Practical sharpening advice wanted

Joined
Sep 11, 2000
Messages
144
I'm new to sharpening, and am currently seeking to improve my technique with useful methods that I'm sure many of you currently use. What I'm NOT interested in are ways to get my knife "so heinously sharp that it'll cut your eyes when you look at it". I'm sharpening my knife to use it, not display its push-cutting abilities in the Smithsonian.

With that said, I tend to use a knife for general tasks, and sometimes whittling when I go for walks in the desert. Sometimes I cut rope, or food, or maybe a tag from a T-shirt. So mostly it's slicing I want to improve, not push-cutting.

I have a Sharpmaker 204, and while it's very nice, it also seems to be a bit imprecise. What I need are ways to tell how well I'm doing as I go along. Here's what I do so far, taken from tonight's sharpening chores:

1. The knife in question is chisel ground, sheepsfoot blade, 1/8" think at the spine, but only 2.8" long. It's thick and fat.
It's double-beveled, with 20 degrees on the secondary bevel, put there by my Sharpmaker.

2. When I finish on the smooth stones, I wonder to myself if my knife is really sharp. It will drag on my fingernail at fairly acute angles, but it doesn't shave very well at all. Which isn't so bad. But how usefully sharp is it?

3. One test I use is to run my fingernail over the edge, like a hard little snail. What I found tonight is that after using the Sharpmaker, there is a series burr on the left side. After taking the burr away, I alternate sides, but then the burr is back! Also, the worn-off steel on the two ceramic sticks has very different patterns. On the right stick, the steel is evenly placed. But on the left stick, there is a band that never gets any steel on it, no matter what I do. I tried to see whether the stick was curved, but it didn't seem so. Hmmm. What could be causing that?

4. So I take the burr away again, and try different pressures, favoring the left side. That helps, but there's still a bit of a burr. It's a testy blade. But finally I get the burr to go away.

I can only assume at this point that the angles on the blade are equal; and since there is no burr, it should be soul of sharpness, right?

6. The next step is to shine a flashlight directly on the edge. On most of the blade, I cannot see any edge. As I turn the blade under the light, there is no division between the left and right sides, whatsoever. I just can't see it. I assume this is a good thing. There are two places that have very tiny nicks, and these shine. The nicks are not discernible when looking from the side, though.

7. I strop it a bit on some denim, just for good measure, in the hopes of straightening the micro-serrations. I don't want them to go away, I just want them aligned. I assume this won't hurt slicing performance too much, since it's not really a "polished" edge.

8. At this point, I'm still wondering, is my knife sharp? It will slice paper with no problem, but it certainly doesn't grab any hairs. It can't shave the hair on my thigh, but if I scrape, it will shave hair from my arm. Since I didn't polish the edge, that doesn't worry me greatly, but I did think it would be at least sharp enough to shave more easily.

My question is: What practical techniques can I use in this process to gauge my progress more accurately, such that I can apply the necessary adjustments to ensure a successful end? I probably abraded way more steel than I needed to, since it was sharp this morning, and all I did was whittle a desert stick to nothing. After that, it wouldn't drag on my nail anymore, and I forgot to try steeling before sharpening. But in the course of sharpening, I decided I wanted an edge that I could know was sharp -- yet now I'm wondering if this might not be a nebulous thing indeed!

I suppose in the very olden days, someone who was expert at sharpening would have watched over my shoulder, righted all my wrongs, and given me tips exactly when I needed them. But this is 21st century. No one I know is a master at very much, and when you want to learn something well, all you can depend on is a manual, your modem, and the friendly people from the Internet.

Any masters out there who can impart their wisdom-at-a-distance?
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Welcome to BladeForums!

You'll find that there is a great bunch of folks here that will always be willing to offer help.

Joe Talmadge's sharpening FAQ here is a great resource, as well as John Juranitch's The Razor Edge Book of Sharpening. I highly recommend both!

You seemed to be off to a good start. It sounds as if we both use our knives for similar purposes, so maybe a few things I've learned can help.

In your #3 step, I suspect you may be putting too much pressure on the blade, or simply too many strokes, and that is bringing the burr back. Remember, once you get a burr, it only takes a stroke or two to remove it, and another stroke or two to raise it again.

Personally, I wouldn't be too concerned about the pattern of metal on the stones - the stone may just be slightly imperfect. It won't take much to show up like what your describing. Luckily, differences as small as that won't have much impact on the edge you can get. Heck, mine have never had the same pattern on both stones and I do get a hair-popping edge.

Steeling is great for maintaining an edge, but once the edge is dull enough to need sharpening, steeling before sharpening doesn't really accomplish anything. Steeling should be done after sharpening (with very, very slight pressure), and in between to maintain the edge.

In regards to precision with the 204, it's a simple matter of locking your elbow and wrist so that all of the turning is in your shoulder. This will greatly improve your control. After you get comfortable doing this, you can then start turning your wrist so that the edge of the blade in contact with the stone is ALWAYS perpendicular. If the stone isn't, you will very slowly reshape the blade and end up with a bevel that narrows as you get closer to the tip.

To get that hair-popping edge, I use the flats of the white stones only and alternate each stroke. The real key is, once you get the edge to where you have it now, greatly reduce the pressure. I'll usually do about 4-6 strokes each side with just the weight of the knife. Then, about the same number with just enough pressure to keep the blade on the stone. I'd guess that it's less than 1-2 oz. It's that very light touch that will get that last bit of sharpening the 204 can give you. After that, it should take care of hairs easily. Stropping can then take it further, but I usually don't go that far.

Nebulous, huh? Well, I must be nebular myself because I love that extra sharpness. Unless you're digging into something rough that could possibly chip the blade, I think that extra bit makes a BIG difference in ease of cutting.

I hope these suggestions can help you.

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Knowledge without understanding is knowledge wasted.
Understanding without knowledge is a rare gift - but not an impossibility.
For the impossible is always possible through faith. - Bathroom graffiti, gas station, Grey, TN, Dec, 1988


AKTI Member #A000831

[This message has been edited by Codeman (edited 09-22-2000).]
 
I'm pretty sure I'm not a master, but here's my shot about the burr that won't go away
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I have several knives that do exactly that. My take on this is that some steels are relatively softer, so when you get the edge too thin (very sharp), the pressure you apply on the stone will just move the burr from one side to the other. More than often it was when I sharpened stainless steel blades. At this point I will use my coarser stone to get rid of the burr and leave a coarser finish (good for user knives); or I may follow with a few swipes on the fine stones with less pressure.

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Reynaert
 
JohnW,

If you are having "problems" with using your Sharpmaker 204, I have a Lansky 4-hone Diamond Kit (also includes 3 "extra" stone hones, and some other "extras") that I'd trade with you.
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Let me know...

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

Let's try it this way. Shaving hair is a push-cutting edge feature, not a slicing edge feature. However, since shaving hair provides an easy test to show that your basic sharpening skills are sound, let's first try helping you get a knife that's shaving sharp. Once you get there, we'll know your sharpening skills are sound, and we can recommend what to change in order to get a slicing edge.

Step 1: Raise a burr

Set up your sharpener with the coarse sticks. I use a circular motion on the sticks, being careful not to let the tip slip off (this will round the tip). Sharpen one side only until a burr is felt along the entire edge length of the other side. This means you've gotten the edge bevel all the way to the very bleeding edge tip. Now switch sides and repeat sharpening that one side only until the burr has flopped completely over to the other side.

Step 2: Grind the burr off

Okay, from now on, you'll always switch sides between strokes. Do a few more strokes on the coarse stones, then switch to the white fine stones. Work the white stones until all the scratches from the coarse stones are gone. Once you get close to that point, start letting up on the pressure that you use to drive the knife down the stone. You'll use a lighter and lighter touch until the blade is only going down the stone drive by its own weight and not you pushing. This lightening phase ensures that the burr gets smaller instead of bigger.

Step 3: Finish the burr off completely

If you don't have a proper strop and paste, some people have said they've had good luck using coarse cardboard, like the back of a notepad. Strop the blade for a little while, using an easy touch. This should break off any remaining burr.

Step 4: Really finish off the burr

Hopefully, step 3 removed your burr completely. If you still think you have one, try this. With the white stones in the Sharpmaker, instead of holding your blade perfectly vertical, tilt the blade's spine in towards the center a tiny bit. You're trying to increase the angle between the edge and stone by a degree or two. Now, let the blade run down the stone with only the weight of the blade driving it down. Switch sides, repeat, then do the whole process again. This is called double-grinding, and should definitely remove your burr completely. Strop lightly again if you want.


At this point, your knife should shave hair easily. Good! Now that you're confident of your sharpening skills, we can change your blade from the great push-cutter it is now, to a great slicer.

To do that, we want to rough the blade back up. Put the coarse stones back in. Switching sides between strokes, you'll again let the blade go down the stones with only the weight of the blade itself driving it downwards. Maybe a touch more pressure at first, but then lighten up. This will rough up your edge. It should still shave hair, but not as good as it used to. But it will kick butt on slicing.

For my slicing tests, I use 1" hard poly rope. I try to do one hard slice before I sharpen, to see how the knife is performing. I do it again after I sharpen, and expect to see a huge increase -- like several hundred percent -- after I sharpen. A dull or razor-polished edge will barely cut into hard poly rope. A good coarse-ground edge should get halfway through (and preferably 3/4 through, or more) with one slice.

Joe
 
I'm far from a master, plus Joe and Codeman already covered sharpening techniques on the Sharpmaker. Just wanted to say that if you're getting a good edge and losing it quickly (whittling one stick) the problem may be the knife. You didn't name a brand or steel. On the other hand it may be your sharpening. You may be getting a "wire edge" that indeed feels sharp, but is also gone the first time you use the knife.

btw, it took sharpening several knives on the Sharpmaker for me to really get it right.
 
These are some very good points. Let me add a bit more information, since you've all led me to thinking further.

The blade is 440C hardened stainless, a Myerchin knife. Since I couldn't find a buyer on the "For Sale" forum, I figured I would use it as a general whittling/utility blade on my hikes.

I never used to check for a burr with my fingernail until last night. When I found the burr, I thought it would be very easy to take off. I was totally wrong about that. At first I just touched up the blade on the stone, expecting the burr to go away. But it was still there. So I did it some more. Finally, I got so frustrated with this persistent burr, that I really grinded away on the white stone with just that side. STILL the burr was there! It took a lot of work to get that burr off.

My only guess is that in past sharpening attempts, I was building up a major burr that I wasn't aware of. Is this possible? Anyway, after fifteen heavy strokes, the burr finally went away, and moved to the other side. By then the burr was very weak, and could be moved over with very little pressure.

BTW- Lightening up on the pressure as I get toward the end I haven't tried. I'll do that next. Thanks!
 
John,

Lightening up helps keep the burr small, but stropping or double-grinding is what really gets rid of it completely, on blades that have troublesome burrs. I prefer double-grinding, I feel like it works by grinding the burr off and leaving the edge still sharp, instead of rubbing it off like a strop. But double-grinding takes a touch more skill, whereas getting good results on a strop seems like a no-brainer.

Joe
 
Everybody's comments really paid off. Here is the latest news:

I took my knife from last night out to the desert again, and whittled a small 1x2" board into a little wooden knife. Lots of shavings this time.

Predictably, it wouldn't shave hair very well, but it could still scrape hair. I guess 440C isn't that soft.
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So instead of grinding away, I tried the "lightening up" technique, of using lighter and lighter alternating strokes. This got it back to decent shaving ability after just ten strokes total.

Feeling with my fingernail, there was a very small burr at the edge. With just the lightest possible stroke, it moved to the other side. I could make it jump side to side with almost no pressure on the white Sharpmaker stones.

So I tried Jeff's "double grind" technique of using a fairly oblique angle (30% bevel), but with incredibly light pressure (much less than the weight of the knife), and only one or two touches per side. He suggested this in lieu of rubbing off the burr by stropping.

This both caused the burr to disappear, and has achieved a level of shaving sharpness I'd never attained before. And with a slightly strong edge to boot, given that there are now three bevels leading to the point!

I finished up by steeling on my marlingspike, and stropping on denim for good measure.

The only thing I need to know now is: Where do you guys get more arm hair from? I wonder if DiscountKnives has a Rogaine section..
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I always do the last "stroke" with "NO" pressure at all (just "barely touching") ALONG the edge on the white stone.
This takes any "residual burr" away.
Then: it CUTS!
Happy sharpening: Ted
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D.T. UTZINGER
 
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