Hello, Grepper!

[napaknives]

Mr. Grepper:   I just got off the phone with Mike Brubacker, and he suggested that I contact you.    He said that you are producing very sharp edges, very quickly, and very simply.  

 A bit about me:        Retired chef, sharpening once a week at a local farmers market.
                               Using a 4-step belt sander system to sharpen.
                               Taking 2-3 minutes to sharpen and remove the burr (problematic).
                               Edges test at 230-270.  OK sharp, but not much tooth.

OK, I'm frustrated.  I want sharper, toothier edges.  Could you share your technique for sharpening?  
Thanks so much.................Dan

[grepper]

Whenever I see numbers 230-270 I suspect that not all the burr is removed.  Get a good loupe or better yet a USB microscope and see if what you are doing is leaving burr.   Maybe that’s what’s going on.  Just a guess.  I'm not saying that 250 or so is not a perfectly good level of sharpness.  In fact it may have better edge retention in the long run than a 150 edge.  We still need to do some edge retention tests to see how that pans out.
 
I don’t do anything very fancy at all.  I use a Kally with a home made knife rest to maintain a constant sharpening angle,  a 150 grit belt (I like the Cubitron belts) for sharpening, and the rough side of a Surgi-Sharp leather belt for deburring.  The Kally sharpens edge trailing when sharpening.
 
Unless there is a lot of steel to be removed, I use a very light touch when sharpening.  Light enough so there is basically no visible belt deflection.  As soon as there is any burr, flip the blade over and do the other side.  I do that just to keep the amount of burr to a minimum.  Once the edge is evenly ground it’s easy to get a nice, even little burr along the entire edge.  Then flip the blade and form the little, even burr on the other side.  Then I do one or two quick extremely light passes, barely touching the blade to the belt, on each to lessen the burr.

A note on the burr:  Once the blade is sharp, forming a burr takes only one, light pass.  If you can feel the burr, that's all that is needed.  Sometimes the burr can be difficult to see, but easy to feel. There is no reason to make a big, gnarly burr.  It's not needed and is more difficult to remove.  Create as little burr as possible.
 
For deburring, I do a light pass on each side at sharpening angle, and quick, very, very light passes at about 45° to the edge to bend the burr back and forth. 
 
I put a little compound on the belt months ago and have not added any since.  I wish I had just used a little oil instead, just to make the belt a bit less dusty as a perfectly dry belt tends to be a bit dusty when using the rough side.
 
I don’t use compound because I don’t want to grind away the toothy edge.  I don’t want a polished edge, and I don’t care at all about a shiny bevel.  Burr removal for me is just friction, and bending the burr back and forth until it breaks off.
 
I just sharpened a knife last night.  130 in the middle of the blade, but 265 on the rounded part near the tip.  I checked with a loupe, and sure enough, there was burr in the 265 area.  I did a couple of quick, moderate pressure passes on the leather belt in that area and the reading was 165.  Good enough for that knife. 
 
With a really dull blade it’s OK to use more pressure just to get the edge basically sharp.  The problem with heavy pressure is that it forms a substantial burr that is difficult and time consuming to remove.  If I have to do that, the normal, very light pressure sharpening thing removes most of it during sharpening.
 
Wow.  Writing this down appears WAY more complicated than it is!
 
Basically I just do very light pressure sharpening with a 150 grit belt and deburr gently on the leather belt.  This seems to reliably product nice toothy edges 150 or less.
 
I hope that is not disappointing.  There is no real “trick”, and nothing special at all other than I use a very light touch for both sharpening and deburring, and don’t use compound on the belt.  It’s very simple and not complicated.  Basically, grind the edge at 150 grit, remove the burr.

I think there is a tendency to way over-think this this stuff.  If what you are looking for is a highly polished edge with a mirror bevel then a grit progression during sharpening and compounds for polishing is required.  But for a nice, sharp toothy edge there is really nothing to it.  
 
Hope that helps.  I’m more than happy to answer any questions if you have some.

[napaknives]

Thanks, Mr. Grepper.  Sounds pretty simple.  I will try your method.  Could I use the slack part of the belt (150 grit and leather)?  This could really minimize my setup as well as my sharpening time.  Clients don't like to wait long for their knives!

                         Again, thanks..............Dan

[EOU]

Thanks Grepper. We listen and talk to Grepper frequently because he has a lot to tell and we have a lot to learn. For us it's all about the burr and burr removal and Grepper can sniff out those last vestiges of burr from a mile away. As you can see his process is almost beyond simple but don't overlook the fact that he is also a skilled practitioner using well designed modifications to his Kally. For us, the secret to achieving that last 30 - 50 points of improvement is to get rid of that bubbly line of crud (crud; technical term for what we think represents some element of the burr) that resides only on the burr side of the edge. It's only visible to us with the aid of an optical microscope. We're still not certain why it's there or how it is formed but there is little doubt, it's there and affects the sharpness of the edge. This line of crud may be removed easily or, in some cases, might take a case of dynamite to remove. Once you dynamite the edge a significant portion of the tooth will be gone. Grind pressure seems to be a key preparatory element and that's why Grepper advocates for a couple of light passes before active burr removal steps are taken. 

Grepper uses a little different set-up than we do and that, coupled with an advanced skill level, likely contributes to the ease and speed with which he turns out  excellent results. We have to work at it a little harder around here. We use a guided system with our Kally as well but a little different than Greppers. We think his system is better (he's better as well) and will be rectifying that deviation soon. In the mean time, here's how we pick up and loosen the crud before the active deburring process begins. Once the grinding process is finished we turn the Kally motor off and flip the knife over to the side where the burr has formed. It's still in our angle guide. We then pull the belt down manually, belt lightly touching the edge, inch and a half or two of belt at a time, then slide the knife over, inch at a time, in the guide until we reach the other end of the blade. When we use this method we avoid chasing the crud from one side of the edge to the other (don't yet know why). Then deburr on the leather belt or a Sharp Pad.  Crud and burr are gone. We make sure the edge is aligned and straight with a few strops on a Sharp Pad  and we're looking at an edge 140 - 200 depending on the knife.  Be it 140 or 200, if you lay your thumb on the edge a shiver will go up your spine due to the combination of sharpness and tooth in the edge.

So what's the best way? Without a doubt Greppers instructions are the ones to follow.  We only propose this deviation if you're having trouble in removing crud while preserving the tooth. Thanks to Grepper and Napaknives for this thread!

[grepper]

Mr. Dan, I never sharpen against the platen.  There is no need to.  Always about 2" above it. I've had good luck using this belt.  I really like the Cubitrons:
https://www.rshughes.com/p/3M-Cubitron-7...111_67951/

It's YF weight, so not too wimpy and not overly stiff either.  I use light pressure when sharpening so even with the YF belt there is little, if any belt deflection and very little if any heat generated.

Not only is against the platen way more aggressive than I need, but also due to the type of knife rest I use when attempting to sharpen against the platen it's easy to suck the blade down between the rest and blade.  No fun when that happens! Once it caused me to suffer epidermal leakage.  

About 2" above the platen provides a plenty stiff belt, but it also has a little forgiveness to the belt and produces a very nice, even bevel and edge.  

With a 150 grit belt very little pressure is needed which reduces the burr and makes burr removal much easier and quicker.

The 120 grit Cubitron II's work OK too, but they are a little gnarly and I seem to favor the 150 grit currently.  In my quest for toothy I've even tried 40 grit Zirc belt.  It worked and was sharp, but the edge was more like a saw than a knife.  

Grinding the edge is really not that difficult.  The most difficult and important part, as Mr. EOU eruditely states, is complete burr removal.  For a smooth and polished edge there is nothing to it.  But for a toothy edge, it becomes trickier when trying to not remove the "toothy" during the process.

---

I would like to add that I am far from an expert knife sharpener.  I do what I do because it seems to work for me, but I have no idea if what I do will work for someone else.  Maybe some of the stuff I mention will be helpful, or not, who knows.  Hopefully there are some useful ideas, but it certainly isn't the only, or even the best way to do things.
Whatever I suggest, I'm sure that you will end up doing whatever works best for you anyway.

[napaknives]

Thanks so much, Mr. Grepper.  And thanks for the RS Hughes referral.  I've got some 120 grit Cubitrons from TruGrit, but I think I'll get some 150's from Hughes.  Thanks again...........Dan

[Ken S]

Interesting and pertinent topic. By the way, welcome to the exchange, Dan. Grepper and EOU, fine replies.

I was especially interested in your comment about placing the knife edge two inches above the platen. Am I correct in thinking that this would cause the ground edge to be a controlled slightly convex shape? This should reinforce the edge, making it longer lasting. Good tip, Grepper.

On the Tormek forum, I have advocated using Irwin (formerlt Marples) Blue Chip chisels (3/4” width) to become familiar with the machine and the process. I use them extensively for testing different grinding wheels and techniques. The large, chisel size bevels are easy to compare visually. I have accumulated about a dozen of these (same size). My point here is that I believe there is value in working with at least two (preferably more) identical knives to see the differences in things like different grit belts and different touches. I suggest using moderately priced knives of good quality. Using identical knives eliminates variables in steel and manufacturing. The testing should include the kitchen as well as the sharpening station.

I should state that I am basically a chiseler. The knife people on the forum generally disagree with me on this point. I respect their right to be wrong.  

I do not believe that time spent mastering basic skills is wasted. Nor do I feel that investing a little more in good learning knives is wasted money. 

Ken

[napaknives]

Good suggestions, Ken. Thanks...............Dan

[grepper]

Slightly convex Mr. Ken, but not very much. The belt is stiff enough and the tension is high enough and I use very light pressure so there is little belt deflection, but no doubt very slightly convex.

[Ken S]

Slightly convex makes sense.

There is another element in your technique, Mr. Grepper, which you modestly have not mentioned. I know you have worked hard and with dedication to acquire your knowledge. The same method might work for many of us   Lest I serm pious, I include myself in the group who would benefit. Our journey is lightened by pioneers like you.

Keep up the good work.

Ken