Possible bad heat treat on Sog Seal pup?

yepimonfire · Jul 16, 2015

Just picked one of these up, had to resharpen it 3 times in less than a week. Now I know it's aus 8a steel, which isn't king in edge retention, but about 75% of my knives are aus 8a, and they all will hold an edge for several weeks with my normal everyday use, this thing seems to go dull doing the simplest tasks. I've checked for a bur as well, it will easily cut phone book paper without snagging (which it won't do if it has a bur). I also have had issues with new knives needing a couple resharpenings to hold an edge, which I assume is because the factory belt grinding ruins the temper at the very edge, but this knife was reprofiled when i bought it far enough back this shouldn't be an issue. It went from hair whittling sharp to too dull to cut paper after filleting some chicken the other day, then this morning i broke a box down with it and same thing, literally was dulling right before my eyes, a bit of stropping and it's back to new.

Y'all think it's a bad heat treat? Anyone else had QC issues with sog?

PURPLEDC · Jul 16, 2015

Could be a bad heat treat but a burr cant still cleanly slice paper if the burr is straight and not rolled like the edge would be which most call a wire edge. It could also have been overheated during the sharpening process. In which many times the more you sharpen it the problem will fade as you expose new steel. No matter what the issue if its not keeping an edge yo your satisfaction i would contact sog. They should swap you for a replacement.

Boris74 · Jul 16, 2015

I've had a few SOGs in AUS8, all bought years apart. They all acted like what you posted. Now I know to stay away from SOG knives in AUS8. For some reason they just don't have a very good spec for it.

GatorFlash1 · Jul 16, 2015

What angle are you sharpening?

collim1 · Jul 16, 2015

GatorFlash1 said:
What angle are you sharpening?

I would like to know as well. If its not a heat treat problem, then maybe the factory edge is to thin. Maybe try a microbevel at a more obtuse angle.

I had a couple of Mora scandi ground knives that were ground way thin from the factory and rolled very easily. After a couple of sharpenings the edge got a little thicker and it started holding an edge well.

RevDevil · Jul 16, 2015

IF the steel is too soft, then it will need constant sharpening. Running steel a point or two softer than what is recommended can lead to poor edge retention but increased toughness. AUS8 isn't bad when done right, but when done wrong it's no better than mild steel used for welding.

me2 · Jul 16, 2015

There is more going on than the steel being too soft. I've tested annealed 1095 knives that did better than what the user describes. What is your sharpening procedure? Was this a used knife when you got it?

bdmicarta · Jul 16, 2015

Pick another of your knives that you think has similar geometry and good steel, a known quantity. Sharpen both knives to the same level. Get a supply of similar cardboard and start cutting. Cut a certain amount with each knife and then test sharpness of each one. Keep going until both get equally dull or until you can tell a significant difference.

Years ago I was buying a lot of custom knives and bought a small one from a maker I didn't know. I decided to try using the knife and wondered if it was decent steel and decent heat treat. I sharpened it and did some cardboard cutting, enough to prove that the knife had reasonable steel and heat treat and could be used.

yepimonfire · Jul 17, 2015

bdmicarta said:
Pick another of your knives that you think has similar geometry and good steel, a known quantity. Sharpen both knives to the same level. Get a supply of similar cardboard and start cutting. Cut a certain amount with each knife and then test sharpness of each one. Keep going until both get equally dull or until you can tell a significant difference.

Years ago I was buying a lot of custom knives and bought a small one from a maker I didn't know. I decided to try using the knife and wondered if it was decent steel and decent heat treat. I sharpened it and did some cardboard cutting, enough to prove that the knife had reasonable steel and heat treat and could be used.

Yeah, I'm comparing it to my ka bar mule, similar geometry, but the ka bar is thinner, it holds an edge marvelously for aus 8. The sog absolutely is not acting like a burring issue, I've dealt with enough to know what that's like, this is just pure deformation of the edge.....in the same way an edge dulls over time normally, just significantly faster than expected. With burrs they might cut paper once or twice, but once used it rolls right over and won't cut it at all or snags. This gets progressively worse on the paper, going from clean cuts to noisy cuts to ripping, after about 10-15 cardboard cuts it won't cut at all. My average for aus 8 is about 120-180 cardboard cuts before it fails to cut paper, this one is like 15 lol. Same with chicken, started out good, cut it effortlessly right up until the end. This was about 6 chicken breasts.

yepimonfire · Jul 17, 2015

collim1 said:
I would like to know as well. If its not a heat treat problem, then maybe the factory edge is to thin. Maybe try a microbevel at a more obtuse angle.

I had a couple of Mora scandi ground knives that were ground way thin from the factory and rolled very easily. After a couple of sharpenings the edge got a little thicker and it started holding an edge well.

The factory edge was 30 dps. I re-beveled it to 20 dps, which is more than adequate. Even my trailmaster has a 20dps edge and holds up well hacking wood.

me2 · Jul 17, 2015

So even with "good" AUS8, you're getting less than 200 cuts on cardboard before it completely fails to cut paper? What kind of cardboard is it?

Boris74 · Jul 17, 2015

The only thing that fixed my issues with SOG AUS8 hardness and quality specs was to forego using and getting rid of them. Even their flash II I had with their made in the USA cryo heat treat was a turd of a blade in AUS8. Seems I'm Not the only one to notice this issue. They do other steels right, but if I see a SOG in AUS8 these days, I pass.

SALTY · Jul 17, 2015

Boris74 said:
I've had a few SOGs in AUS8, all bought years apart. They all acted like what you posted. Now I know to stay away from SOG knives in AUS8. For some reason they just don't have a very good spec for it.

I had the larger SEAL 2000 knife years back. I remember doubting if it was heat treated at all.

:thumbdn:

KenHash · Jul 17, 2015

Never had a problem with any Seki made SOGs. And I own most of them. Doubt the Seal2000 would be on exhibit
at the US Navy UDT-Seals Museum in Fort Pierce Florida if SOG wasn't heat treating them. Can't really say about
the post 2006 Taiwan made Aus8A models though I do have a Seal Pup Elite and have been satisfied with it's edge
retention, but I do find it "softer" than the old Aus6A models.

yepimonfire · Jul 18, 2015

me2 said:
So even with "good" AUS8, you're getting less than 200 cuts on cardboard before it completely fails to cut paper? What kind of cardboard is it?

I think that's pretty good. Cardboard eats edges because it has impurities (I think clay like material) harder than the steel. Even my s30v blur only gets about 500 before giving up.

yepimonfire · Jul 18, 2015

Boris74 said:
The only thing that fixed my issues with SOG AUS8 hardness and quality specs was to forego using and getting rid of them. Even their flash II I had with their made in the USA cryo heat treat was a turd of a blade in AUS8. Seems I'm Not the only one to notice this issue. They do other steels right, but if I see a SOG in AUS8 these days, I pass.

It's too bad. The knives they make are really nice shape wise. I have another sog in 8cr that holds an edge well. I guess they just run their aus 8 a bit soft. If it weren't illegal I'd bring it to the college and test out the HRC of it. Idk where its at but my soft Hampton forge kitchen knives hold up better, and I'm supposing those are in the mid to low 50s. It's gotta be worse then that. This is like Gerber style bad heat treat, with a higher price tag.

me2 · Jul 18, 2015

yepimonfire said:
I think that's pretty good. Cardboard eats edges because it has impurities (I think clay like material) harder than the steel. Even my s30v blur only gets about 500 before giving up.

Here's where I start to wonder what's going on. I have used very inexpensive knives to cut thousands of feet of cardboard and never lost the ability to slice notebook paper. Thus my questions on sharpening and cardboard type. Why are we seeing such differences in performance with the types of steels we are talking about? I've cut dozens of feet (50' or so) of cardboard with knives that had blade hardness in the high teens to low 20's HRc and not seen the kind of performance drop you describe.

yepimonfire · Jul 18, 2015

me2 said:
Here's where I start to wonder what's going on. I have used very inexpensive knives to cut thousands of feet of cardboard and never lost the ability to slice notebook paper. Thus my questions on sharpening and cardboard type. Why are we seeing such differences in performance with the types of steels we are talking about? I've cut doezens of feet (50 or so) of cardboard with knives that had blade hardness in the high teens to low 20's HRc and not seen the kind of performance drop you describe.

I don't think you can even get a sharp edge at a hardness that low. And 50 dozen feet and still cleanly cut notebook paper? Are your knives made of glass or diamond? It's pretty much a unanimous agreement amongst knife people that cardboard is abrasive and has hard impurities that tears an edge up. If people could go through 50 dozen feet of cardboard, why would steel's like s30v or better be desired? That claim implies relatively soft steel hold's an edge for a very long time. Sure it might still cut things with alot of extra force, but notebook paper?
When I mention 120-180 cuts I'm typically talking 12" cuts or thereabouts. That'd put me at about 15 dozen on Aus 8, a steel that's not the greatest for edge retention. It definitely won't cut paper cleanly at that point for me. On s30v I can usually get to 25 dozen before it fails to cut paper, but beyond that point the s30v remains at that sharpness (which is still sharp enough to be right above the line i'd consider dull) for a very long time, don't know how long because I like to keep my knives razor sharp so it gets resharpened rather soon after it hits that point.

I've never had the kind of performance I've described on the sog with any other knife obviously either. If i've got a burr, it rolls immediately, this doesn't do that. It just goes dull at a rate much faster then my soft kitchen knives.

me2 · Jul 19, 2015

Edited my post for clarity. I meant 50 feet, not 50 dozen. 4 dozen. I can assure you a sharp edge on soft steel is possible, sharp enough to shave my arm at least. It took a few tries.

I just finished cutting 270 dozen feet of cardboard (3250') with a $6 knife. It would still slice notebook paper and would even cut a piece that was folded in half sitting on the edge of a table. Now, was it what I call sharp? No, not by a long shot. Would it still cut? Absolutely. I have a knife made from annealed (CRA) 1095 that was never hardened. I use it sometimes just to see what it will do. I may need to dust it off and start cutting again to see how long it can really go. Cardboard is considered abrasive, but it's not as bad as many people think. I laugh when I see a few people consider it abusive to cut it with a nice EDC.

yepimonfire · Jul 19, 2015

me2 said:
Edited my post for clarity. I meant 50 feet, not 50 dozen. 4 dozen. I can assure you a sharp edge on soft steel is possible, sharp enough to shave my arm at least. It took a few tries.

I just finished cutting 270 dozen feet of cardboard (3250') with a $6 knife. It would still slice notebook paper and would even cut a piece that was folded in half sitting on the edge of a table. Now, was it what I call sharp? No, not by a long shot. Would it still cut? Absolutely. I have a knife made from annealed (CRA) 1095 that was never hardened. I use it sometimes just to see what it will do. I may need to dust it off and start cutting again to see how long it can really go. Cardboard is considered abrasive, but it's not as bad as many people think. I laugh when I see a few people consider it abusive to cut it with a nice EDC.

I don't consider it abusive. Pretty much anything will dull a knife. Did you slice the paper against a surface or free hanging?