Edge problems. My fault, sharpener's fault, or BM's fault?

Aphthartos · May 29, 2001

I'm selling an AFCK here on BF. It has a problem with it and I want to ask you guys about it. Here's the story. I hadn't used it much in the couple years I had it, carried it off and on, though. I finally started using it about a month ago, and got it dull, so I sharpened it, working it down to what's now a 30degree angle(i think)on both sides with a lansky system. But now the back edge of the blade(clip side) looks like it's at a flatter angle than the front edge(i.e. back edge = 30, front edge = 20-25). I had originally thought it must have been BM's fault, then I noticed a couple days ago that my dad's knife, a BM 330 that I got him for christmas, or maybe his birthday(heh, can't remember exactly), which I sharpened for him with the same Lansky system, had EXACTLY the same problem, so then I thought it was the lansky, but(again!) I just recently(in between sharpening my dad's and sharpening my own) worked the angle on my Kershaw Whirldwind down to 20degrees and I noticed just tonight that IT DOESN'T have that problem. I was careful not to oversharpen either side of the blade, sharpening evenly on each side throughout, and my dad is no different. So, does it sound like BM's knives are the problem, the Lansky system, or me? If it's BM's problem I'll cancel selling it, and send it to BM for a blade replacement. If it's my problem, or the lansky, then I'll just try to sell it and buy a new sharpener(yes, probably an edgepro). Fortunately my dad's knife had OTHER problems which necessitate a blade replacement, so he's fine in either case.

On second thought I think I'll take it down now. Just to avoid the possibility of false advertising

So what do you think? Anyone else had the same problem?

OwenM · May 29, 2001

Originally posted by Aphthartos:
...so I sharpened it, working it down to what's now a 30degree angle(i think)on both sides with a lansky system. But now(italics mine) the back edge of the blade(clip side) looks like it's at a flatter angle than the front edge

Looks like you did a number on it.
You're sharpening it at 30 degrees per side??? That would make for an extremely thick edge. AFCK does well with 30 degrees included (15 per side-more like the 17 setting on the Lansky), in my experience.

My personal experience with the Lansky was not good, and I only used it for reprofiling. Gave it to a friend, and he has no problem getting great edges with it. Go figure.
Sounds like we could both use a little lesson in "Lansky technique"

Aphthartos · May 29, 2001

Sounds like we could both use a little lesson in "Lansky technique"

Had the same system for 4 years and haven't had a problem till now. I may have bad technique but it's a recent development, if that's the case.

You're sharpening it at 30 degrees per side??? That would make for an extremely thick edge.

Yep it does, but it was easier for me, at the time, and took less time to work it to 30 than to work it to 15 or 20.

[This message has been edited by Aphthartos (edited 05-29-2001).]

Aphthartos · May 29, 2001

Solved the problem, at least from my POV. I decided to give the knife to my dad as a hard use knife, he doesn't care about such things.

glockman99 · May 29, 2001

Since you have "solved" your problem by giving the knife away, I suggest that you also give that Lansky kit to your dad, and buy yourself a Spyderco Sharpmaker.
...End of future "problems".

.

------------------
Dann Fassnacht
Aberdeen, WA
glockman99@hotmail.com
ICQ# 53675663

Aphthartos · May 29, 2001

The sharpmaker-like systems don't work for me at all. Might as well just get a normal stone for freehand sharpening. Cuz neither type works for me. :| 5 years and I have yet to put a decent edge on a knife with either type of sharpener. I guess I don't have the "voodoo" that some say you have to have.

bad4u · May 29, 2001

I have both the Lansky system and the Sharpmaker system. I stopped using the Lansky system quite a while ago due to the tedium of clamping/unclamping/moving/re-clamping...

Most often I use benchstones for profiling or re-profiling an edge, followed by stropping for polishing with an aggressive grit and then final edge polish strop with 10000-grit abrasive powder.

The really strong feature of the Sharpmaker system is that - assuming one can hold the blade vertical - it's almost impossible to produce non-symetric final edge angles.

Thus, even when using the benchstones, I keep the Sharpmaker handy for checking that I'm honing equal angles on each side of the blade edge.

I don't think you've 'ruined' your Benchmade with non-symetric edge angles, and I suggest that an investment of an hour or so with a Sharpmaker would restore a symetric edge.

MAURICE · May 29, 2001

yeah,30 degrees is pretty thick.
i think one of the best ways to shapren would be something like a sharpmaker 204,with the sharpening sticks set at a certain angle,and all you have to do is draw the blade across.versy simple,very little chance of error.

Aphthartos · May 30, 2001

The really strong feature of the Sharpmaker system is that - assuming one can hold the blade vertical - it's almost impossible to produce non-symetric final edge angles.

Yeah, but that's the problem right there, it's no easier for me to hold the blade vertical than it is for me to hold the blade at 20 degrees or something. I have been trying a bit lately, because I plan on getting some water stones, and I will if I can get at all decent at sharpening freehand. I did manage to put a decent edge on a little spyderco I have with a bench stone, but putting an edge on a Spyderco is like putting butter on bread, it's near impossible to screw up.

Shawn R Sullivan · May 30, 2001

Aphthartos,
Did you sharpen one side of the knife untill you had a burr and then switch to the other side untill you had a burr? If you did that would explain the uneven edges. You removed a bunch of material from one side of the blade and moved the cutting edge from the center of the blade. Then when you started sharpening the other side of the blade you removed less material to get the burr. Does this made sense? To keep the edge even, the start on a different side each time you sharpen the knife.

Shawn

[This message has been edited by MrCas (edited 05-30-2001).]

May 31, 2001

Hi there,
When using any clamp-on type sharpener such as Lansky or DMT or Gatco you have to watch for 4 possible errors:
1) you have to use "about" the same number of strokes on each side, so the edge will stay in the center of the blade. Hint: I'm counting the strokes...
2) you have to use "about" the same pressure on both sides, sounds easier than it is...
3) you have to use the same angle on both sides. Very easy, but "things" do happen...
4) Using "Gatco" you will see, that when adjusting to the thickness of the blade, the "jig" moves one way only, which makes the blade slightly asymetrical. Lansky and DMT do not show this effect.
Happy sharpening

------------------
Ted

Frantium · May 30, 2001

Okay here's another perspective:

Having 5 AFCKs so far and a handful of Eclipses/Ascents with similar blade geometry, I can say that most of them don't have exactly the same grind between the left and the right sides. I have an early AFCK with exactly the same problem no matter what sharpener I use (including my brother's EdgePro Apex), the others aren't so bad. That's why I always compare the left grind from the right grind when buying a knife with the said geometry. At one time at AG Russell's it took about 8 AFCKs before I decided on one. I must also mention that my latest AFCK was acquired almost two years ago, so they probably have fixed the problem.

Another thing: are you sure you positioned the knife's spine at exactly the notch of the clamp? A couple of friends who have Lansky rigs said they were having problems of inconsistency when sharpening knives. It turned out that they clamped the knives at the wrong spots.

------------------
Reynaert

Keyman · May 30, 2001

Blade shapes,like any modified spears, need extra care when clamping with lansky.

------------------
-mike
Life is too short to stay on idle, don't be afraid to use that throttle.

Aphthartos · May 31, 2001

Did you sharpen one side of the knife untill you had a burr and then switch to the other side untill you had a burr? If you did that would explain the uneven edges. You removed a bunch of material from one side of the blade and moved the cutting edge from the center of the blade. Then when you started sharpening the other side of the blade you removed less material to get the burr. Does this made sense? To keep the edge even, the start on a different side each time you sharpen the knife.

I was very careful to remove an amount of steel from each side that was as even as possible. I know the little burr trick and actually read the sharpening FAQ before I screwed up the edge on this knife. Note: the FAQ had nothing to do with me screwing it up.

ZUT&ZUT: Thanks for the info, #4 I knew nothing about, I'll avoid GATCO sharpeners.

Frantium: that was my idea about this blade, I figured since it showed up just on my AFCK, and my dad's 330 and the fact that they have a similar grind(i.e. with the semi-false edge at the top), and that it didn't show up on OTHER knives that I had done the same thing to(before, between, and after), might count as evidence of bad blade shape. Others seem to disagree, though. At any rate, do you think it's worth sending to benchmade and getting their opinion on it/possible blade replacement? There's uneven grinds on my dad's 330(I know, I can SEE them), so his blade is as good as replaced, but should I bother with my AFCK? Would that be something they would even consider being under warranty? Am I being obsessive?

Another thing: are you sure you positioned the knife's spine at exactly the notch of the clamp? A couple of friends who have Lansky rigs said they were having problems of inconsistency when sharpening knives. It turned out that they clamped the knives at the wrong spots.

Yes-indeedy. I'm always very careful of that.

Maybe I can go further in explanation. I can't remember the technical name, but the blade is ground into a sort of spear shape, with the top having a sort of false edge. You know this, but I'm explaining. The "spear" grind makes a line on the blade that meets up with the line made by the top of the edge, the two lines meet up at the point of the blade, right? Well the back side of the blade doesn't do this, it turns out more like a hollow ground blade sharpens up, the edge is of even "width" all along the curve of the blade, and the two lines meet up a good 1/16th of an inch BEFORE the tip. While the front side is just fine, the two lines meet up at the tip.

Here, I tried to draw a picture in PSP, I'm no computer artist, feel free to laugh at my expense.

Funny lookin, eh? Same thing on my dad's 330, on exactly the same side, and I can't reproduce the same look on the other side, even reversing the knife in the clamp.

Frantium · Jun 1, 2001

Aphthartos,

Yup, that's what I was talking about and your picture has explained it. It is usually clearer when you see at your knife with the tip facing you.

I bet e-mailing or calling BM is your best bet, as it is a matter of bad grind. Its lifetime warranty IMO should cover this. I don't use guided sharpener as often as I used to, so I usually can compensate when sharpening with benchstones.

OwenM · May 31, 2001

I completely forgot to mention that BM has the Lifesharp guarantee, and will resharpen your knife for you.

Aphthartos · May 31, 2001

Yup, that's what I was talking about and your picture has explained it. It is usually clearer when you see at your knife with the tip facing you.

Yeah, it is. It's interesting to note that the edge remains pretty well centered when compared to the rest of the knife, but it's just the angle of the edge, and the shape of the tip that differ.

I bet e-mailing or calling BM is your best bet, as it is a matter of bad grind. Its lifetime warranty IMO should cover this. I don't use guided sharpener as often as I used to, so I usually can compensate when sharpening with benchstones.

I did call them, man, I love BM's customer service, such friendly people! But I didn't want to spend the money sending it back to them without first being pretty sure it would be something covered under their warranty(i.e. I wasn't the one that messed it up, or it wasn't the sharpener's fault, hence the title of the post).

I completely forgot to mention that BM has the Lifesharp guarantee, and will resharpen your knife for you.

Great service, and I knew this, of course. But 5 bucks and 5-10 days is bit of money and quite a wait. Not that I don't have other knives that would fill in for the AFCK while it was gone

I think I'll go ahead and send it in. I'll at least be able to get their opinion, and possibly my dad will get a like-new AFCK(the only problem was with the blade, the rest of the knife's in basically perfect condition} and he'll get a new blade on his 330.

A side note, I gave it to him and he thought it might be a little big, he carried a pager, a cell phone, snuff, his wallet(very large wallet), keys(a lot of them), a gerber multitool, and change around in normal Levi 501s. So he thought he might not have enough room, but after using the AFCK for two days he's MADE room in his pocket. He loves the knife and has shown it off to the guys where he works. The asymmetry of the tip has made it sort of brittle, though, so I hope I can get the blade replaced for him. It's the first "real" knife he's had, if I had known how much he would like it I would have given it to him before it got weird.

Edge problems. My fault, sharpener's fault, or BM's fault?

RIP Dann, you were a good guy.