Help me understand INFI

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David Mary

David Mary

pass the mustard - after you cut it
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I don't know much about INFI. But I looked at Larrin's toughness chart for A8MOD and see that he has it at about 40 ft-lbs. Okay so about the same as AEB-L. Is INFI about the same? Is BUSSE toughness a factor of special heat treatment, or geometry? When I grind an AEB-L chopper at 61 RC to .016" behind the edge, it demolishes hard wood. Wouldn't want to chop cinder blocks with it though. But if I ground the same AEB-L chopper to .035" behind the edge, I suspect it would do that just fine.

So to help me understand:

Let's say that for abrasive wear resistance, Maxamet is a ten, and 8Cr13MoV is a three. What is INFI?
Let's say that for corrosion resistance, LC200N is a ten, and 1095 is a three. What is INFI?
Let's say that for toughness, S7 is a ten, and ZDP-189 is a three. What is INFI?

This thread made me want to finally ask about this:

 
my first post here was asking about infi....what I remember without going to look it up...was a patent on it along with an involved proprietary heat treat process. some talk by some folks of it being a lot of marketing....dont remember anything else. seems most folks that have Busse and brands knives in it, seem to really like it. I still dont have one, never used one.....so i dont have a personal opinion from firsthand use.
 
Idk how many infi squabbles I've been in on this forum. Lots. This question pops up every few years, sometimes multiple times a year.

I've had infi for 10 years and been using 3v for I'm not sure how many, 7 maybe. I've bent infi to the point it took a set, and beaten infi more than most steels will handle.

I have infi that's rusted and I have 3v that's rusted. I haven't used 3v as hard as infi, as I don't think anyone will warranty that level of abuse. But I've beat 3v plenty hard. My opinion from a user prospective is 3v and infi will both rust close enough that I don't think it matters but like said above 3v probably has a slight edge. Edge retention goes to 3v and toughness to infi. Toughness being that it will deform instead of snap.


Without turning this into an essay, I'd rate infi 8 in toughness 6 in stain resistance (if 1095 is a 3) and a 5 in Edge retention.

The combination of extreme durability, good designs and ergos and a warranty that covers everything but intentionally destroying the blade with a torch make busse still competitive. Yes, other steels are providing competition and other companies are making very durable blades, which is good. Competition is good. Variety is the spice of life.

So no, infi isn't obsolete.
 
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shinyedges said:
Idk how many infi squabbles I've been in on this forum. Lots. This question pops up every few years, sometimes multiple times a year.

I've had infi for 10 years and been using 3v for I'm not sure how many, 7 maybe. I've bent infi to the point it took a set, and beaten infi more than most steels will handle.

I have infi that's rusted and I have 3v that's rusted. I haven't used 3v as hard as infi, as I don't think anyone will warranty that level of abuse. But I've beat 3v plenty hard. My opinion from a user prospective is 3v and infi will both rust close enough that I don't think it matters but like said above 3v probably has a slight edge. Edge retention goes to 3v and toughness to infi. Toughness being that it will deform instead of snap.


Without turning this into an essay, I'd rate infi 8 in toughness 6 in stain resistance (if 1095 is a 3) and a 5 in Edge retention.

The combination of extreme durability, good designs and ergos and a warranty that covers everything but intentionally destroying the blade with a torch make busse still competitive. Yes, other steels are providing competition and other companies are making very durable blades, which is good. Competition is good. Variety is the spice of life.

So no, infi isn't obsolete.
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I’d give OG recipe INFI these marks:

Toughness: 8-9
Stain resistance: 7
Edge retention: 7

Agree 100% with your scores on the newer version. I prefer SR101 over the new INFI and even over the original stuff in smaller knives. Holds an edge better but not as tough. Can’t believe they discontinued it.
 
I think you should look at A8(mod) for the best comparison. That's what the composition is closest to. Who knows about the heat treat.

A8(mod) will be one of the toughest steels, but not in the league of S7 and a bit short of 3V.

For wear resistance, it will be pretty low, between A2 and AEB-L.

A lot has to do with blade geometry. Busse makes pretty brutal edge/blade geometry, so those knives can dish out a real beating. When I compared Delta 3V to Infi in a chopping test of bailing wire -- with edge geometry matched -- the results were pretty close. I have a Knife Research A8(mod) blade with a long, involved custom heat treat that can actually chop up rocks. There's a video of a bunch of Italians doing just that and being surprised by the lack of damage.

I don't know about stain resistance. Vanax is the king there. But the kind of rusting matters. Something like M4 will pit. 3V will sheet rust, making it easy to clean off. I don't know about Infi.
 
AntDog said:
I’d give OG recipe INFI these marks:

Toughness: 8-9
Stain resistance: 7
Edge retention: 7

Agree 100% with your scores on the newer version. I prefer SR101 over the new INFI and even over the original stuff in smaller knives. Holds an edge better but not as tough. Can’t believe they discontinued it.
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No more sr101? Wth!
 
shinyedges said:
No more sr101? Wth!
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Yep, discontinued! Something about the company that made their heat treating ovens going out of business so they’re all broke except a small one.

We Bid Farewell To SR-101 Steel . . .

SR-101 has left the building! We must, for the foreseeable future, bid farewell to SR-101, the legendary steel used by all four of the Busse Kin knife lines over the past 20 years. SR-101 requires a very advanced oil-hardening heat-treat protocol. This protocol includes a very specialized...
www.bladeforums.com www.bladeforums.com
 
INFI's relatively unique quality is in durability and reliability under hard use, rather than pure toughness. When I'm doing something abusive with a knife (e.g. chopping hardwood with a sloppy technique so that the edge is impacting at an angle, and hitting the occasional nail or small rock) I'm not worried about the blade snapping in half or giant chips. I'm worried about micro-chipping or mircro-rolls that eventually would make it unusable as a knife (i.e. too blunt to cut with). INFI resists that kind of micro edge damage - with a good balance between resisting chipping and rolling - better than anything else I know (with the possible exception of D3V). And when it does get damaged, it's so easy to sharpen that it can be repaired quickly.

So with INFI I know that I can repeatedly / long-term abuse it without worry. And only a small amount of work is required to maintain it at that level of performance. No major regrinds required.

It loses it's fine edge faster than many other steels when it comes to normal cutting use, but when you need a 'sharp enough' edge for abusive cutting or chopping it maintains it almost forever.

fishface5 said:
It's curious that Busse would change their INFI recipe to an inferior version??
Click to expand...

I've got both the old and new recipe. The old recipe was harder, had better edge retention, but possibly at the expense of toughness. The newer recipe is about two points softer, has less edge retention, but is probably tougher - and cheaper. So it's not worse, just a different balance of qualities. If I had to guess, I'd say Jerry made a call that that mix of qualities was better suited to what his customer base wanted.
 
INFI is real deal. Nothing magical like someone might want you to believed but it’s definitely a great beating steel with excellent over all attributes. The Busse edge might be thick for non-beating tasks by the way.
 
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