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An article by Larrin, "How Chipping of Edges Happens at a Microscopic Level" (on Knife Steel Nerds), debunks the idea of coarse edges due to the increased propensity for chipping and faster dulling of the blade. As noted by Dr. Vadim Kraichuk, "Meat plants are well aware that knives with coarse edges worsen product presentation and increase operators' fatigue and repetitive strain injuries. On the contrary, polished edges improve product quality through higher value cuts and increase throughput."

It is a common, but quite bad, practice of drawing the newly sharpened knife edge through a piece of wood or some other media to "rip off" the remnants of the burr. When this is done, the ripped off metal builds up on the front of the slice, and you then drag the rest of the edge through this crud. This crud, together with breaking off of ledges of material along the edge, will roughen the edge and worsen sharpness.

The scanning electron microscope (SEM) images to the pictures lined show the burr on a knife in the 1st image, that was then "ripped off" by cutting cross-grain into a piece of redwood in the 2nd image - loss of the sharp edge is obvious.

https://sharpeninghandbook.info/GT-Knives-Ripped-Burr.html

Key take-away from these photos : don't skip the honing step.

Dr. Larrin Thomas' book, Knife Engineering: Steel, Heat Treating, and Geometry (2025), discusses burr removal quite well.

This is really good.

I bought the SVD-110 Tool Rest and have been using it with the DF 250 to sharpen mower blades and its quick and really precise, no truing and I use the marker method (most blades are coming up between 35° - 40°. 

If the blade is uneven, I use the KJ45 with no problem.

I would love to see a video or pics of this.  It sounds like a great approach. 

I found that with a dissecting microscope I can see the size and shape of the burr. Years ago I used this method to refine my knife-sharpening skills. I was able to check whether or not a burr went along the full length of the blade. I can see the size and shape of the burr and as others have mentioned it does indeed depend on the type of steel and the grinding direction, but it doesn't matter.

Nowadays I keep a piece of an old bath towel handy and run the surface of the blade across the towel. Moving the knife away from me with the cutting edge facing towards me. The burr will catch fine threads of the towel and with good light and a magnifier I can easily see them, telling me if there's a burr all along the edge. Then of course I sharpen the other side of the edge and do the same. Now I know the knife is sharp and needs only to have the burr removed.

The knife is usually either a kitchen knife or a pocket knife and is now sharp enough for everything that do with it. I know that other techniques can get an edge sharper than that, but I'm of the opinion that that effort is just for show because as soon as the knife is used it will not be any sharper than it is with my technique. I don't have expensive knives and I've never used anything other than the SG grindstone and the honing wheel with the Tormek honing compound.

I use the same technique to sharpen tools, and modify it slightly for a lawn mower blade.

Herman,

That's an interesting idea.  What magnification are you using?

Rich

Thank you Gerd.  I appreciate your kind words.

John,

I've cataloged all that, and more at:  https://sharpeninghandbook.info.

Rich

I saw that Tormek now has a new knife sharpening kit, the KSK-106 (https://tormek.com/en/products/kits/ksk-106-knife-sharpening-kit).  

Of interest to me is the new CU-8 Edge Loupe.  That part is not listed in the Tormek catalogue, but I am betting it is the same as the magnifying glass in the DBS-22 Drill Bit Sharpening Attachment.  Any thoughts from anyone else?

I agree about using the micro bevel.  It is a better practice anyway as it will use up less of your SJ grindstone.

Here's what I've compiled about micro bevels https://sharpeninghandbook.info/MicroBevels.html.

How do you envision these being used?

I use a machinist's hand file.  It works fine. 

I plotted the speed of the grinding surface vs. the diameter of the grinding wheel (for the T-8).  As shown in the chart, at 220mm, the speed is 88%, and at 180mm, it is 72%.

Ken,

That is an interesting point that I've not considered.  Thank you.

Rich

Dave,

Here is more details:  https://sharpeninghandbook.info/WW-SpindleGouge.html

Rich 

There are ways to extend the useful life of a grindstone.  I've catalogued some here:  https://sharpeninghandbook.info/Grindstones-StoneLife.html. 

1. FVB vs. MB 102
2. Leather wheel (2 pcs) vs. Felt wheel (2 pcs) (and I have WSKO ELIT )
3. SVM 45 vs. KJ 45 (by SVM 45 I mean custom)
4. KS 123 vs. app

Andy,

1. MB-102
2. Leather honing wheels with PA-70
3. KJ-45
4. KS-123

Rich