Raising that burr faster

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DocNightfall

Joined
Nov 20, 2006
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268
I've found (thanks to this forum) that one relatively foolproof way to get a good edge is to raise a wire edge then break it off by stropping. I have been experimenting with sharpening with the edge trailing instead of the usual way, and I've found that I am able to get that wire edge faster with this method, and achieve the same results after breaking it off.

Why do nearly all people sharpen with the edge leading if it is easier to do it the other way? Am I ruining my knives?
 
Well, really what ever works for you. In general (but I am sure that is only terminology) you don't want to break of the burr, but rather abrade it gently. If you break it of, it usually leaves a ragged edge. On some steel, just stropping isn't going to remove the burr. Burrs can be very stubborn at times. So many prefer NOT to raise any burr, or only as small a burr as possible so that they don't have to fight it afterwards. Again in general, it is really not wise to raise the burr, just because, or to use a technique that raises a burr as quickly or as large as possible. The whole thing about raising a burr is more for the beginner as a sure way of telling when the bevel that you are working on truely reaches all the way to the edge. Actually, I really doubt that you are raising a burr faster. In order to raise a burr you have to remove the same amount of material no matter whether you work edge trailing or edge leading. I assume you simple feel the burr earlier because the burr is usually larger with edge trailing.

But again, use what ever works best for you. If you get a good edge, you are certainly not ruining your knives. Personally I have had better experiences with edge trailing on soft abrasives, I assume because it is very easy to "plow" the edge into the abrasive. On hard abrasives I found edge leading strokes more efficient, again probably because you generate more friction at the edge.
 
I have a book writen about how to srarpen knives, and the writer talks about useing a steel to align the edges, and to use it with a dragging cut as you talk about, and not a cutting movement...

Dragging does not cut into the steel with the edge, and the thinking was that dragging was better for the final result.

You seem to be dragging too, and I guess this could help as well with the final result.
When I first sharpen a knife for it's first time, I work the 1st edge in both directions, cutting into the stone and dragging back...

It is my view that the wire is very important,
and you must get a wire or you are never sure if the blade has been sharpened as much as it could be.
When I get a wire working one side of the blade, I know I can then flip the blade over and do the 2nd side, because the wire tells me that the 1st side is as sharp as it's going to get.

Now if the knife has been sharpened many times before, and does not have any little nicks, then you dont need to go for the wire every time...
But if the knife is very dull, or is new, or has been nicked, then getting the wire is where you have to aim for first
 
If your aim is to get a burr, it doesn't really matter which direction you sharpen. As you say, edge trailing may be better. The real trick is removing the burr. I'm not convinced stropping is a great way of doing it, as the strop is usually a compliant medium with very fine abrasive quality. Either the burr breaks off, leaving a dull edge, or the burr is simply deformed into something of a wire edge, prone to rolling.

As far as raising a burr quickly, I find using a very hard, long wearing abrasive, such as ceramic, in an aggressive manner will raise a burr quite easily. Not that I always find this a good quality.
 
Often stropping or steeling doesn't remove a wire edge, it primarily just lines it up so that you can cut with it. On soft material like meat or for some incidental shaving this straightened wire edge may work very well. On tougher material the edge may break down unusually fast.

For rough sharpening or reprofiling I use any old stroke that works. I often use back-and-forth strokes until I get tired and then circular strokes for variety. I don't particularly try and form a burr unless I am in a hurry or frustrated. If I do form a burr I remove it as soon as possible using very light edge-forwards strokes at an elevated angle. When I really put on the edge I try and avoid creating a burr. This is why I use edge-forwards strokes for actual edge honing. The burr is formed by metal that bends away from the hone rather than being cut by the hone. Edge-forwards strokes slightly catch the material at the edge and cuts it off more efficiently.
 
I used to raise a burr every time I sharpened on a benchstone, but for the last year or two I've been trying to avoid it. I realized that I was spending more time and effort trying to remove the burr cleanly than I spent creating it in the first place. It takes some experience, but after awhile you can tell when the bevels are about to meet, so you can ease up and start alternating sides. It's hard (or maybe even impossible) to entirely prevent a burr from forming, but I think you get a better edge if you can at least minimize it.

When I do any kind of aggressive reprofiling on a benchstone, I'll go back and forth (pushing with the edge forward and pulling with the edge trailing) at a pretty high rate of speed. Some people prefer to go in circles, but it's hard for me to hold an angle when doing that. I agree with Mr. Clark that push-strokes are best when putting on the final edge or removing a burr. Diagonal strokes (pushing forward and moving the blade to the side at the same time) seem to work well too, especially for removing a burr.
 
Gee Cerulean, you just gave me a new concept in burr removal, intentionally honing on a diagonal line. I've been consciously fussing with burrs for about about 40 years and never considered that--doh! Of course it is hard to prevent some diagonal action during honing, but I haven't been conciously controlling it with respect to handling burrs.

Of course you could have the idea backwards. Maybe we should be minimizing transverse motion in order to cut off the burr optimally. This really begs for a controlled experiment. I shall have to think about it and find some time.
 
Very informative, guys. I've harvested some great info from the guru's here and here is another example - thanks guys!

Seems to me I've seen the woodworking sharpening guru's take off the burrs with a sideways (same direction as the edge) stroke at a slightly higher angle. I'm pretty sure the the shapton site is where I saw this.

Getting a loupe helped me a lot. I can feel burrs, but it really hits home when you look at it, and often you'll get a nice burr on a portion of the blade before you are even to the edge on other sections of the blade. Getting a loupe really helped me to make sure I got my sharpening done along the entire blade, and can help you get to where you will hardly raise a burr.
 
For me, the quickest and surest way to remove a burr is to elevate the blade by 3 to 5 degrees and hone forward. This puts pressure at the base of the burr/foil, cutting it off even if the burr bends away from the stone. I usually use a finer hone (either side of a Spyderco DoubleStuff). The result is not only removal of the burr, but also a finished micro-beveled edge.

I use a strop only to produce a fine polished edge. Those times I've tried to remove a burr by stropping only resulted in a sharpened burr or incomplete burr removal. This can be a real problem for beginning hand-honers, since the knife seems extremely sharp when slicing newsprint with a sharpened burr/foil, but the edge is useless for cutting any substantial material.

I've found a loaded strop very useful for detecting remaining burr (or any other edge defects), since edge imperfections 'print' on the loaded strop. You'll see the 'tracks' produced by edge imperfections as the edge is trailed across the stropping compound. If the surface isn't shiny, you're not done.

It's also a good idea to make a few full-edge slices into a material (pine or harder) as a final test for any remaining burr, followed by a draw cut through newsprint to see if the slicing rolled or tore off any remaining burr.

Hope this helps!
 
I always take diagonal strokes for burr removal and in the final steps. The idea came simply from working with wood. If you want to sand a wooden wedge to a very acute edge and remove the very visible fuzz at the edge you automatically, with out much thinking, tend to take a stroke which is mostly in line with the edge. You would also tend to use mostly a trailing stroke which is partly due to the fibrous nature of the wood though. I find shapening a wooden wedge on simple sandpaper to, let's say, 12-15 deg can teach you a lot about what is going on when you sharpen.
 
Forming a burr and then having to remove it is a waste of perfectly good steel and time. I never form a bur, always slice into the edge as this helps avoid forming a bur. Use light strokes when you start to get close ( the weight of the blade only). Do not strop to much, as that will form a very small bur that you may not notice. As mentioned above a micro bur will layover or break off dulling the edge quickly.Ocassionlly in crease the angle by about 5 degress for one or two passes. For the final I like to strop and then go back to the 1200 Grit DMT for afew strokes and then strop a few more strokes. This system provides for a very sharp edge that holds very well.

Leon Pugh
 
Hob is right that you can learn a lot about burrs by sanding wood. I first noticed burrs when I was in elementary school. Some friends and I were playing around making arrowheads by rubbing shards of terra cotta flower pots on cement. These would form rather clean edges with no burr. I branched out and sharpened some Popsicle sticks by similar rubbing on cement. While this worked it tended to leave a really conspicuous burr of feathery wood. This was reduced if I whittled the point before I started honing. The problem was that if I removed too much material by honing I was left with this residual burr. This burr was very hard to remove by honing on cement. I didn't understand the relevance to knife sharpening steel at the time.
 
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