...so what lock-arm metal is used for laminated ZDP blades

[Metalbuff]

I am curious, on my caly3, what the mating metal is made of on the locking arm. It seems that every thread Ive searched about lock-bar/arm material, I can never get a straight answer about if they are made of the same steel as the blade. Every response to someones question about it is basically "pretty sure they are the same metal"...or..."I bet they are the same metal". Has spyderco or anyone with credibility on this matter confirmed this question?

I am especially stumped on the laminated steel models. My lock-arm on my caly3 is definatley not laminated. So what steel is it?

[yablanowitz]

I don't know what steel it is, but Sal posted in the past that they use a different steel for the lock than they use for the blade in order to prevent galling. I also gather from various posts that he has some pretty strict heat-treatment requirements for the lockbars as well as the blades.

[The Mastiff]

I'm pretty sure that type of information is confidential. Not many companies do give out that kind of stuff. Joe

[Metalbuff]

I'm pretty sure that type of information is confidential. Not many companies do give out that kind of stuff. Joe

It's just a simple part of the knife setup, which is not that difficult to find out for yourself if you are a knife maker/forger. To say it is confidential seems a little extreme. If it is even a pressing question for the competition, then the competition has a 50/50 chance of getting it right. The lockbars either are, or aren't made of the same steel as the blade.

Now the heat-treating and various methods used to achieve a certain spyderco quality are most definatley confidential, and they shouldn't "throw" that information out there.

[gaj999]

The lockbars either are, or aren't made of the same steel as the blade.

Now the heat-treating and various methods used to achieve a certain spyderco quality are most definatley confidential, and they shouldn't "throw" that information out there.

On linerlocks, I'd be very surprised if the lock bars are the same steel, for two reasons: The lock bar needs to flex while the blade needs to be hard. Fancy steels cost more, so why pay the extra for a part that doesn't need special qualities? Besides, if all lock bars are the same, they can be heat-treated in large batches across multiple lines if the ht requirements are looser than for blades.

If we're talking lockbacks, the first reason doesn't apply, but I'd expect the ht requirements for the part would be less exacting, so I'd give the second more weight.

Gordon

[yablanowitz]

I guess I'll say it again. The lockbars are NOT made of the same steel as the blades. Spyderco uses a different steel for the two parts in order to prevent galling. At least, that is what Sal told us, and I'm fairly sure he would know.

[THG]

I guess I'll say it again. The lockbars are NOT made of the same steel as the blades. Spyderco uses a different steel for the two parts in order to prevent galling. At least, that is what Sal told us, and I'm fairly sure he would know.

That's what I thought, but then why do people always say when swapping ZDP and VG-10 blades on Delicas or Enduras that the lock bars must also be swapped?

[yablanowitz]

Because the lockbars are fitted specifically to the original blade. Not keeping the lockbar with the blade it was fitted to can cause lockup problems - insufficient contact area, mismatched angles, insufficient seating depth, excessive play, etc.

[SimpleIsGood229]

I'd guess, also, that a ZDP blade would require a lockbar with a higher hardness than that of, say, a VG-10 blade.

[The Deacon]

I'd guess, also, that a ZDP blade would require a lockbar with a higher hardness than that of, say, a VG-10 blade.

That may, or may not, be true. But either way the advice to keep lockbars and blades together as sets is generally given to anyone contemplating a blade swap, even between two VG-10 knives with different color FRN handles. The primary reason for that advice is to maintain the fit.

As for "what metal", and the reason for Spyderco's reluctance to name it, perhaps it's just to avoid the inevitable second guessing by self proclaimed steel gurus as to why the choice is wrong and Steel X would be infinitely superior. Or perhaps the steel used for Model Y's lockbar is not always the same, so there may be no 100% accurate way to say what it is on any given knife.

Have there been any credible reports of the lockbar of a Spyderco front/mid lock rusting without the blade rusting? Of one breaking in normal use? Of excessive and premature wear to either the bar's pivot or engagement surfaces? Of one causing excessive and premature wear to the blade's engagement surfaces? I can't recall ever hearing any. From a purely practical standpoint, does it really matter if the lockbar is made of the same steel as the blade, "surgical stainless", or petrified bat guano - as long as it does its job?

[tap]

I guess I'll say it again. The lockbars are NOT made of the same steel as the blades. Spyderco uses a different steel for the two parts in order to prevent galling. At least, that is what Sal told us, and I'm fairly sure he would know.

My recollection is that Sal said they use a different hardness but he did not want to comment on specific lock steels on any models. So some models may use the same steels and probably most have a different steel. I have seen galling issues with a few of mine. It is hard to say exactly what started it on some of them. Some (ZDP-189 and ATS-55) do appear to have started because of imperfections in the steel with minor cavites from soft or really "hollow" spots. {Edit; Magnification used to examine.} Polishing tends to "cover" these cavites but they reappear in time. The only solution is to remove enough steel to get to the bottom of these cavities. If one surface has sever cavities in it and it causes damage to the other surface, is it really "galling"? Others (Byrds) have had bars that are/were not even close to being flat. That puts a very high contact pressure in one narrow spot.

[yablanowitz]

Actually, the term Sal used was "dissimilar metals". To me, that implies different alloys, as the same alloy with a different heat-treatment would still be a similar metal.

The problem you described is not galling as I understand it. Back in my Navy days when I was working with stainless steels and other alloys in the nuclear reactor plant, they taught us that galling was essentially two parts spot welding together through friction, leading to a material transfer from one surface to the other. It is more likely to occur if both pieces are made from the same material.