How do you break an unbreakable burr

M

maximus83

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Nov 7, 2011
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I've got an issue on a large carbon steel thick bladed knife. It has a really tough burr and even after multiple high-angle slices, even de-stressing the edge, I cannot seem to get rid of that burr.

Suggestions on this? I'm frustrated enough I'm about ready to take a bastard file to that bastard. :)
 
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OK, will try that tomorrow. One thing that's weird: with this knife, I did try really consciously while profiling to only do minimal scrubbing, then flip sides. It just seems like it forms stubborn burrs really easily. It is a cheap Schrade, so there's that, I don't know if the quality of the steel has a lot to do with it.
 
Don't throw it down and walk away cussing!
When I saw the title I figured it would be on a thick bladed carbon steel blade. I get the same on my axes and they are hard to get off. I think it's a combination of a thick edge and the steel. 1) I flop it back and forth on a India oiled stone maybe 3-4 times. Attempting to reduce it as much as I can. Even lift the spine and do a pass across the stone. Not length way. 2)Then I take it to a medium hard leather loaded strop. And give it 2-3 light stropping passes on it on both sides. Lifting the spine as much as I dare. Maybe a couple of times. And its well reduced or gone. 3)
If it still persists take it to a denim strop or double layer of blue jeans and high angle strop it 2-3 passes and check the edge. DM
 
I think in your attempt to remove the burr you’re succeeding and then creating a new one. A cheap carbon steel blade should not give you trouble with a burr like that.
Strop the blade on a fine or medium grit stone. Thats usually works for me.
 
Extremely light pressure edge leading at high angle with the finest diamond stone you have. Use about double the angles. Don’t press till it flip, let the stone abrade it slowly. Check often, be careful when it’s almost gone, do alternating side pass at the original angle.
 
I always strop on a leather strop or a balsa wood strop. I always liked the results better than stropping on a stone.
 
Keep the angle flush to the bevel, reduce pressure (probably by a lot) and thin the burr to hone most of it's thickness away. Burrs that are too stiff to break away are too thick. That happens when pressure is too heavy laterally against the edge, causing the burr to roll over before it's thin enough to break away on it's own. Increasing the angle to try to break it away will also magnify that pressure; if done too soon before it's adequately thinned, it'll potentially be more difficult to remove.

Edited to add:
The Goal: the burr should be thin enough, that it'll strip or break away with little effort, such as by stropping on some denim (your jeans) or even cutting into the edge of a sheet of paper. It may also come off on your fingertip in feeling for the burr, if it's adequately thinned. If it's still too tenacious to come off, that's a sign some more thinning and reduction of pressure is called for. Even more so, if it's also resistant to being 'flipped' from one side to the other.

The pics below are of a burr I formed on a Victorinox paring knife's edge, using a ceramic stone (Spyderco medium). The burr started to tear away when I stropped the edge on a leather strop with some green compound. You can see a bit of the green compound and/or leather near the edge in the 3rd pic, BTW. I tore off the remaining bits of the burr by drawing the edge across a piece of wood, in that example. By naked eye, that burr just looked like a very fine piece of lint fiber dangling from the edge (I thought it was, at first).

kxNPzMN.jpg

B047BIR.jpg

mIacPbu.jpg



David
 
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When Dad taught me how to sharpen knives growing up, it was on a medium/fine whet rock.
The only time we used the fine side was for removing the burr.
*Disclaimer - Good, bad, or indifferent, your results may vary. :)
Have a great honing day!
 
Wonderful photography Obsession! One needs extra arms to get stuff like that recorded for us. Thanks !

Joe
 
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