't lagging too far behind. 440C takes a better looking finish than ATS-34 and is easier to finish. I can't tell much difference between the two as far as grinding goes. If you shop around, there isn't much difference in price, either.
 
Todd Robbins said:
Having used both, and tested them for edge-holding in similar knives, ATS-34 seems to be about 10% jbetter in that department. 440C does have better corrosion resistance, but ATS-34 isn't lagging too far behind. 440C takes a better looking finish than ATS-34 and is easier to finish. I can't tell much difference between the two as far as grinding goes. If you shop around, there isn't much difference in price, either.
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That's pretty much the same thing I've observed and read about the comparison. I've used them both quite a bit but one thing I learned from talking to some people '"in the know" is that ATS 34/154CM is tougher at higher hardness's, I've heard that 440C is more prone to edge chipping due to the higher chromium content.

BTW, I'm a little worried that this thread could be a little controversial, as you found out at that show, people have strong feelings about this subject..... so as an admin I'd like to try to preempt trouble and remind everyone who is thinking about replying to please keep it civil and don't take this personally :)
 
What I do know is not all 440C is created equal

My personal user knives are 440C. Depending on where the 440C comes from is a world of difference. The most positive thing I can say about ATS 34 is it's more consistent. I have used and tested enough that I can mirror polish a 440C blade and tell by looking at the grain structure where I the steel likely came from and how it's going to hold an edge.

Right now I can't get any more 440C from my normal supplier and he doesn't know when he will get another batch made. When I found out how nice the last batch was I bought a bunch a few years ago but that supply is down to enough for just a few knives depending on their size so it's being saved for myself and certain customers that want knives from it. That's why I've been using more ATS 34 than in the past when the CPM dried up for a while.

I am finishing up some knives now with that 440C but those are ones that I've had heat treated laying around for three or four years and never got time to finish. I hadn't used it for about six months and had almost forgot how clean that steel was. One of them is the "Safari" knife I posted in the gallery. The mirror polish picture in the gallery is one from it also. That steel is so clean and consistent you can't see any grain in it much like the CPM154 when you happen to get a clean piece of it.

I'm finally getting around to cutting some knives from Carpenters CTS-XHP with high hopes of it being the cats meow. The few makers I've talked to that have used it are saying it is. It's a powdered metal version kind of a cross between 440C and D2. Basically a higher carbon 440C in a powder metal.
 
I am by no means trying to wack a hornetts nest. I know 440c buffs up easier and there fore may be a cleaner steel. I am using ats 34 because alot of canadian makers dont use 154cm because of the cost of shipping to canada. I really dont like the way its so darn hard to grind so darn hard to polish , but hmmmmm just darn hard. All the knives out of 154cm have been RC at 59.5 to 61 . I will say its no fun hand sanding either. I hope the price drops down to a better price than its last offer up in Canada to the whole sellers or debating its edge retention will be history. Does anyone know the web site for hands on testing by the master s Kellyw
 
I just started using s.s and studied 440 c and ats-34.
From all I had read there wasn't much difference. 440 c is supposed to finish better but ats-34 is supposed to take and hold a better edge.
The reason I chose ats -34 is I had also read people associate 440 with junk knives because Of all the Pakistan knives stamping 440 on their knives even though it wasn't 440 c.
 
I started out using 440C about 20 years ago and have stuck with it because it meets my requirements...(1) Hold an edge long enough to dress, skin, and quarter a moose without sharpening...In fact some hunters tell about doing two moose without sharpening, just can't shave with it anymore.

(2) Resistance to edge chipping...we have had people cut off 3/8" steel bolts without damaging the cutting edge of the moose knife..the spin had several dents from the hammer being used to drive the edge through the bolt.

(3) Flexibility to resist breakage...enough said

(4) Good finish .

Why would I change material when the steel I started with has handled everything that I have handed to it for all those years?

George
 
I used a lot of 440c over the years, and was fine with it for the most part. Then I had some that looked terrible. About that time, early 90s, I went to ATS34 because it was supposed to hold an edge better (as was its parent steel, 154cm) and it was supposed to be very clean, much more so that 154 and 440c. So I used ATS for years. Then I had a bunch of it that looked terrible. I went to 154 until. . . It seems that a lot of it was not so well made, having "cloudy" stuff in it. It wasn't too big a problem for me because I used a lot more damascus than stainless. I discussed this with a couple of guys, including Bailey Bradshaw. Bailey believe that there was so much chromium in the alloy that it didn't completely go into solution and left those brighter cloudy or ghosted areas. ATS started out great, but I've heard from several other makers that it has gotten dirty over the years. It's about the same price as 154cm, so I chose to use an American made steel over a foreign made one. These days I use CPM154 when I want a stainless blade. It's more expensive than these others, but it's worth it. It's performance and the finish I get (hand finish only; no mirror buffing) are superior.

All of these steels will make a good knife if they are properly heat treated and properly ground. However, in a well controlled cutting test a blade made from 440c will not perform as well as ATS or 154, and they won't perform as well as CPM154. Like any stainless blade steel, they all will rust under the right conditions and they won't take as much punishment at many carbon steels.

The "junk knives" from Pakistan and elsewhere that were made from 440 steel most likely had 440A blades, not 440C. Big difference in the two alloys.

HELLGAP, I do most if not all of my grinding after heat treat. I find that any of these steels we're talking about grind easily with the higher performance abrasives, and hand finishing has been no problem with silicon carbide paper. Now those alloys with a "V" at the end are very different!

I will be giving some AEB-L a try shortly. Fine grain, higher hardness than 440c, supposed to be easy to grind and finish, and it's less expensive.

cotdt, in a cutting test you want to have each steel at its optimal hardness. That isn't always the same. For instance, 440c is maxed out at around 60Rc and is usually tempered down to 58-59, but 154cm gets harder and works well at a higher hardness, which is the way it's supposed to be done.

And for what it's worth, the only blade I've made that broke was one made from 440c heat treated by Paul Bos.

David
 
I'd rather have a properly treated 440-C than a marginally treated ATS-134. Just because it is technically better doesn't mean any particular maker has the ability to maximize the characteristics of every steel- including myself. Who is the perfect maker with all steels....? Cheverolet may make a better racecar than Ford, but that dont matter if the Ford has a better driver.
 
DLBrothers said:
I'd rather have a properly treated 440-C than a marginally treated ATS-134. Just because it is technically better doesn't mean any particular maker has the ability to maximize the characteristics of every steel- including myself. Who is the perfect maker with all steels....? Cheverolet may make a better racecar than Ford, but that dont matter if the Ford has a better driver.
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Your first statement about the steels is true, Dennis. If the geometry of the blade is good, then a proper heat treatment will make the difference. However, it really isn't hard to maximize the characteristics from the given steels. Heat treatment is very important and the numbers need to be followed, but it's easy enough to do, whether at a professional heat treating service or in your shop with a good oven. The heat treatment of all these steels being discussed is pretty much the same with the slight differences being in the temperature and soak times.

As for the race cars, back in the day my Buick GS400 ragtop would waste most comparable Chevies and Fords, whether their drivers were good or bad!

David
 
I agree with your point Dave. Perhaps it would have been better said this way: The best steel is whichever one that best fits the intended use and that the maker is best skilled at using. Even with all the data, it takes practice- I'm referring to sole authorship here. But even HT contractors claim they are better than the competition. If there wasn't possibility of variance, they couldn't make that claim.
 
George , David thank you both for the detail and explanation. I know that the differences in quality from 440c to ats34 or 154cm is small . And George I completely agree with you and some 440c steels are better pending what plant they come from.If they have worked well why change. The heat treat can make a big difference in overall performance as well . The steel I use the most is cpm154 for any big blade skinner and so on and 154cm for all filleting knives. I may switch on the fillet knives just to see if I notice a differnce while finishing. I tend to think if its hard to grind /sand / finish , then the edge retention should follow suit
 
Cliff Fendley said:
Depending on where the 440C comes from is a world of difference.
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I'm learning this the hard way. I have a bar of 440C (won't mention where I got it, except to say it's not from a dealer or member here) that I bought just to check out this well-known alloy. Unfortunately, it seems like it came from not-the-best mill or something.

It drills and grinds just fine, but as soon as I get a halfway decent grind on it, I can see weird marks in the steel. Can't get a decent picture of it, but it reminds me of the "floaters" you see in your eye when you look at the sky or a snowbank, little wiggly marks all over that only show up at a certain angle. It's an irregular pattern all throughout the entire 36" bar. It shows up at a rough 50-grit grind and only gets more noticable the finer I go. It's downright fugly.

Anyone ever seen this? Will it go away after HT? Part of the reason I wanted to try 440C was for the fine finish it's known for, but obviously the knives from this bar won't look good that way. I suspect I'll have to give them a very basic machine finish and that burns me up because I'm trying to learn how/establish a reputation for a nice clean hand-rubbed polish.

Frankly I'm not amused at all because it remains to be seen if I'll even have enough confidence to sell these knives. To me, it's a pretty expensive learning experience when I add up the steel, belts, labor and HT costs. I have a couple hundred dollars tied up in ugly knives I'm not sure I can sell! :what!: To make it even more fun, I have two very large and expensive 440C blades (from a different supplier) for a custom order being cut by waterjet as we speak... more money and time invested. Luckily the looks of the steel won't matter as much for these two because the client wants them oxide-coated anyway. But it still makes me leery.

I've never seen this on CPM-154, O1, 1080, 1084, CPM-3V or D2, and I've ground and finished many, many feet of these alloys. I'm not biased against 440C; I've seen many beautiful and durable knives made from it. But I won't be ordering any more, especially not from that supplier. :mad:
When it comes to SS I'll stick with CPM-154.
 
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James, the "floaters" description is a good one, except the floaters I've seen in the steel are huge. I've seen it in one piece of 440c 20 years ago. I haven't used much 440c in more recent years so I don't know how much of a problem it is. I have seen it a couple of times in 154cm. I believe the most "floater" problem I've observed was in ATS34. More blades, and those defects were huge. I have not seen the problem in CPM154 or any other stainless or near stainless steels.

I found that the finer the finish the more they showed up. I don't mirror polish my blades, but the finer the grit of sandpaper I used the more you could see those defects as a tone on tone "ghosted" pattern. All of my blades were finished after heat treatment.

I discussed this with Bailey Bradshaw once. Bailey has a fair amount of knowledge about metallurgy. His best guess was that because there was so much chromium in these alloys that not all of it went into solution and sort of clumped together.

As for the source of the particular pieces that had the defects, I always bought my steel from a reputable source, usually the same one each time. The ATS was made by Hitachi Metals in Japan and imported into the US. Whether the 440c and 154cm came from Crucible or was some imported clone I don't know.

It is pretty frustrating to build a nice knife and have the finish of the steel to down the tubes just as you're about done!

David
 
David Broadwell said:
... I don't mirror polish my blades, but the finer the grit of sandpaper I used the more you could see those defects as a tone on tone "ghosted" pattern...
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Exactly. These aren't even HT'ed yet let alone finished, and I can see it; I doubt it will get any better. These "floaters" are quite small, but they're EVERYWHERE, I mean in every square centimeter for goodness sake. Oh well, I guess they'll be beaters. :( Seems a shame to put a coarse finish on a good stainless blade... it also makes me worry about the durability/consistency of the edge.

The "clumping" chromium theory makes sense I guess. Perhaps the particle process is partly why I haven't seen it in CPM-154, even though it also has a lot of chromium. Did I mention the more I work with CPM-154, the more I REALLY like it? :)

Wait... think I could charge extra for the floating ghost pattern?!? :biggrin:

P.S. yeah I know I'm being kind of anal about this... but if I wasn't anal I'd just stamp blades out of 420 and call it good ;)
 
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