Sharpening/putting an edge on an Knife

T

Tyler Thomas

Joined
May 30, 2019
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5
As makers What do you guys use to put an edge on your knives? Do you use machines or sharpening fixtures or do you use your belt grinders?
 
I find jigs and fixtures more trouble than they are worth.
Most knives are sharpened on the belt grinder with a 120 grit belt. The grinder is running at about 10% speed.
I sharpen most kitchen blades on a variety of stones.
 
Kitchen blades are so thin BTE I only shape gently with a well used 600 grit diamond, then white ceramic and strop.
Other than that I set the edge on 240 grit slowly on platen, then refine by hand. Usually brown then white ceramic before strop. Commonly just brown ceramic and strop, for a good working edge.
 
This is almost exactly what I do with kitchen knives. They're ground so thin they only take a few passes to get a burr on diamond. I then go to 1000 before stropping.
Scaniaman said:
Kitchen blades are so thin BTE I only shape gently with a well used 600 grit diamond, then white ceramic and strop.
Other than that I set the edge on 240 grit slowly on platen, then refine by hand. Usually brown then white ceramic before strop. Commonly just brown ceramic and strop, for a good working edge.
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On my kitchen knives I sharpen them on water stones. I set the bevel on a 400 grit (only takes a handful of strokes to raise a burr), then take them through 1000 and 3000 grit stones and finish on a leather strop with green compound. I built a rather unnecessary and overcomplicated jig to hold blades at a consistent angle when sharpening on normal stones. It works well and I use it when I really care about getting a perfect edge. When I'm just sharpening something quickly for myself I usually just do it by hand on the same stones.
 
Fwiw ... I use a 240 grit belt on my grinder, running (like Stacy) at 10% speed. I found i was really BAD at manually defining a 15 degree angle, so created a small fixture (not a jig) that helps me set that angle, then move it away and hold that angle by hand. I would like to add sometime soon a water source to keep the edge REALLY cool.

I no longer go to higher grits, as the micro serrations at 240 grit seem to help a lot with slicing effectiveness
 
I use a Iot of exotic steels at high hardnesses, I never let the edge on my knives touch a belt, I only sharpen by hand with Bonded CBN and Diamond stones.
I grind to a thin plateau and establish the edge by hand, the stones cut very fast. No issues with burned, fatigued, torn out edges.
 
I set the bevel initially on a diamond stone, then use my edge pro to go through the grits, last step is a loaded leather strop. I do a lot of thin, high hardness knives. I never use the belt grinder to sharpen.
 
Willie71 said:
This generated a lot of discussion when released, but read through this as food for thought./
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Im gonna get flamed for this ... but what the heck :) I earlier read through that knifesteelnerds article ... and my take away is that a grinder not so much "ruins" the edge, as there is a (relatively slight?) degradation in longevity of edge. so my take away is that it depends on you (or your customer's) tolerance/whishes for the best possible longest-lived edge, as opposed to something that is fairly close, but still not quite as long lived.....

Just as reference ... a santoku (AEBL, 62 rockwell) I made for my son's roommate back in Sept or so, has apparently seen daily use in food prep since then ... and they indicate it still remains sharp. I sharpened that guy on the grinder at 240 grit. that parallels comments by a buddy I have given a couple knives to....

My guess, though, is that the higher the harness (like what DeadboxHero says...) , the more the risk of not getting everything you can/want out of that high hardness?
 
The other huge variable is how people define 'sharp' when they're talking about their knives. I'm a bit snobbish about my kitchen knives and consider them not acceptably sharp when they stop falling through food effortlessly. At that point it still cuts very well and is far sharper than the out of the box edge on knives people buy from major manufacturers, but it's not what I like in an edge. This means I strop my knives weekly and take them back to a 3000 grit stone monthly to maintain the edge quality I prefer. So no matter how well a knife was sharpened with a 240 grit belt or stone I wouldn't consider it sharp by my standards. But if I took that knife and gave it to my father who doesn't take care of his knives he'd be raving about it and would probably call it sharp after using for a few months because the toothy edge could still cut through food safely. It's all a matter of perspective.
 
CallumRD1 said:
...consider them not acceptably sharp when they stop falling through food effortlessly. ..... This means I strop my knives weekly and take them back to a 3000 grit stone monthly to maintain the edge quality I prefer.
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Oh ... I definitely agree that it is a matter of perspective. I have a 6000 grit stone (and steps below that) ... I have taken quite a few of my knives up to that level ... and while I agree that at that point they are really nice :-) :-) ... nevertheless I have (for whatever reason) grown to like the "feel" of the 240 grit microserrations. But then again ... I have never been able to get a knife to the point where they just "fall through food". Can you send a video of that??? :-) (just kidding)
 
CallumRD1 said:
The other huge variable is how people define 'sharp' when they're talking about their knives. I'm a bit snobbish about my kitchen knives and consider them not acceptably sharp when they stop falling through food effortlessly. At that point it still cuts very well and is far sharper than the out of the box edge on knives people buy from major manufacturers, but it's not what I like in an edge. This means I strop my knives weekly and take them back to a 3000 grit stone monthly to maintain the edge quality I prefer. So no matter how well a knife was sharpened with a 240 grit belt or stone I wouldn't consider it sharp by my standards. But if I took that knife and gave it to my father who doesn't take care of his knives he'd be raving about it and would probably call it sharp after using for a few months because the toothy edge could still cut through food safely. It's all a matter of perspective.
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This is so true. I have a few customers that have had knives for over a year. I tell them to bring them by for a sharpening and they claim they're still sharp as ever. I give a funny look and so OK.
 
I normally use waterstones - 400 (on hunting knives, for kitchen knives and folders I find it to be unnecessary), 1000 and 8000 grit, folowed by a leather strop.
 
I am just beginning to mess around with what "sharp" I want in different knives. I'm learning about angles, how different grits give different types of sharpness and have also begun to realize there is a certain subjectivity to what is sharp enough. In the end it comes down to the use of the knife and your own personal preference. For me my edc and hunting knife seem just fine sharpened on a belt with 240 grit and then stropped. I go much finer with my kitchen knives.
You have a bunch of great ideas here. Try a couple of them and find one that suits you.
 
Fallbrook Forge said:
I’d like to see that too.
Can’t say I’ve heard of a knife “falling” through carrots.
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HB67D5v.jpg
 
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