What am I doing wrong sharpening

T

texasrimfirenut

Joined
Oct 13, 2013
Messages
168
Hey new to sharpening on regular stones. When I sharpen, the knife will get shaving sharp but I've noticed while feeling the edge of the knives, one side seems to feel sharper than the other side.

Is this normal or am I making a mechanical mistake?

Should me strokes have good pressure down on the blade or should it be light?

Thanks for any help/instruction.
 
Can you elaborate about what you mean when you say one side feels sharper? A sharp knife should be perfectly apexed, so both sides of the blade should feel smooth, so if you pinch the blade and slide towards the edge, you shouldn't feel anything. You should not feel a burr on either side.
 
texasrimfirenut said:
Hey new to sharpening on regular stones. When I sharpen, the knife will get shaving sharp but I've noticed while feeling the edge of the knives, one side seems to feel sharper than the other side.

Is this normal or am I making a mechanical mistake?

Should me strokes have good pressure down on the blade or should it be light?

Thanks for any help/instruction.
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That's likely a burr that's folded or leaning to one side; that's exactly how it'll feel. Good news is, you're on the right track. Creating a burr is the best & most reliable way to make sure the bevel on each side has been ground flatly & fully, until the steel thins enough at the edge to fold over toward the other side. At that point, you're halfway there. Make sure to create & verify this burr from BOTH sides, so you'll know that each bevel is flatly and crisply intersecting at the apex of the edge. This means when you notice the 'sharpness' of the burr from one side, you need to work the other side (toward which the first burr leans) and make the burr 'flip' in the other direction, so you're feeling it from the other side. When you've flipped the burr like this, and verified you can feel it along the full length of the cutting edge, then strop the edge to clean up the burr. The goal of stropping is to gently and carefully remove the burr, either by bending/folding it in both directions until it breaks away, or by gently abrading it off. Depending on the steel's ductility, the latter is usually the best way to do it (abrading/filing it off). More ductile steels will be stubborn about not allowing the burr to break off, and it may bend back/forth forever. Gently filing it down, either with a strop using compound, or on a stone (finer grit) is generally the best way to clean it up.


David
 
I get a burr every time I sharpen and I use it to gauge which side needs more work than the other. Slide your thumb perpendicular to the edge on both sides, if you have a burr then one side you should feel your thumb slide right off while the other sort of grabs your thumb and this is a burr. To get rid of the burr I like to sharpen the side that has the burr using very light strokes where the only downward pressure is the weight of the blade itself. Use the same angle you used to sharpen before or VERY slightly raised to help knock off that burr.
 
Thanks guys that is making sense now. I mean the thing will shave pretty good but you have described it well. When I run my finger across the blade one side will feel almost smooth and when I pull my finger across from the opposite direction it will really grab my finger. Sounds very much like the burr you guys are talking about.

I can hit the stone with just a few strokes and it will change this reversing the direction I am feeling the grabbing of the knife.

Ok so I just need to strop now.

Hate to keep asking but want to verify: This is a non-convex edge knife and the videos I have seen on stropping have been for convex so two questions.

1. When stropping a non-convex edge knife do I hold it at the same angle I sharpened it on the stones?
2. How much pressure do I put on the knife as I am stropping it?

Thanks guys you all are such a big help and I have improved greatly with knives/sharpening since joining this forum. Spent a lot of time frustrated before joining the forum and spent years in "given up" mode being at the mercy of family members to sharpen my knives whenever the felt like - meaning I almost always had dull knives which led to not much interest in owning them. This forum has made a huge difference and its guys like you all that make it such a great place.
 
For stropping you will use the same angle with only the weight of the knife on the strop. Use too much and you will round the edge :) Be careful not to over strop
 
texasrimfirenut said:
Thanks guys that is making sense now. I mean the thing will shave pretty good but you have described it well. When I run my finger across the blade one side will feel almost smooth and when I pull my finger across from the opposite direction it will really grab my finger. Sounds very much like the burr you guys are talking about.

I can hit the stone with just a few strokes and it will change this reversing the direction I am feeling the grabbing of the knife.

Ok so I just need to strop now.

Hate to keep asking but want to verify: This is a non-convex edge knife and the videos I have seen on stropping have been for convex so two questions.

1. When stropping a non-convex edge knife do I hold it at the same angle I sharpened it on the stones?
Click to expand...

Generally, keep the angle conservatively low. If there's any 'give' or conformability to the strop, as with softish and/or thick leather, you'll still likely make some contact with the edge at an angle that's actually lower than the sharpened angle, because the leather will be wrapping around the bevel and apex somewhat. You don't want to go too high in angle, because that'll compound the rounding effect on the softish leather.

2. How much pressure do I put on the knife as I am stropping it?
Click to expand...

As little as possible, again to avoid or minimize the compression of the leather underneath the edge bevel & apex. To sum up, low angle and low pressure is always best on a strop that is somewhat soft or compressible underneath the blade. Hard or firmly-backed stropping surfaces, such as wood or thin paper over wood or glass/stone, are much more tolerant of pressure, so long as the bevel is maintained flush to the stropping surface. This applies to any edge, convex or V-bevel. With some practice, you'll develop some feel in your fingertips for flush contact while just 'kissing' the apex itself, and it'll be much easier to regulate both angle and pressure.


David
 
Thanks guys am building some strops now and have tired this already with just leather setting on my table.

Got 1/4" cowhide leather gluing to 1/2" thick board which measures 3"(w)X8"(l).

Have ordered green and red compounds to put on them. Right now I have no compound I am using. Bought some at Sears but it wasn't green when I pulled it out and no where could I find nor did Sears know what micron it was. Decided to order some in that I knew for sure what I was getting.

I also ordered the Fallkniven DC4 stone and picked up some 2000 grit sandpaper for the F1 that will be here in a couple days. From what I understand, probably all I will need is the leather strop and chromium oxide to keep it polished up after use unless there is some extra heavy action use with it.

Really again, I can't thank everyone enough for all the help and the good attitudes of forum members. Most of you long timers around here probably don't even realize how helpful everyone is here because it has become what you are used to ... but for us new folks who come here ignorant and wanting to learn - this place and all you members are totally awesome!
 
^^ You might find the red compound (iron oxide) to be ineffective on your edges. It's generally intended for softer metals, as used for jewelry & such, and often won't be hard enough to polish or abrade hardened steel. The green, white and black compounds are much more useful for knives, in most mainstream steels. Very high-wear steels that are heavy in vanadium carbides, like S30V, S90V, etc., benefit more from diamond or cubic boron nitride (CBN) compounds, which are hard enough to refine the extremely hard vanadium carbides in those steels.


David
 
You are pressing down harder on one side than the other I still do my self at times I use a forty year old case butcher steel to clean it up
 
Obsessed with Edges said:
^^ You might find the red compound (iron oxide) to be ineffective on your edges. It's generally intended for softer metals, as used for jewelry & such, and often won't be hard enough to polish or abrade hardened steel. The green, white and black compounds are much more useful for knives, in most mainstream steels. Very high-wear steels that are heavy in vanadium carbides, like S30V, S90V, etc., benefit more from diamond or cubic boron nitride (CBN) compounds, which are hard enough to refine the extremely hard vanadium carbides in those steels.


David
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Ok, great and thanks for letting me know. So I guess the green is good enough or do I need another color/grit as well?
 
texasrimfirenut said:
Ok, great and thanks for letting me know. So I guess the green is good enough or do I need another color/grit as well?
Click to expand...

Yup I can see that as well since I am naturally better controlling the stroke toward me than I am when turning the blade the other direction and pushing it away from me. Makes sense. I was paying close attention to making sure I was holding the angle correctly on each direction and never thought about making sure I had the same pressure both ways. Thanks for the heads up on that. I'll keep an eye out for it.
 
texasrimfirenut said:
Yup I can see that as well since I am naturally better controlling the stroke toward me than I am when turning the blade the other direction and pushing it away from me. Makes sense. I was paying close attention to making sure I was holding the angle correctly on each direction and never thought about making sure I had the same pressure both ways. Thanks for the heads up on that. I'll keep an eye out for it.
Click to expand...

oops meant that reply to be attached to buckeyes quote.
 
texasrimfirenut said:
Ok, great and thanks for letting me know. So I guess the green is good enough or do I need another color/grit as well?
Click to expand...

Green is usually good or even great as a maintenance/touch-up compound. If you have heavy burrs off the stones, the black and/or white compounds will clean those up quicker. These three are often used in sequence, as in Black -> White -> Green. Depending on what edge finish you like, and maybe on the steel also, you could be happy using any one alone, or any combination of those. If you want to start out with the green for now, that's fine. It'll take some time to get a feel for how it's working for you, and I'd encourage you to experiment with as many as you can afford, and keeping an open mind (always) about them. These are things you might come back to later, as you gain experience, and your opinion may change about them over time. Early on, when first trying to learn it all, it's easy to write off some methods or tools that seemingly don't work, but magically start working later on, after one's hands are 'trained' to it all. ;)


David
 
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