knife sharpening...what am I doing wrong?

Runs With Scissors

Runs With Scissors

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Dec 3, 2000
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Here's the story: I've got a Victorinox Adventurer Swiss Army Knife I've carried since 1992, I've flirted with many others, but that has ALWAYS been my most well used and loved standby knife. As you can imagine after ten years of use, the blade is a wee bit worn, but I'm wondering if I'm being insipid, or if the knife has...changed somehow with years of wear and tear.

No matter what I try on the knife it will NOT take the hairpopping edge that it once seemed to have. It can't even come close to my Victorinox Tinker I bought a couple months ago. I can get it kinda to the point of where it more like pulls hair out of my forearm, but never hairpopping sharp. And even then I can put it away for two weeks, take it back out and it seems like the darn thing gets dull sitting in my closet.

I've had it professionally resharpened, with a slight improvement on the initial edge, but still zero edge retention.

Tried the Sharpmaker at 30 and 40 degree angles

Tried another set of crock sticks at 25 and 45 degree angles

tried a traditional whetstone at all forementioned degrees

ttied stropping it lightly.

Nothing has worked! I sharpen all my other knives without even a minor problem, but this one is kickin' my butt! what am I doing wrong, if anything? is it time to retire my rusty, trusty SAK? If so, what's happened to it? I know that may very well be the logical thing to do, but this cheap litle every day knife means a heck of alot to me, and I kinda wanna hang onto it.

So, what's broken? me, or the knife?
 
Okay, let's start with the basics. My apologies if you've done all this already.

- When you sharpened it on the Sharpmaker at 30 degrees, did you grind one side only until a burr appeared along the entire length of the other side, then switch sides and repeat? (i.e., throw out Spyderco's instructions, and sharpen it like the big boys).

- Did you use a magic marker on the edge to gauge your progress and ensure you were actually making progress?

- Once you'd generated a burr, first on one side, then on the other, did you then switch sides between strokes, lightening your strokes as you went on and switched to finer stones?

- When you were done, did you pop in the 40-degree stones and take one or two very light swipes per side (no more pressure than the weight of the knife itself) to finish off whatever might be left of the burr?

If you did all of the above, it's nearly inconceiveable that your knives aren't coming out sharper than they came from the factory!

Let us know what you did, and how you did it. Just being old shouldn't make the steel perform worse.

Joe
 
There is something going on because it happened to me much the same way. I've got an Adventurer that I've carried daily for around 10 years. It seems like for the last couple years it has been very difficult to put a screaming edge on it. I have sharpened knives professionally and know all the general tricks. Somehow this blade doesn't want to become a razor.

I have thinned the edge using diamond hones, honed it with aluminum oxide, silicon carbide, diamond, water stones, oil stones, razor hones, hard&soft Arkansas stones, india stones etc. I have steeled the edge and stropped it with various strops and polishing compounds. None of those things produced an edge that was up to my standards anymore. I don't know what is funny about the core of this blade, but it doesn't work the way the first few millimeters of edge used to. And like I said, I have thinned the edge down to around 10 degrees.

Now the funny part. For Father's Day I went out and got myself another sharpening system--one that is common enough in these parts, a Sharpmaker. I took my knife and freshly thinned the edge using a fine diamond hone. Then I finished the edge with a few strokes on the Sharpmaker's medium stones. This yielded an edge that did a very credible job of shaving. I went back and stropped it a little and I am now reasonably satisfied (well actually I am never satisfied, but at least I'm not unhappy).

A couple weeks ago I was thinking of posting a thread asking people what hone worked best for them on old Victorinox SAK's. One reason I got the Sharpmaker was that I knew that was going to come back as the number-1 answer.

So what is the mystery? Did Victorinox put some odd/bad steel in there longer locking-blade models back in the early 90's? I don't know. If the knife shop that I visited on Father's Day had a good Adventurer in stock I would have bought that instead of the Sharpmaker. I'll probably do that soon, but for less money on the net.

I don't know why I had better luck than you did with the Sharpmaker. My primary work was with a diamond hone and I only finished the edge with the medium rods. The rods were new, therefore clean. You might try a diamond hone first and then clean your medium rods with sink cleanser before you use them.
 
PS. I guess the most conspicuous thing that I did differently was to back bevel at 10 degrees. For a worn blade like this I wouldn't simply use the 15-degree rods alone. I want the blade thinner behind the edge.
 
I've also seen "professional sharpeners" ruin a knife by letting the edge get too hot on a hi-speed belt or wheel. Results in the effect cited above, a credible edge, but no edge retention to speak of. Otherwise, after years of sharpening, and without significant thinning, it might just be too thick behind the edge for you.
 
Blades will harden to different extents depending on the thickness, however I have only seen this addressed with much larger blades (~1/4" thick). If your method is producing quality edges on other blades, the fault it probably with the knife.

Regarding angle and edge thickness, both of these have a significant effect on deep cutting ability, however shaving is very shallow cutting. You can get a very fine shaving finish on much thicker and more obtuse edges than on the SAK.

That being said, the thinner and more acute the edge, the worse it can be sharpened and still shave, and your SAK could definately use some metal hogging to get the cutting ability back given its wear.

If you can't get a fine edge on it, then simply back off on the grit and leave the edge very coarse. This will allow a higher level of edge retention with a degraded steel.

-Cliff
 
I also have a uarly '90's vintage Adventurer, and it doesn't hold and edge as well as my SAK Camper. My sharpening is done with a DMT tri-fold steel in fine grit. Even using a fine India Stone and honing oly,I can only get a mediocre edge. I really like the advent, it needs a saw, and a shorter pen blade too, but its a great tool.
 
Originally posted by matthew rapaport
I've also seen "professional sharpeners" ruin a knife by letting the edge get too hot on a hi-speed belt or wheel. Results in the effect cited above, a credible edge, but no edge retention to speak of. Otherwise, after years of sharpening, and without significant thinning, it might just be too thick behind the edge for you.
Click to expand...

Actually, that occurred to me as well. If somewhere along the line the temper was ruined, that'd explain things.
 
Many thanks to all who posted here. I'll try to respond a little to each post here.

Mr. Talmadge: yes I've pretty well done most everything you've suggested. Used the magic marker, generated the burr, light swipes on the finer stones, light stropping, etc. I've gotten it better, but still not what I would like to get it back to.

If something was done to the temper I'm pretty sure it wasn't doing the sharpening. It was done by a close friend of mine that is very, very weary of temper, and always has his water close at hand.
I've used it for quite a few years, around shops, welders, campfires, etc. Could be I did something really dumb with it that I've forgotten about, but for the life of me I can't remember.

Holy crap...I did just have a memory jog loose on me....no kiddin'...there was a time when I was using it on an electrical wall switch, and shorted it. The blade literally becoma a bit discolored, and I even lost a small chunk out of the blade. Could be onto something...that was around the last time I'd truly been satisfied with the edge...could very well be onto something there.

Ravenn: Gotta agree with ya', it's a great knife design, although you're right, it practically begs for a smaller blade and a saw. Thinkin' I'm gonna replace this one with that one handed Victorinox Military knife.

Mr. Stamp- 'preciate the input on that one. All else failing I think I'll do just what you suggested with this one, and use a coarser edge, better than nuthin' I reckon. Thanks for the suggestion.

Mr Rappaport: I like the thought of it being too thick behind the edge. I'm gonna take another look at it and see if that could be the case.

Mr. Clark- Thank you so much for sharing your experience with your own adventurer. I'm gonna try one more time with what you said, but nonetheless I like any suggestion that preserves my ego by suggesting a flaw in the materials.

I'll tinker with it some more this week and let y'all know how it came out. thanks again for all the suggestions!
 
Runs With Scissors

You have answered your question. The electrical short is your culprit. I have seen knives ruined more than once by electrical shorts.
 
Yup, I think you're probably right. What's wierd is how it just popped up at the very moment I was responding from the deep, dusty files of my feeble memory. maybe I'll just find a special place in my closet for it. I would frame it, but that would probably be one of those unusual decorations that makes everyone scratch thier heads an' look at ya' all funny like.
 
I see nothing wrong with framing it, it would make a great office decoration. In fact, you have given me some ideas.............
 
How long did you short the blade? A brief short would take bites out of the edge at the contact points, but I don't think that it would ruin the whole blade. If you are going to retire the knife anyway you might try some tests.

Get some 12 gauge solid core copper house wire and strip off the insulaton. Lay the wire on a 2x4 and using a hammer on the back side of the blade cut off pieces of wire with the edge. Try it on several places along the edge. Try and do it with one hammer tap per cut. See if the blade damage is very uneven.
 
Two thoughts:
Usually when someone burns a blade on something like a paper wheel they only burn the temper from a half to an inch of the edge, resulting in a flat (dull) spot on the edge

Electrical short burning a hole in an edge I have seen many of these over the years and I have always found them to HARDEN the area around the burn. Maybe grinding a new shape when removeing the hole after the short was where you (or someone) softened the blade.

Perhaps it is time to retire that knife and enjoy a new one

all the best, A. G.
 
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