SM-100

Legacy Forum Archive General Discussion (Legacy)
1

Hey guys, I have a Ferrum Forge Stinger I bought new about 2 1/2 years ago. It’s blade steel is SM-100. I guess I shouldn’t call it steal really, from what I’ve read about it. But I was wondering if anyone has ever tried sharpening this stuff. I have it in my vise and have started to find the sweet spot and then it popped in my mind, that this stuff is harder than anything I have ever heard of and might want to check on here with guys and see if has any advice. I mean, nasa tried squashing it with their press made to squash bearings, which supposedly tops out at 2,000,000 pounds and they couldn’t hurt the SM-100 bearing. Also, it doesn’t have any metal in it. A magnet has no attraction to it what so ever. So, will my WE stones be able to put an edge on this thing, or will it ruin my stones trying? Let me know if anyone has any experience with this stuff or has any thoughts on it.

 

 

2

Jon J,

First time I’ve heard of this alloy and have not had a chance to sharpen it. I went to http://zknives.com/knives/steels/sm-100.shtml to look it up. Zknives is a fairly good reference for different blade steels - but buyer beware - it’s one persons opinion.

Ed K.

 

SM-100(Summit Materials) - Variation of the Crucieble NiTiNol 60 alloy. Composition was tweaked to improve manufacturing process, but exact numbers have not been published yet. Promotional materials refer to NASA tests and mention twice the life expectancy compared to AISI 440C, although the tests were done for bearings, not knives. Not sure why, but even Summit Materials own web page cites two different working hardness ranges 56-62HRC on the materials page and 57-64HRC on the home page. 2 HRC especially when we’retalking about 62 vs. 64HRC can translate into huge difference in edge holding, edge thickness etc. I’m trying to get more precise data. NiTiNOL knives are speced at 65HRC. Another point to consider, alloy has very low Young’s modulus value 47-90 vs 200 and above on more conventional steels. Can’t tell without testing an actual knife, but low Young’s modulus could affect edge stability and strength negatively. In other words edges might require extra thickness to sustain themselves, which would definitely be a negative. Other Titanium and Cobalt alloys such as Talonite and Stelitte 6B, Stelitte 6K have the same problem with thick edges. Keep in mind, this is purely a guess, based on a particular property.

Manufacturing Technology - CPM

Country - United States(US)

Added the NitiNol 60 entry as well.

60 NiTiNOL PM(Crucible) - Crucible CPM alloy, 60% Nickel, 40% Titanium. Discovered in late 1950s, by US naval ordinance lab, which is why we have NOL in the alloy name. Has many potential uses, however manufacturing process is very complicated and expensive. Obviously, very expensive blade material. So far only one maker uses it. Hardness up to 65HRC. High wear resistance, corrosion proof. Variation of the NiTiNOL appeared recently, SM-100 by Summit Materials, LLC.

Manufacturing Technology - CPM

Country - United States(US)

Known Aliases:
Crucible - NiTiNOL60, Crucible - NiTiNOL

 

ttp://zknives.com/knives/steels/sm-100.shtml

3

I had never heard of this material either. It should be okay to sharpen with the diamond stones since there is no way this stuff is harder than the diamonds.

4

I agree that diamond stones should be able to sharpen anything, and Rockwell numbers in the 65 range ought not to be a problem. My ZDP-189 Spydies should be at about Rc64 and I’ve had no problems sharpening them. Carbide tooling can be sharpened with diamond stones too, but one must take care not to apply too much pressure. When the diamond particles are under high lateral loads, the nickel plating attaching them to the substrate could fail.

5

I talked with the maker of the knife, Ferrum Forge, which is 2 brothers, 1 of whom is extremely knowledgeable about this material and he suggested that I send it in to their recommended sharpener, but I’ve got a WICKED EDGE and that’s not about to happen. So he said to make sure and keep the stones clean, cause they will fill up quite quickly with the SM-100 material.

Also, if you know nothing of this material, you might look it up, pretty wild. I remember before I bought this knife, I read on the Ferrum Forge website about all the troubles they had with making the blades. It’s pretty unbelievable stuff.

6

Having had a very little bit of exposure to titanium, I can imagine that it would tend to plug up abrasives pretty rapidly, much like aluminum. A trick I was taught by an old machinist is to rub chalk on a file to prevent aluminum from plugging up the teeth.

That said, I wouldn’t expect a hardened version of the material to act the same, but here we have someone with experience contradicting that idea.

7

As per Mike Emler, do NOT use diamonds on SM-100. Just got a Stinger in SM-100 myself but it’s off for repair so I haven’t had at it yet (I’m a TSPROF user BTW).

You don’t even want to use CBN, just silicon carbide I think. The guys at Ferrum actually just use sandpaper to sharpen their stuff.

 

It will load up fast, and diamonds don’t work on it.

 

You also have to consider the manufacturing process of your specific piece, as this can’t be forged into bar stock under anything resembling normal metallurgy common to carbide-containing metals. It has to be made in a vacuum among other things with knowledge probably only NASA truly understands.

 

From what I have read, it’s plenty good as a blade with zero corrosion and acceptable other properties including edge retention when sharpened “properly”,.

 

 

8

May I ask what the reasoning was for not using diamonds to sharpen this material?

9

Good question- his official reason was “The stuff does NOT like diamonds”. I think that they A)load up really fast and B)cut in a way that does not leave a refined edge no matter how small the grit.

I’m only guessing here, but since this material doesn’t have carbides, vanadium, etc. a good edge may be the result of gently bending the apexes together as opposed to leaving the ideal (but unachievable) 1 atom wide (or would it be 1 angstrom high?) vanadium carbide “teeth” the entire length of the blade’s edge.

Sorry I can’t be clearer- I don’t have any real world experience sharpening the knife yet.

10
11

Who is this guy?

12

His name is Micheal Emler with his channel “Crazy Sharp” . I’ve never see or heard of him before. Nor do I know anything about the knife or steel. I surmise he’s just another of many knife and knife sharpening enthusiasts that post YouTube videos vying for your subscriptions and support.

 

13

Looks like more of a podcast with people joining in and asking questions.

14

He’s a little more in that he does the custom sharpening for Ferrum Forge and has a bit of a following in some circles at least. He does everything freehand, don’t know how I feel about that as a guy that values precision and repeatability, but for people that don’t know how to sharpen knives and are willing to pay $30 for someone else to do it he does pretty well for himself.

Also a heck of a nice guy, when I asked him about the SM-100 he gave freely of his time even though I wasn’t a customer.