WSKO: some knives not as sharp as others

[nola who_dat]

Excluding the WSKO, what other sharpening system would one recommend? Would whetstones be better / easier to obtain an edge? I looked at the Edge Pro but really don't want to spend $250. I looked at whetstones / DMT stones and those would run about what the KO costs.

 

[cbwx34]

I've estimated I'm at 22 or 22.5 but that could be off.

The X22 and X4 is already showing signs of wear along the edges.

There may be a clue in the above quotes. I think your angles may be too high, especially for a convex edge. The 2nd quote above, that your belts are already showing signs of wear, indicate you may be using too much pressure. Combine that with the first quote of your estimated angle, and your edge angle may be so high, it's not going to get very sharp. You could easily be over 30° per side.

Note one thing chado skins said... he lowered the angle to 15°, and got better results.

I surely do not want to spend an hour on one knife every time it needs to be sharpened.

WorkSharp is selling a "Kit Knife" pictured above... in part a knife that comes with no final edge ground in at all. I put a 20° edge on this knife in about 20 min. that would cut a circle in phonebook paper. It was on the BGA, with the stock belts, but the point is, spending an hour just to sharpen and not getting sharp, even with the standard setup, means something else is wrong. You should be able to sharpen in just a few minutes, and resharpening takes almost no time at all.

The image that IMightBeWrong posted in the other thread I referenced before...

should help diagnose this. If your bevel is small, chances are your angle is too high and/or too convex because of too much pressure.

Switching to a different sharpener might be the answer for you... a sharpener doesn't work the same for everyone. But the WSKO is certainly capable of getting the results you desire... so in the long run, might be better to solve the problem? Just a thought.

I feel that once I made a total of 60 passes that I was ready to move on to the X65 but just wasn't sure if I needed to spend more time with the X65 or not.

Once you raise a burr on an edge, unless you're removing damage, or removing the previous belt's grind marks, move on to the next belt. Making more passes doesn't do anything.

Hope that helps.

 

[nola who_dat]

Thanks for the info. I'll give it another try with a lower angle. May put the guide back on and see how that does.

 

[chado skins]

FYI i don't really use any "pressure" at all. i set the knife in the guide, turn on the machine and pull the knife through. it's probably easier to use too much pressure with no guide attached.

 

[chado skins]

cbwx, something you said reminded me of a question... using the same machine, same angles, same belts etc, i've noticed that my knives have different length bevels. should this be so? is that due to blade width, or what? i would imagine a longer bevel would be better, make for sharpening less, and easier to touch up in the future.

 

[nola who_dat]

Let me ask this question. If you use the 15* angle to sharpen all knives, wouldn't that eat up belts faster? Seems like it would.

I made a few passes at the 15* angle, starting with the P120 them moved to the X22. Seems like this may be the answer. I did the phone book test and it cut the paper without pulling but not smooth like I've seen in video's. IMO, I don't think the phone book test is an accurate measure to determine if a blade is sharp. The paper is so thin that a semi dull knife would be able to cut this paper. Wouldn't computer paper be a better gauge for sharpness?

Also, my wife used one of the knives that I said really wasn't sharp but she said it was. What does she know, right? LOL. then again, she was using it to cut chicken tenderloins which you could use a butter knife to cut.

 

[Doctor_big]

Thanks for the info. I'll give it another try with a lower angle. May put the guide back on and see how that does.

Definitely use the guide. If you're new to this thing, it'll help dramatically

 

[cbwx34]

cbwx, something you said reminded me of a question... using the same machine, same angles, same belts etc, i've noticed that my knives have different length bevels. should this be so? is that due to blade width, or what? i would imagine a longer bevel would be better, make for sharpening less, and easier to touch up in the future.

Sure... blade thickness, type of grind (hollow, flat, etc.), will contribute to the actual width of the bevel.

Let me ask this question. If you use the 15* angle to sharpen all knives, wouldn't that eat up belts faster? Seems like it would.

I made a few passes at the 15* angle, starting with the P120 them moved to the X22. Seems like this may be the answer. I did the phone book test and it cut the paper without pulling but not smooth like I've seen in video's. IMO, I don't think the phone book test is an accurate measure to determine if a blade is sharp. The paper is so thin that a semi dull knife would be able to cut this paper. Wouldn't computer paper be a better gauge for sharpness?

Also, my wife used one of the knives that I said really wasn't sharp but she said it was. What does she know, right? LOL. then again, she was using it to cut chicken tenderloins which you could use a butter knife to cut.

Usually phone book paper, because it is thin, will be more likely to tear rather than cut with a dull knife. It's also better at detecting imperfections in the edge.

I guess sharpening at a lower angle would wear the coarse belt faster, since you're removing the most metal with that belt. Beyond that though, I don't think it makes a lot of difference in belt wear... a bit more probably, but I wouldn't think it would be significant. Never actually tested that though.

 

[chado skins]

the best test for knife sharpness for myself is actually using the knife in it's intended purpose. i don't cut much paper at work

 

[bgentry]

I'm going to take one more stab at this, as I really want to help the two main posters in this thread.

After the 30 passes on one side and then switch to the other side and make 30 passes, is that considered deburring? Guess I'm a bit confused still with the burr and how to deburr correctly and about the apex.

Let's start with some terms so we're all on the same page:

Burr: A curl of metal that forms by pushing over the edge of the blade. When grinding on one side, the burr pushes up over that side and forms on the opposite side. The burr is very thin and weak, but can feel very sharp.

Apex: This is the cutting edge of a blade. The apex is where two flat planes (the edge bevels of a blade) come together and form a line. That line is the cutting edge. When we say "apexed", we are trying to describe an edge that has both bevels ground *fully* so that the entire blade is sharp. Sometimes someone will sharpen only part of the blade and we don't consider this "fully apexed". It's a fancy word that has a precise meaning in the context of sharpening.

Deburring: The act of removing any remaining burrs from either side of the blade. This is usually done with light force and a small number of strokes or passes. It's common when trying to remove the burr from one side, to have the burr form again on the *opposite* side. We call this "Chasing the Burr" because you are chasing it from side to side trying to get it to go away! Deburring is a more subtle part of sharpening and can be challenging. At least it is for me.

To your questions:

This is IMPORTANT: You Do NOT need to do equal passes on both sides. In fact, once you form a burr on one side, on the full length of the edge, you can form a burr on the other side with just a few passes. So in your example of needing 30 passes on the first side, you'd probably only need 3 or 4 on the other side to form a burr. *Unless* you were switching sides every few passes. The key is when the burr forms. After it forms on one side, it takes very little effort to form a burr on the other side.

I can say that after making 60 passes the blade is choppy as it will catch when passing it over a towel. So I'm not sure if that's the way the blade is supposed to be or not. I did run the blade through a cork, it felt smooth but I could see the blade had remnants of the cork due to the choppiness of the blade.

I'm pretty sure you have a GIANT burr on one side of the blade. If you do, you should be able to catch your fingernail on the burr. Try sliding your fingernail down the side of the blade, and OFF of the edge. Go slowly and if you have a burr there, it will stop your fingernail right at the edge. If so, you need to remove the burr. Try using the next finer belt to remove the burr. Use the slowest speed of the WSKO. Check for the burr after every pass. See if it switches sides. When it's very small or gone, run the blade through cork, and then test for burr again. Light passes on one side and then the other, are a very good way to minimize the burr, or eliminate it completely.

You may have to use VERY light strokes on the belt to remove the burr, but it can be done, at least enough to slice printer paper. You'll get there.

Good luck to you and anyone else trying to get great results from the WSKO. You can do it.

Brian.

 

[chado skins]

i touched up a few knives today. my forschner chefs and cold steel chefs knives already had a 15 degree bevel from the KOWS so i started with the x22 and give it about 15 passes per side. they both came to life very nice. i can see how it may take a long time when intially sharpening a knife to get the bevel down, grinding all the shoulder material down.... then in the future you re really just touching up the apex, so a lot less grinding. this is getting easier!

another thing i've noticed... it seems the knives with thicker steel have a much wider bevel. it looks real nice, but two of these knives, one a henckles, the other some sort of german steel, don't get very sharp. the knives with the smallest bevels seem to be the thinnest steel, and these knives come to a nice sharp edge. the thicker steel just doesn't want to get nearly as sharp as the thinner ones.... any remedies for this? or is it in my head??

 

[Kloepper Knife Works]

i touched up a few knives today. my forschner chefs and cold steel chefs knives already had a 15 degree bevel from the KOWS so i started with the x22 and give it about 15 passes per side. they both came to life very nice. i can see how it may take a long time when intially sharpening a knife to get the bevel down, grinding all the shoulder material down.... then in the future you re really just touching up the apex, so a lot less grinding. this is getting easier!

another thing i've noticed... it seems the knives with thicker steel have a much wider bevel. it looks real nice, but two of these knives, one a henckles, the other some sort of german steel, don't get very sharp. the knives with the smallest bevels seem to be the thinnest steel, and these knives come to a nice sharp edge. the thicker steel just doesn't want to get nearly as sharp as the thinner ones.... any remedies for this? or is it in my head??

Welcome to the world of edge geometry. Chances are that the wider grind takes more passes, so thanks to an increased chance of making a bad pass, you probably are. Also thinner knives cut and sharpen easier. Think of it as the difference between the hull of a racing boat vs a barge. The resistance to cutting decreases dramatically with a knife that is ground thinner behind the edge.

There are tons of more in depth threads on this, read up on it and may become one of the biggest factors you consider in future knife purchases.

 

[Airquotes]

Hey guys, thought I would post this question here since it seems like the most active Work Sharp thread. I've already learned a lot reading through it. I bought the regular Work Sharp and have some success in getting knives sharp but I still don't feel totally satisfied with my results. I've managed to get my Kershaw Cryo pretty sharp as well as another dirty old pocket knife. The cheaper steels are pretty easy. They will shave and cut paper.

I was wondering if you had any tips on sharpening S30V. I have a Spyderco PM2 that strangely didn't come sharp from the factory that I'm trying to sharpen. I can get it to shave hair fairly well but it won't slice printer paper cleanly and it doesn't feel that sharp when I run my fingers along the blade. I've been using the P220 and then the 6000. It's defiantly cutting away material because I made the mistake of leaving it in the sharpener at the hilt a little to long and it put a slight bow in the blade. Not sure where to go from here. I gave it another pass with 10 strokes of the P220 and around 50 of the 6000. Got a little sharper but still not great. I don't want to keep hacking away at it and deform the blade with no result. Any suggestions for sharpening S30V on the regular Work Sharp?

 

[chado skins]

should i be doing anything different with japanese steel knives? i have a shun and two miyabi henkles here... not getting much luck with them. i spent some time on the coarser belts, and i can see a new bevel created. i progressed through the belts but the knife feels pretty dull. is this just not the type of abrasive for jap knives? i know whetstones are preferred... any tips for these knives or do the same rules apply? (maybe spend more time with coarser belts?)