sharpening with sharpmaker and lee valley strop/compound

[bigbcustom]

I just thought I would post about my experience with the sharpmaker including diamond and ultrafine stones plus finishing on the lee valley wood backed leather strop with the lee valley blade honing compound. I went through these steps with the benchmade fecus gamer, and the spyderco delica. Gamer has 440c steel, delica is aus-6...not the super steels but good servicable blade steels. First I profiled both blades to a 30 degree included angle with the diamond stones. This was relatively fast due to both these knives having a factory bevel close to this. Then I proceeded through the grits on the sharpmaker examining the edge with a lighted 15x loupe (I feel this loupe examination is important to make sure: 1)you have truly gotten the whole bevel to your intended angle, and 2)you have removed all the scratchmarks from the previous grit.) Some guys say you don't need to remove all the scratchmarks from the previous grit, but I did it anyway to get a true feeling for the best edge obtainable from this set up. It was fast from the diamond through the grey/brown medium grit stones. Going from the medium to the fine white ceramic took about 120 strokes each blade to remove the medium grit scratch marks before turning the stones to the flats, going to the ultra fine white ceramics took very little time to refine the scratch pattern (remove all the previous grit scratch marks). I don't know whether this means there isn't much difference in grit or if the ultrafine sticks were cleaner somehow. ***interesting note here, the ultrafine sticks were easier to feel the cutting action on even though they left finer scratch marks than the fine*** any opinions on why this is? I then made a slurry with the .5micron lee valley blade honing compound and applied it to the wood backed leather strop rubbing it in with my thumbs for about ten minutes (ya I know this is a long time, but I wanted as near perfect an application as possible...when I was done, I could have used my thumbs as strops lol they had as much compound imbeded in them as the strop lol) I then stropped in the accepted manner (trailing of course) with medium pressure (subjective I know) until I removed the marks from the ultrafine ceramic. I then lightened the pressure to what I would consider very light. After that I stropped on the bare leather for awhile, but couldn't discern much of a difference in the scratch marks (by this time, it was difficult to discern any scratch marks at all in the blades when observed under the 15x loupe, but they were readily visible when observed under 60x hand held microscope) both blades easily push cut paper (copier, magazine, newsprint, and tracing) at a 90 degree angle approx. 1" out from where I was holding it (much further than this and I couldn't keep the paper edge perpendicular to the ground for the blade to engauge) The whole process took about an hour for both knives combined. I don't sharpen my knives this way all the time, I just wanted to see what the ultimate edge I could get using this method was. My usual sharpening technique is to reprofile any new blade I get to 30 degrees ( unless its a chopper ie kershaw outcast, cold steel trailmaster, etc.) with the diamond stones, then refine through the medium, fine, and ultra fine using about 10-20 strokes each ( this doesn't remove all the scratch marks from the previous grit, but it does refine the edge quite a bit) if something doesn't feel right with the edge, I will examine it under the loupe, but in day to day sharpening I don't use the loupe much once I know the blade has the correct profile. I rarely use the strop, except on chisels, plane blades, and my high end steel knives ( where it does some good for more than a few cuts). *****Disclaimer***** I am not a sharpening guru, knifemaker, super uber tester (ala Cliff Stamp), or even any kind of supposed knife expert. I just wanted to see how sharp I could get a blade with these two tools, and then I figured I would post the results in case anybody else was curious.*****end disclaimer***** I hope somebody enjoys my little review/test here.

 

[clmayfield]

I have a few questions as I am looking to do the exact same thing you are. How much pressure did you put on the blade for fine and ultra fine?

What angle did you keep for the strop and how many strokes? Thanks.

 

[bigbcustom]

Pressure is pretty subjective. I used the same pressure on the fine and ultra fine as I did on the medium. I use a little more pressure when hogging steel with the diamond, but at no time do I really bear down. I believe in letting the stones do the work. For a rough idea, take a standard paperback book and fold it in half backwards like you are going to read the right side page....that takes about the same amount of pressure to maintain as what I use on the sharpmaker.

As for the strop, I held the strop in my left hand with the end resting on my bench and stropped the blade in a trailing manner with the spine just barely up off the leather (about the same as it looks when sharpening at 30 degrees on the sharpmaker but a little closer to the leather than the spine is to the sharpmaker stone) so I don't know what angle that is, but the light pressure on the edge portion was enough for the compound to cut/polish the steel. As for how many strokes, I didn't count, but several hundred I think. I just kept going until all the scratches from the ultrafine stones were gone then lightened up to just barely dragging the blade for about 100 strokes or so, then I flipped over and went at it for awhile on the bare leather (don't know if that did any good or not)

 

[clmayfield]

One more question: was the knife hair-popping sharp after the ultra-fine stones, or did it only get that way after stropping? I have been trying to restore my Shun kitchen knives to the factory edge and I can get them to shave easy enough on the Sharpmaker, but hair-popping is still a way off.

While my current blade is certainly good enough for cooking and probably even too polished for some applications (for example, cutting tomatoes), I love the fact that when I run the Shun factory blade an eighth inch over my skin, it will grab onto hairs and pull them off (plus, it saves my arm from bald spots). I just can't get there even with the Ultra Fine stones. I am thinking that I will need a strop to get there. Even so, if it is possible to obtain that level of sharpness without a strop, I would like to know so that I can correct the errors in my technique. It sounds like a loupe would be helpful.

 

[bigbcustom]

I seem to be able to get to "hair popping" with the ultra fine stones with some knives, but not others. After I read your latest post, I sharpened up a couple of my other knives and tried the "1/8" off arm hair thing" you mentioned, and they both trimmed the fur quite nicely. I then got a couple of henkels kitchen knives and tried it but couldn't get there. Tried a wusthof santoku and couldn't quite get there either damn near though it did "pop" the hairs up off my arm, but didn't catch and shear at 1/8" like the others. I wonder if it's a steel thing? or an angle thing? I bet there is someone (maybe Mr. Stamp) on here who could probably tell us exactly what's going on here. The two knives that I managed to do the 1/8" thing with were both spyderco fixed blades with vg-10 steel, I have no idea what the henkels or wusthof steels are.

 

[clmayfield]

Hmmm... My Shuns are VG-10, so I should be able to get there if it is a steel thing. At what point do you decide to move from the edges to the flats of the ultra fine stones? I do 20 - 40 strokes on the edges and shift to the flats and just go until it is about as sharp as I can get it, which again isn't quite there.

I get about the same sharpness with my chef's knife as with my paring knife, so I don't think it is an issue with length of blade/consistency across the blade although I will say that I wish the stones were a little longer for my 10" Chef's knife.

 

[bigbcustom]

for the last trial, I stayed on the corners of the stones until all scratch marks from the fine stones were removed from the blade. When you switch to the flats after that, you won't do a whole lot more good, but you will make a shallower set of same size scratch marks.

 

[HoB]

Nice one . Now you have to cut more stuff and tell us how it feels (like arm hair, toilet paper, plastic wrap, styrofoam....everything you can lay your hands on).

 

[Cliff Stamp]

Nice work.

First I profiled both blades to a 30 degree included angle with the diamond stones.

You might want to try cutting this down a bit further, even a couple of degrees will help a lot with the later stages. Essentially create a relief so that when you refine the edge you are only working on a very small section of the edge, ideal is just barely visible under magnfication about 0.1 mm or so wide.

I wonder if it's a steel thing? or an angle thing?

It is easier for blades to get sharper when the angle is lower because how you measure sharpness is to cut something and you raise the cutting ability when the angle goes down. If you really want to see just how easy sharpening to extreme levels can get then take a really fine grained steel which is really hard with a really thin edge and sharpen it at 3-5 degrees per side.

Some steels are fairly difficult to get really sharp for a number of reasons, some are just horrible to machine meaning they take much longer under the hones, this can be many times to one so if you are not looking at them under a magnifier you can get really frustrated because it is going nowhere. Another problem can be soft edges which buckle easily and form large burrs which are really hard to remove.

Some people will also complain about some steels not being able to get sharp due to coarseness of grain, but those people are either really extreme by what they call sharp and/or hone to extremely low angles (5 degrees per side) and not all steels respond well to those profiles. At the angles most people use, close to 15 degrees, even D2 will take a *very* sharp edge, just check Doziers.

-Cliff