Help with Correct Sharpening Protocol

[MartinC]

I have an kitchen knife that I am trying to sharpen and I'm not having success. I'm not sure the brand of the knife, no real markings so I suspect it is a low-end knife.

I have the SG-250, SJ-250 (rookie mistake in buying), the LA-220 and the CW-220.

Currently I am only using the SG-250 & LA-220 for this knife. The knife started out at a BESS of 580. I graded the SG-250 to course and ran the knife about 10 times, then graded to fine and did 4 passes. Then to the LA-220 for 2 passes per side. I used the same angle for all steps. When done I am still close to the original BESS score. Currently I am at around 420.

Given what I have, what would be a good protocol to get the best results. Should I add the SJ-250 to the mix, should I tweak the honing angle a few degrees. I don't think either one of those thoughts Will magically get me closer to 100 BESS.

Thanks


Any thoughts on how to troubleshoot this?


Every time I think I know what I'm doing, I learn that I don't.

[Scotty]

I would not worry about the SJ at this point.
Not sure what bevel angle you used.
You might try grading to 220 and run alternating passes, edge leading, at 15 degrees ( per edge)with moderate pressure until you get a burr entirely along one side of the bevel.
Should take about 1.5 seconds per blade inch.
Then try one quick light pressure pass on the opposite side(thin the burr).
If you suspect low quality you might try honing at this point. If that shows improvement, then regrind at 1000.
Some low quality steels do not respond well to grinding at much over 400..
Check your angle.
If you are honing at too high of an angle you might round the edge.

[cbwx34]

I have an kitchen knife that I am trying to sharpen and I'm not having success. I'm not sure the brand of the knife, no real markings so I suspect it is a low-end knife.

I have the SG-250, SJ-250 (rookie mistake in buying), the LA-220 and the CW-220.

Currently I am only using the SG-250 & LA-220 for this knife. The knife started out at a BESS of 580. I graded the SG-250 to course and ran the knife about 10 times, then graded to fine and did 4 passes. Then to the LA-220 for 2 passes per side. I used the same angle for all steps. When done I am still close to the original BESS score. Currently I am at around 420.

Given what I have, what would be a good protocol to get the best results. Should I add the SJ-250 to the mix, should I tweak the honing angle a few degrees. I don't think either one of those thoughts Will magically get me closer to 100 BESS.

Thanks


Any thoughts on how to troubleshoot this?


Every time I think I know what I'm doing, I learn that I don't.

I don't know your sharpening skill level... but I always suggest that, if something is not working, go back to the basics.  Mark the bevel with a Sharpie (both sides... this will help show any issues), make sure you create a burr on both sides, then light alternating passes on the stone to reduce it, then hone it off.  (I say this becasue your post makes me wonder if you're just doing a set number of passes on each side, vs. doing enough passes to get the proper results).  If you don't think the burr is getting removed, then raise the angle a couple degrees and make a few more passes.

If you've done all this, then try Scotty (and probably others) ideas.

[BradGE]

My advice, similar to what has been mentioned, is to make sure you get a burr during the sharpening.. Don't worry about counting passes on the coarse grinding - you have to go until you have a burr. Sometimes that will be 3 passes/side, sometimes 20 passes/side etc.   

Honing is probably fine, but you could verify that you are getting the full bevel by using a sharpie.

And finally you could consider a strop as a finishing touch, which usually gives a bit of a boost to BESS scores.  But with the SG and leather wheel you should be able to get close to 150 or so...

[Millerti87]

Have you tried increasing the honing angle by .2-.4* ?

[John_B]

When I do a knife for the first time or if I am changing the angle I always do an end to end inspection with a magnifying loupe after the first few passes. What I often find is that the original bevel is not even from one end to the other and for that matter each side may be at a slightly different angle. If you don't see that the grinding is going to the edge for the complete length you will never get a complete burr end to end. I never count passes but rather look for results. Each knife is different. Once I see that I have gotten a burr along the entire knife edge on both sides I will regrade the stone fine and continue with light passes. My last pass is as light as I can go. For most knive I will then hone at +1.5°. This process yields an exceptionally sharp knife.

[MartinC]

Thanks

I think the problem was not spending enough time raising the burr. As a follow up question, is it still best to alternative sides when working to raising the burr?

[cbwx34]

Thanks

I think the problem was not spending enough time raising the burr. As a follow up question, is it still best to alternative sides when working to raising the burr?

I don't... I work one side, raise a burr then switch sides.  It would be hard to detect a burr if you switch sides every time, IMO.

But, if I work one side a bit, and don't raise a burr, I'll switch sides... to keep everything even.

Once the burr has been formed on both sides, then I make a few light alternating passes, to reduce it.

[tgbto]

I personally don't do more than two strokes per side. This way I'm pretty confident the bevel remains centered. This only exception being a few knives that were sharpened assymetrically from the factory, where I do 4/1.

I've not noticed that raising a burr was much faster when experimenting with not alternating, but if would make for an assymetrical edge eventually. I can usually tell when there is a burr even after a single stroke. Then I lighten the pressure on the very last passes only when I can feel the burr along the entire length of the edge.

[nevertakeadayoff]

I deburr by moving the stone manually and holding the knife handle with the other hand. I find it too difficult to deburr by just using light pressure and quick motion.

[tgbto]

The last (15th) time I read the Tormek manual, I noticed that the recommended method is to work on one side till you raise a burr and then... sharpen an equivalent amount of time on the other side.

I am not sure I could keep track of how much I've sharpened one side before switching sides, except on knives in a very good condition where just a couple of passes are needed. What do you think ? Do you also think that switching sides often (every 2-3 strokes) takes much longer to raise a burr ? I am not sure I could set up an experiment with a controlled initial condition to make accurate comparisons, and I do not sharpen enough knives to have a firm opinion on this.

[cbwx34]

The last (15th) time I read the Tormek manual, I noticed that the recommended method is to work on one side till you raise a burr and then... sharpen an equivalent amount of time on the other side.

I am not sure I could keep track of how much I've sharpened one side before switching sides, except on knives in a very good condition where just a couple of passes are needed. What do you think ? Do you also think that switching sides often (every 2-3 strokes) takes much longer to raise a burr ? I am not sure I could set up an experiment with a controlled initial condition to make accurate comparisons, and I do not sharpen enough knives to have a firm opinion on this.

Personally, I don't think there's an answer to your question.  I doubt it takes "much longer" to switch sides every few strokes, so if that works for you, there's nothing wrong with it.

I think over time you develop a feel for how long you've worked one side, along with the obvious visual cues.  I've realized over time that most knives don't come sharpened that well to begin with, so it's hard to keep a blade: centered, at the same angle, etc. by following a set procedure doesn't work that well.  I may need to work one side more than the other to begin with, just to even things up.

So, I guess if I had to give an answer it would have to be... pay attention to what the knife is telling you, whether you switch back and forth or work one side until you raise a burr.  It's more important to do both... raise a burr (on both sides) but also make things even (or whatever outcome you want).  I think the advantage of using a water cooled slow moving wheel is the ability to work one side longer to get the job done, which overall is a bit faster, especially for repairs or really dull knives.  And as always, a Sharpie type marker is your friend.

BTW, hats off to Tormek, or any knife sharpener manufacturer who puts "raise a burr" in their instructions, vs. sharpen one side X number of times, then switch and repeat, and your knife will be sharp.