Knife sharpening techniques for all

x SF med

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AND..... back to our regularly scheduled programming....

@Ooh-Rah posted some pictures of blade styles....
Which ones are going to be the hardest to sharpen? (there are 6 difficult ones and one may not be very obvious)
Why? (think hard)
How do you overcome the obstacles presented? (think more harder)

let's get some answers before @Barbarian or I answer or amend responses....

Put on your thinking caps boys and girls... this requires you sciencing a little.... bwahahahahaha!!!
 

Ooh-Rah

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For reference, below is the pic that @x SF med is referencing above.

My attempt at which blades would be most difficult to sharpen:

- I find my American Tanto can be a challenge, but seems to go better if I just treat it like two separate blades.

- The Sheepfoot and Wharncliffe also seem like they would be tough because the blades are so straight and have very precise points...I think it would be easy to mess those up.

- The Talon I would not even know where to start on a stone. Just looking at it makes me think I'd cut myself with it somehow

- The Kurki and the Nessmuk also appear intimidating because similar to the Talon, the blade curves inward at the hilt.

- Really any of the blades with rounded edges are also potentially complicated as not only do you have to hold your angle, but as you get to the curve, you are forced to lift the butt of the blade so that the rounded edge stays at your desired angle.

To overcome the blades like the Talon or the Kurki, I would learn to use a rod type sharpener so that I can keep my blade focused directly to the sharpener and not find myself in a situation where I have two parts of the knife on the store at the same time.

To overcome the fear of damaging the point of the sheepfoot or wharcliffe, I don't know. Other than for this type of knife pay special attention to ensure that your angle remains consistent so that you do not accidently round the tip.

I will check back later for other responses, and/or correction from @x SF med or @Barbarian -


 

x SF med

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Well... @Ooh-Rah, you're close.... but sheepsfoot and wharncliffe are easy to sharpen.
The talon (karambit) is a bitch to sharpen.
You are right about the tantos - treat the edges as 2 separate blades.
So there are 3 of the 6 I noted, you are kinda wrong about the 'curved' (convex or normal edge) profiles those are easy to sharpen once you've got your angles down and practice keeping the cutting edge at that angle.
Kukri and Dao are difficult also, any recurve is going to be a bitch to sharpen, because you can flatten an already sharpened area.
The hidden hard to sharpen knife is the dragon's tooth/needle point - because you can break off the tip while sharpening or have mismatched angles ...

Once we get into more of the mechanics you'll understand more - a lot of the issues will come into play one you understand the spine ridge issues on double edged knives.

Not a bad run, for a Marine.:thumbsup:
 

Ooh-Rah

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Not a bad run, for a Marine.:thumbsup:
Thank you.

My Randall arrived today. I now know the definition of "sharp". It is the first knife I have been nervous about handling-

It will be some time before I make an attempt to touch that blade up on my own.
 

Barbarian

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Ooh-Rah said:
- The Sheepfoot and Wharncliffe also seem like they would be tough because the blades are so straight and have very precise points...I think it would be easy to mess those up.
Those are the two easiest blade types to sharpen. I understand your anxiety about the tips though. Most folks overthink the tip when learning to sharpen. When you're sharpening a blade tip, you just focus on keeping the same edge angle as the rest of the blade. If you sharpen the edge correctly, then the tip will naturally become sharp as well. Of course, things are more complicated if you've broken the tip off, but that's a different matter all together.

Congrats on the Randall. If you decide you don't like it, you can send it to me. I'll dispose of it properly.
 

Ooh-Rah

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I'm to the point where I want to get some practice in, but realize that the tools I currently have will do more damage than good. In addition, we can talk about technique all day, but unless I can see it demonstrated, it is difficult to practice.

A friend of mine is a chef and she sent me this video as something she practices for her kitchen knives. Agree? Disagree? Recommend something different?

If nothing else, get to the end and watch the tomato demonstration - that is a very sharp knife!

 

Barbarian

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I'm to the point where I want to get some practice in, but realize that the tools I currently have will do more damage than good. In addition, we can talk about technique all day, but unless I can see it demonstrated, it is difficult to practice.

A friend of mine is a chef and she sent me this video as something she practices for her kitchen knives. Agree? Disagree? Recommend something different?

If nothing else, get to the end and watch the tomato demonstration - that is a very sharp knife!
@Ooh-Rah
I use the western method demonstrated in the video, except that I move the blade in the direction of the cutting edge rather than the back and forth motion. I use my arms more and move my center mass less. In regards to secondary hand placement, I keep my fingertips up near the spine of the blade to avoid getting slurry on my hand and scratching the blade.
 

x SF med

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I use a modified Western technique - a hybrid from the teutelage of Bill Harsey, Wayne Goddard, Chris Reeve and other knife makers who do not send out dull knives, ever...

The issues I have with the video's techniques....
1. he's not using the whole stone, or turning the stone to make sure the slurry is evenly distributed.
2. he is focusing on kitchen knives - this the need for super fine grits to get super fine, long razor edges on the knives
3. A 20* combined angle is steep, too steep for most working edges, while great for kitchen work, it'll chip, dull and possibly fracture under heavy field use - for working knives I use a 28-30* polished edge to mitigate those issues.
4. For people new to sharpening - count your repetitions, exactly for each side of the edge - you can use the sectional technique (one portion of the edge at a time) but have your magnifier ready - you can leave ridges between sharpened sections.
5. He does not show any blade inspection prior to the start of actual steel removal - how does he know where the bad/worst sections of the edge are to plan the sharpening process for that blade?

He does hit on consistency of angle - that is the key item for a consistently sharp edge every time you sharpen - consistency of angle.

Those are the key items I noted, there are others - but remember, he is sharpening very well tended very high quality (Shun-Onion Pro Chef semi-custom hammer hardened Damascus differentially heat treated) kitchen knives, not working/field knives. although these blades are very strong, they have a reduced toughness and hardness from field knives... some terms we'll need to look at. But CPMs30V, CPMs35Vn, D2, ViMax, and other tool/field knife steels sharpen differently and require less fine starting stones than in the video. Most field edges are finished at 5k on a bench strop, not at 10k or higher - there is no need for that fine of an edge in the field in most cases.

@Barbarian - have I missed anything here?

Terms to research for the new sharpeners - as they relate to knife materials / steels
Toughness
Hardness
Strength

@Ooh-Rah - nice find for the video, not nit picking it, just clarifying the differences for different blade applications.
 
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Barbarian

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He briefly touched on the subject of alternating sides to keep the edge even and symmetrical, towards the end of the video. When sharpening field knives this becomes more important. As @x SF med noted, this gentleman is sharpening a chefs knife, and sharpening a field knife will often require the removal of more steel, so greater attention to edge uniformity is pretty helpful.
 

Ooh-Rah

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Gentlemen,

Now that I have a good idea of how to sharpen my Wusthof kitchen knives, can either of you recommend a video/technique to use on my numerous Benchmade and Zero Tolerance knives?

Do I understand correctly that you would not recommend that diamond stone sharpener that I presented in a pic a few pages ago? One thing I noticed with this stone is that they recommend a dry sharpening vs. a wet stone. Would you be willing to recommend a brand/grit level to start with?

Thank you for sharing your experiences and expertise - truth be told I have not really touched a sharpener since this thread has begun and reading through it again, I am glad. Most of my blades are not cheap, I do not want to damage them.

@x SF med @Barbarian
 

x SF med

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@Ooh-Rah -
I believe both Barbarian and I have recommended the Norton Crystolon stones, I think we both think starting with the 600/800 double sided version 3" wide by 8" (min) long x 1.25 inch deep version is a safe bet. Lifting agent should be a quality honing oil or a food/pharmacopia grade mineral oil. BUT, even at the 800 grit level you will need a polishing stone of at least 1000 grit (I use a 1200 grit Japanese water stone then an 800 grit medium on a bench strop) for a truly clean edge.

Buy a cheap knife for initial practice, you won't feel so bad when (not if, but when) you make mistakes.
 

Topkick

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@Barbarian @x SF med (and anyone else who knows a thing or two about knives)

What is the story on Randall knives?

I mentioned in another thread that I am beginning to declutter my life and replace multiple things with "one" of great quality. A friend is selling his NIB Randall #28 Woodsman Knife and I am debating. He is asking $500...(acknowledging the higher price since they sell new for $450 but there is a near 5 year wait)

Thoughts?

This is a Randall #28 Woodsman with a 4.5 inch blade and green Micarta scales.

From Randall's description:
"Drop point hunter blade. Full tang handle construction. 4 1/4″ handle length. Single brass hilt. Green micarta handle material (black micarta available). Border patrol shape. Top of blade notched for thumb placement. Wrist thong with brass ferrule. Sturdy overall construction. Excellent skinning and outdoors knife."

BLADE LENGTH: 4.5"
BLADE STOCK: 3/16” stainless steel
HANDLE SHAPE: Border Patrol
HANDLE MATERIAL: Micarta
HILT STYLE: Standard Single
WEIGHT: 8 oz.

View attachment 16135
Beautiful Knife! Whatever happened with it? I own a Randall model 15. They are truly a great knife with an incredible history. I recently read about Gus Grissom's Randall being found at the bottom of the ocean in the Liberty Bell 7 space capsule after like 40-50 years in excellent condition. There are plenty of cool stories about Randall Knives.
 

Topkick

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That's about what I figured. As our Troll points out, stone, oil and elbow grease.

I do use a sharpening steel from time to time.
My thoughts were that the slicing of that apple didn't show the knife to be very sharp! The video was cool though, I would not have even thought to try something like that....
 

x SF med

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I just ran across this on youtube.

Any thoughts?

No effin way would that Rube Goldberg come near any of my knives, ever. I hope everyone noticed that the temper had already been taken off those blades with a blowtorch, because that friggin pos was going to do it anyway.

you are more than welcome to ruin any of your own expensive sharp pointies however you like, just don't bring them to me for knife doctoring.

I do use a sharpening steel from time to time.
A steel is a fine piece of equipment, especially for kitchen and carving knives. I own them, and use them regularly to hone edges and realign bevels between sharpening/honing sessions.
 

Barbarian

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Notice how the video is prefaced with the disclaimer "for entertainment only". That's the most informative part of the whole show.
 
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