Sharpening cheep blades

J

j.man

Joined
May 1, 2012
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I have been sharpening alot of my friends cheep 10-20 dollar knives to help improve my sharpening skill. After doing a few knives I have not been able to get the shaving sharp. They are just sharp enough to cut cumputer paper. Should I expect a sharper result with these cheap blades or is a sharper edge not possible.
 
You should be able to get a pretty good shaving edge on almost anything, actually. It likely won't HOLD on the cheap chinese steel, but the initial edge should be quite respectable. I see quite a lot of those, usually in an awful state of repair. Beware of the burrs, the soft steel seems to really hang onto it's burr in my experience. I typically end up resorting to a piece of pine end-grain to strip the wire edge before I strop on those.
 
Komitadjie said:
You should be able to get a pretty good shaving edge on almost anything, actually. It likely won't HOLD on the cheap chinese steel, but the initial edge should be quite respectable. I see quite a lot of those, usually in an awful state of repair. Beware of the burrs, the soft steel seems to really hang onto it's burr in my experience. I typically end up resorting to a piece of pine end-grain to strip the wire edge before I strop on those.
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Pretty much exactly what I was going to type. Thanks for saving me the trouble! :D:thumbup:
 
Have you tried marking the edge with sharpie so you can see were is hitting the stone?? You could be just missing the very edge. Also if you have an over angle stroke then you can ruin your edge and have to start over. This is assuming your freehand sharpening. Check out jdavis882 on youtube, he has some good videos on sharpening and a couple on 'why isn't my edge sharp'
 
I mark my blade with sharpie an I use a lanskey system so I know I am geting the right blade angle any sugestions on how I can make the blade sharper or do I just have to spend more time one it?
 
Light, light pressure as you get to the edge, make sure it is FULLY apexed on both sides, then take 'er to the strops and get rid of that wire edge. That might take a fair bit of work, they can be amazingly persistent. If it won't go away with stropping, then very, very lightly dragging the edge through the end grain of a piece of pine is a good way to strip the burr away. Then strop it again to put that final polish on it. :)
 
j.man said:
I mark my blade with sharpie an I use a lanskey system so I know I am geting the right blade angle any sugestions on how I can make the blade sharper or do I just have to spend more time one it?
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The Lansky clamp systems give you a consistent STROKE but a wildly inconsistent ANGLE, for a number of reasons. Just a heads-up.
 
Sorry to say, but if you can't get a cheap steel sharp you're doing something wrong, as they are the easiest to get an edge on (soft). Reevaluate what you're doing and re-do it.
 
Are you apexing the edge and forming a burr? If not keep working the coarse stone until you do. The trouble with the cheap (soft) steel is removing the burr. You could try the following:

Once you have a burr formed from each side, take a few light alternating edge-leading passes on the coarse stone to reduce the burr. Now go to the fine side and take a couple of edge-leading strokes in each direction, but with the angle increased significantly, and make these passes very light. This is to remove the burr from the coarse stone, and it actually forms a tiny microbevel. Now you need to return to the normal sharpening angle and back-sharpen on the fine stone to remove the little microbevel. Use light pressure and try to sneak up on the edge (i.e. don't oversharpen and create another burr). Finish on the fine stone with very light alternating edge-leading passes. You can repeat this process with an extra-fine stone if you have one.
 
Because the actual angle of approach is going to vary dependent on blade thickness and width, so the marked angles are nearly always false. Furthermore the stroke of the stones is nearly circular, which does not match the curvature of the knife edge precisely. This means that along the stroke the angle is going to be constantly shifting. It will allow you to repeat this stroke consistently, but the actual angle relative to the edge is going to be all over the map. So you DO end up with a sharp edge, but inconsistent edge angle. Likewise on large blades you have to keep shifting the clamp along the blade, and it will not clamp well to all types of knives. :)
 
Regarding marked angles on the Lansky in particular, they are only accurate as measured to the very front edge of the clamp itself. In other words, it's only accurate to those markings if the blade's edge is flush to the front of the clamp (which makes actually sharpening the blade impossible, in that position). I've used a Lansky for a long time without really being too concerned about the angle numbers. But, I finally became curious enough to take some measurements of the three sides of the 'right triangle' formed by the clamp/hone/rod/blade, then used a trig calculator to figure the actual angle. Any blade's edge which extends further out from the front edge of the clamp, will reduce the actual angle to something less than what's marked on the clamp.

An example, I use my Lansky to re-bevel a lot of traditional pocketknives, most of which have blades that are ~ 5/8" wide or narrower. I use the notch at the front edge of the clamp to hold these blades, so there's usually ~ 3/8" - 1/2" of blade extending beyond the clamp's front edge. Taking that measurement into account for the 'base' of the right triangle, the actual angle usually works out to ~ 14-15 degrees per side, when using the '17' marked setting. Wider blades will obviously reduce that angle measurement even more. The same discrepancies exist at the other marked settings (20/25/30) as well.

So, in a nutshell, any blade which is positioned in the Lansky clamp to allow the hones to actually contact the edge, will always result in an actual angle that's less than the marked setting would imply. For very wide blades, such as kitchen/chef's knives, the angle will be much, much more acute than the marked indicator, perhaps by ~ 4-5 degrees or more per side.

For small blades, such as found on pocketknives and most typical folders, the variation in angle along the edge's length isn't going to be significant enough to notice anyway. That 'arc' which the hone works in, won't make enough difference in the distance between the back of the clamp and the edge, to make a noticeable difference. With somewhat larger blades (> 4"), you might begin to notice some widening of the bevels, the further the clamp is from the ends of the blade. Even then, it doesn't mean the edge can't or won't be wicked sharp when you're done (assuming you've properly done your part). This is why I've never been too concerned about the actual angle measurement. It's basically a moot point for 99.99% of anything we will ever use our knives for. Sharpen the edge, use it, then go a 'little higher' in angle if the edge isn't durable enough for you. Or a little lower, if it doesn't slice quite finely enough for your tastes. Otherwise, it's all good.
 
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Personally I simply find the above to be an added irritation on top of the system being awkward and time-consuming to use (for me) as compared to free-handing. The system gives me no more accurate of an angle than I'm able to produce myself, and as such the length of time it takes to get it set up and use is much greater than simply busting out the unguided stones.
 
Would puting the knife in the clamp then setting the knife right side up then free handing with the stones work?
 
I have a set of precision metal files marketed for trimming and deburring small and delicate parts. I usually break out the flat file whenever my knife gets dull and needs touching up.
 
I make my own sharpner. if your knife steel is the one that is very hard then I think it is no good for you. I have sharpened the cheap china knifes,kershaw knifes,buck knifes and case knifes and have had no problem shaveing my arm after just to see if they are sharp enought.
 
Pretty much any metal can get a shaving edge. The difference between steels in this case is how that edge will hold up.
Most of the regular, non-knife-people I know who buy expensive knives do it because they think it will get them out of having to learn how to sharpen a knife.
They never believe me when I tell them otherwise, until they get to fondle a junk-cheap knife that I've sharpened.
 
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