Sharpness of the Military

[Cliff Stamp]

Dan in regards to the Military it sounds like either the edge is rolling if you can sharpen it again that quickly. Or maybe you are leaving a wire edge on it which is quickly breaking off? What does the edge feel like when it blunts. Does it provide any more resistance if you wipe your thumbpad from the right - left than from the left - right.

As for the M2, yes, once it gets blunted it should take a bit of time to restore it to full sharpness. I have noted that it does resist the formation of a wire edge which may be the cause of the difference in performance.

-Cliff

 

[Dannyc]

Cliff,

Dan in regards to the Military it sounds like either the edge is rolling if you can sharpen it again that quickly. Or maybe you are
leaving a wire edge on it which is quickly breaking off? What does the edge feel like when it blunts. Does it provide any more
resistance if you wipe your thumbpad from the right - left than from the left - right.

Nope, there's no wire edge, I made sure of that. Remember the first time it got blunt? It was factory edge. I then resharpened it already, manually, making sure there's no burr or wire edge left. Resistance is the same on both, which I also made sure.

Strange, huh?

Dan

 

[Cliff Stamp]

Dan, that blows that out of the water then. It if is uniform then it can't be rolling which implies that it is actually wearing down that fast. Do you have anything else you could compare it to? I would be curious if even AUS-8 or 440A wore down at the speed you are seeing with the Military.

The only other thing I can think of is to raise the bevel a little and see if that increases performance. Maybe push it up to 25-30 or so degrees per side. Basically microbevel the actual bevel for strength. You should not have to though as it should hold an edge at a very low angle.

-Cliff

 

[Dannyc]

Cliff,

Funny you should mention that.

I did in fact have a couple of friends testing out some other knives in AUS-8 (a Master knife) and a 440A knife (Dragonforge Sensei). The AUS-8 knife was able to cut but also lost its edge pretty easily, so did the 440A. I just didn't include it here, because I was basically comparing the two tough steels which I was hoping would give me a good showing.

I don't even want to recall what my friends commented when they found out which one costs more.

Oh well... Since you're the all-time chopper here (hehehe, no offense) maybe you can give me some ideas on what materials to cut, and do more tests on?

As to re-profiling the bevel, I was thinking about that, too. But at its current angle, it might be a slow process to achieve that, and I might not be able to get it back to its original angle, as I'm not that proficient with sharpening yet.

The Sharpmaker or my DMT Aligner might help, though I'm afraid I might screw up the angle even more. Besides, shouldn't it hold its edge at the current factory bevel?

Dan

 

[Cliff Stamp]

Dan :

shouldn't it hold its edge at the current factory bevel?

Sure, assuming its reasonable, mine was. When I mentioned raising the bevel I didn't mean changing the whole thing. Its actually quite trivial to make a bevel more obtuse its making it more acute that's harder. If you want to increase a bevel that will be accomplished instantly with each stroke as you start off grinding along the edge. When you want to make it more acute then you first have to remove the shoulders before you even get to the edge.

what materials to cut

I would be interested to see if it can handle regular cardboard. The way you have described it I would almost expect it to blunt before you finished cutting a decent size box to strips. Something else I would be curious about is how it handles wire. The M2 blade should be able to cut fairly heavy wire without indenting and I would guess that a normal Military should do the same. If your Military indented significantly more than the M2 then that would indicate that it is probably too soft.

-Cliff

 

[Sal Glesser]

Dan - from the description, I would guess that the blade is soft (not heat treated properly). I sure can't resharpen my Military in 5 or six swipes. Even on the Sharpmaker, it takes some time. If it's soft, you won't get any decent performance no matter how you sharpen it or at any angle.

I have found that if a steel holds an edge well, it is equally hard to sharpen. The "giving up of it's molecules" works the same for dulling and sharpening. the steel doesn't know "what" is wearing away it's molecues or in what direction.

Cliff - don't know Rc of tested blade. It was a Stryker (I thought it was an AFCK, but I lied, Patrick said it was a black coated Stryker blade). I'll check for Rc tomorrow.

Dan - Danelle will contact you tomorrow to make arrangements to retrieve the "never should have made it past QC" model.
sal

 

[Dannyc]

Hi Cliff!

This sure is getting interesting, hehehe...

I would be interested to see if it can handle regular cardboard. The way you have described it I would almost expect it to blunt before you finished cutting a decent size box to strips. Something else I would be curious about is how it handles wire. The M2 blade should be able to cut fairly heavy wire without indenting and I would guess that a normal Military should do the same. If your Military indented significantly more than the M2 then that would indicate that it is probably too soft.

I'll try it on cardboard boxes. Regular corrugated cardboard ought to give it some workout.

Err.. Wires? Yikes... Depends on what wire we're talking about. I am thinking about battery terminal wires, the ones inside the car. I cut one up using my Leatherman Wave once, and it dented the hell out of the blade.

But since it's copper, it shouldn't be a problem with either the M2 or the 440V.

I'll do this tomorrow. Shop's closed already, hehe.

Dan

 

[Dannyc]

Hi Sal!

Dan - from the description, I would guess that the blade is soft (not heat treated properly). I sure can't resharpen my Military in 5 or six swipes. Even on the Sharpmaker, it takes some time. If it's soft, you won't get any decent performance no matter how you sharpen it or at any angle.

No kidding?? Hmmm... that's strange, coz I was able to do it, less than 6 even. So that must mean that the metal is soft. I didn't change the angle at all, just returned the sharpness back to where it was, or at least try to get the same sharpness as when it left the factory. There is supposedly no burr left when I'm done, though it bites a bit when I try to test it with my thumb. I'll try to blunt it with cardboard boxes as Cliff mentioned, and try to see if I can get it sharp again, and take note of how many swipes as before.

I have found that if a steel holds an edge well, it is equally hard to sharpen. The "giving up of it's molecules" works the same for dulling and sharpening. the steel doesn't know "what" is wearing away it's molecues or in what direction.

This is true. I never could figure out why some claim that their knives can be sharpened easily, and retain their edge for a long time without dulling... just doesn't make sense. If it can retain its edge long, then it would take a long time to get it back through sharpening once it gets dull.

Question, Sal.. Have this ever happened before? Coz from the reactions I get here, I assume that this is an eye-opener.

Cliff - Do I use a straight push cut on the cardboard? or do I use slicing action when cutting? Never thought this would be fun.. hehehe.. I'm getting lots of cut-up trash all over my house!

Sal, it's not really necessary, but we'll see what Danelle and I could work out on this one. Again, my sincerest thanks. I was just as surprised as most people here are.

Oh well, nobody said Spyderco was perfect, that's why we love your company.

Dan

 

[Cliff Stamp]

Dan, regarding the wires just start out with something light. For example I just took my Calypso Jr. and cut 15 sections of .5 mm copper wire and it made no visible effect on the blade. The knife will still push cut easily through paper. The important thing is to make straight cuts, if the blade twists then you will likely deform the edge. My mini-AFCK was used to cut significantly harder materials without excessive blade wear. As you noted, the knife steel should be a lot tougher than copper, pretty much only hardened steel should give it a problem.

As for the cardboard, push cuts will localize the wear and give a faster result as a blade has to be sharper to push cut well otherwise it will quickly start to tear into the material. Generally if there is nothing wrong with the knife and it is made out of a decent steel it should take a very long time before you want to resharpen it just cutting on cardboard.

After doing some cutting on boxes and such, to get an idea of blade wear I take strips of cardboard say 2" wide and rest one edge on my leg with say 6" hanging out unsupported. I then try to make a cut on the cardboard that is not resting on anything. If the blade is anything but very sharp it will just bend the cardboard. Of course the exact numbers depend on the stiffness of the material and such, but it is a relatively quick way to judge blade wear and it can be duplicated trivially by anyone wanting to do a comparasion with one of their knives.

-Cliff

 

[Dannyc]

Got it, Cliff.

Thanks. I'll try to test those materials out as soon as I can. I can't tell the gauge thickness of the battery wires I have at the shop. I'll look for something smaller to start it out with.

I just hope I don't deform the edge or anything.. hehe..

Dan

 

[Dannyc]

Cliff,

Just finished cutting up the cardboard (boxes). So far, both knives performed okay, no winner in that department.

But the wire-cutting is another story. As usual, my AFCK-M2 was able to cut through with no dents whatsoever. However, when I tried cutting it with the Military, it snagged halfway, and didn't want to cut through. I didn't push through with it, for fear of denting the blade. It just doesn't want to cut metal wires. So I guess the steel is soft.

Oh well.

Dan

PS. I just checked the edge on the Military, and true enough, there is a very small dented part on the edge. Aghhh...

 

[Jeff Clark]

It sure sounds to me like the heat treat on that knife is very defective. You should probably just send it back. I don't think you'll learn anything useful by continuing to play with it. Maybe Sal will reimburse you for your shipping charges. It should never have gotten out of the factory in the condition you describe. The only time I've had a knife that bad was back when I was 11 years old and heated a paring knife until it glowed over mom's gas range. I annealed the hell out of it. Mom annealed me pretty good too.

Oh yeh, back 30 years ago they exported some lock-back folders from Pakistan that were that bad, but they cost less than $5.00 each.

[This message has been edited by Jeff Clark (edited 22 July 1999).]

 

[djo62]

Dannyc
Sal and I would both like to get it back in the office here.....will you send it in?
Danelle

 

[Dannyc]

Jeff - lol... mom annealed you pretty good, huh? hahahaha..

Well, I was just testing it to see if it's really the heat treat, or just the grind that's defective. Cutting cardboard doesn't seem to be blunting it a bit, but the wire thing is something else. I'll stop playing with this now.

Danelle - I'll try, but probably not now. I'm a bit short in funds, with my daughter's tuition and all. I'll keep it in mind though. Heck I can't even send in my registration card for that free Sharpmaker video.

Dan

 

[Cliff Stamp]

Dan your results are interesting as I would have expected it to dull fairly quickly if there was a problem with the blade. Can you compare the Military to the following [Calypso Jr.] :

To get some numbers I cut up some 1/8" cardboard. It took 60 13" slices along the ridged grain to reduce the edge from shaving sharp to below scraping sharp (enough pressure to shave will scrape skin as well as hair from your arm). As this point the blade will not easily bite into the cardboard unless it is very stiff, the edge tends to slip a little and sometimes tear the material during a cut. The edge was easily restored after this though. It only required about 15 strokes per side with an 800 grit ceramic rod. I then made another 30 13" cuts, this time against the grain, and again the shaving sharp edge was lost. I tried the ceramic rod again, but 25 strokes per side only got it up slightly past scraping sharp. The edge had degraded enough to want to be sharpened. However it grinds very easily and only about 15 strokes per side on the ex-fine DMT pad was enough to get it back to shaving sharp again.

What I am wondering is something that has been discussed before. The 440V Military is fairly soft compared to most folders. I recall it being in the 55-57 RC range. Assuming you have one of the softer ones I could see the edge having the tendancy to roll easily or even indent. However given the high wear resistace of 440V, it should be able to cut soft materials for a long time. This is pretty much exactly what you have described.

-Cliff


[This message has been edited by Cliff Stamp (edited 23 July 1999).]

 

[Dannyc]

Cliff, you're right.. It does cut through softer materials for a long time with no apparent problems. It's only with hard materials that it's showing its "faults".

I don't think I reached the 60 cuts on the cardboard, but I believe I went past 40, and it's still cutting, though not at 13" strips.

Danelle wrote to me already, so it's just a matter of time before I send this one back for replacement, if ever.

I've already ordered a Starmate as of this writing, so hopefully things will be better from hereon in.

Dan

 

[Mitchell]

Uh-oh, someone in QC is in trouble.

Just kiddin!! Hey Danny you need to get the knife in for an inspection. I work in a design validation/qc lab and you are probably giving them conniptions (sp). That knife really needs to get looked at. You might want to get the the apporx date and location it was purchased. This will help in tracking down any other bad ones. And I'm thinking about buying a Military and am curious about this outcome.

Mitchell


[This message has been edited by Mitchell (edited 24 July 1999).]

 

[Dannyc]

Mitchell,

Don't hesitate on getting yourself a Military. Even if I got a lemon, that doesn't mean a thing at all with regards to the Military's prowess as a knife, as a whole.

To show you how much I still trust Spyderco, I ordered a Starmate, which is also in 440V steel. Stubborn? You bet!

hehehe... But I'm not going to buy it locally, unlike the Military I got. I'm ordering it online once again.

A good friend of mine, and a fellow forumite, Titan, won a Military a few months back, and has had no problems whatsoever with regards to the cutting ability of his Military. And take a look around you, you'll see tons of other people satisfied with their Military knives. I'm just unfortunate enough to get one of the few bad ones around. But don't let that make you think twice, Spyderco's QC control is top notch, but human otherwise, so lemons do sneak out once in a while. If you're located in the States, then don't even worry about it, as the company will take care of you, I'm sure.

Dan