Uneven sharpness

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Brutus013

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On my Sharpmaker, I've noticed that on some knives, one side will be "sharper" than the other. What I mean by this is that it will shave hair, for instance, only when the blade has one side towards the skin. If you flip the blade over so that the other side of the blade is towards the skin, it no longer shaves.

I'm assuming this means I'm either using unequal pressure when sharpening, or I'm not holding the knife straight as I sharpen. How can I tell which way I'm angling the blade or which side I'm applying more pressure to? I can't tell by sight or by touch.
 
That is happening because of a burr, use light strokes and finish with a strop.
 
Drag you thumbnail across first one side, then the other. Your nail will catch or scrape on the side that has the burr.
 
Generally the side that shaves (assuming the other side won't) has the burr.

Mike
 
Thanks.

As a temporary solution (I have no strop), a few strokes per side at the 40 degree setting (I usually sharpen at the 30 degree) gets rid of the burr well enough.
 
Certainly a burr, as others have said. With some steels they can be very stubborn, even very light pressure with the Sharpmaker just sort of flops it over from one side to the other.

Remember that to get a really durable edge, you not only have to remove the burr but also the steel immediately behind it which has been weakened. The best way of doing this that I know of is Jeff Clark's trick of making a few very light passes on the Sharpmaker at a much elevated angle - like 40 degrees per side. At first I was very skeptical of this method and thought it would destroy all the hard work put in raising the edge in the first place. But not so. With a microscope I looked at burrs and edges doing this, and found that doing 4-5 light passes on edge side, alternating back and forth of course, is usually all it takes. After that it takes very little work, again only a few swipes on the Sharpmaker at the desired final angle, to raise a really good, clean edge.
 
With a SM and a bit of practice, you should be able to get a shaving sharp edge [I]without EVER raising a burr![/I] :thumbup::p
 
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An EASY way to see if there's a burr on your edge:

I've noticed when I strop my blade, if there's even a hint of a burr on either side of the edge, the burr acts like a 'hook' (think of the blade's cross-section) and will scrape & collect little bits of leather and/or compound (if you use compound on your strop) on the burr side. This makes it obvious if there's a burr and what side it's on.

When I notice this, I use a Spyderco Double Stuff ceramic stone to 'strop' the burr out of the edge. In other words, I place the burr side of the edge on the stone, and VERY LIGHTLY draw the edge in a TRAILING motion (AWAY from the edge, SPINE FIRST) down the stone, just as you would on a strop. As is always proper when stropping, make sure that you keep the angle of blade vs stone at the lowest possible angle, so you won't end up 'rounding' your edge. Make 3 - 5 strokes this way, then strop on leather again. If there's still any burr left, it'll collect little bits of leather and/or compound as before. But, hopefully it'll be less this time. Keep at it in this manner, until you're no longer seeing any leather or compound on either side of the edge. Then you'll know the burr is gone.
 
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