Sharpening choil

[Gary W. Graley]

Most folks that have been on the forum for a while know of my pet peeve about sharpening choils, if I can get a knife without one I will pick it over one with. The majority of them are made with a crisp 90 degree edge that catches on things and can hang up the knife while cutting at the most inopportune moment and can cause injury in some cases. One knife maker on here that doesn't include sharpening choils retold a story of a cowboy that was trying to cut a rope off of a horse but the choil area hung up on the rope and pulled him off the fence. Myself, while working overseas unwrapping the heavy plastic wrap we put around our machines for shipping, the knife would sometimes hang up if I plunged the blade in too far and the plastic gets caught on the choil. Some people will say, 'don't do that' lol but when you're working to get stuff done, trying to keep the last 1/4" of the blade from going into the material isn't a high priority at the time.

So, one thing that I will do is to soften that choil area down to more of a ramp, so when material does fall into that spot it will ride up and onto the sharp edge. Chris Reeve folders, for the ones I've seen over the years have had an angle in the choil area making it so it doesn't hang up. More makers should take note. It requires a little more time I guess than just drilling a hole or filing the notch, but I think the consumer would appreciate it. Or, as Spyderco knives go, they typically do not have a sharpening choil and that's a great thing to me.

I recently picked up two of the Tactical Pteradactyl knives, a mini Bowie and a medium Raptor, below are the before and after photos of the Raptor. I radiused the sharp edge of the choil into more of a soft curve, now material will move up onto the blade easier than before, without losing very much of the original edge.

Untitled by GaryWGraley, on Flickr

and after a little time on my sharpening stone

Untitled by GaryWGraley, on Flickr

and on my Benchmade Triage folder, I did a similar thing, also I hand ground down the spine into a clip point too

IMG_6424 by GaryWGraley, on Flickr

Benchmade_915_softenstart by GaryWGraley, on Flickr

G2

Edited to add what those new knives look like, these were taken before I radiused the sharpening choil
Untitled by GaryWGraley, on Flickr

Untitled by GaryWGraley, on Flickr

Both are excellent knives, having two now, I think I need to settle on one

 

[eveled]

Good idea to sharpen it like a seration especially if it is too big. The same technique works on chips too. Make it into a serration so it doesn’t catch then sharpen over it. Given time it will disappear.

I can’t stand this

I cut a small choil

Then sharpen it on my diamond plates. Hopefully the choils go away and I’m left with a nice 90*

 

[Gary W. Graley]

On a MasterSmith type fixed blade you will often see than they rounded the area at the choil section, so material will ride up and onto the blade like on this White River version of a Fisk Sendero fixed blade

IMG_8072 by GaryWGraley, on Flickr

Or on this Burt Foster, he has a gentle slope at the start of the edge

IMG_2332 by GaryWGraley, on Flickr

and on my Civivi fixed blade it has a slight curve up to the edge as well

Untitled by GaryWGraley, on Flickr

One way to see how this affects an edge is to try to start cutting on a piece of foam, the abrupt sharp point of the start of the edge would hang up and you can't get it pulled across, where one of the above blades will help by gliding the material up and onto the edge.

G2

 

[SharpBits]

I've long wondered why manufacturers don't make them that way from the start. It's an easy fix, even for me so I'm not going to get worked up over it.
Great post G2, with good pictures to clearly illustrate the issue and the fix.

 

[Crag the Brewer]

You will never see a sharpening choil on one of my knives that I make.
For all the reasons above I hate them.
People have tried to explain their use (need) but I must be stupid, because it just didn't make sense to me......

*I don't like finger choils either..... but I have 1 on one model of mine, but I think it flows better than Most. (so I am a bit of a hypocrite) ;P

In my opinion, Most features on knives are Gimmicks, and unnecessary. Foolish, even.

 

[FortyTwoBlades]

Sharpening choils are only made necessary by people not knowing how to maintain the base of a blade so it doesn't end up recurved. Much like jimping, I consider them a detractor in every case they're present.

 

[Blade Lab]

I'm fine with no sharpening choil IF the edge doesn't terminate at or beyond the plunge grind. Unfortunately, in most cases no-choil knives do run into the plunge, which results in an ugly smile after the first or second sharpening. In that respect I'm pretty much the opposite of Gary: if I see a sharpened plunge grind, I'm running in the opposite direction most of the time.

I know some makers think that a sweeping plunge looks lovely, and it does when the knife is brand new, but it ends up looking like sh*t if the knife is used and sharpened.

 

[Gary W. Graley]

I guess if you have examples that would help understand your bias, but everyone of course is allowed to like what they like and choose what they want. My point stands for me as it is aggravating when a blade is hung up during use. Several cutting demonstrations show that when they are trying to cut and the knife gets caught and when it frees up it can go faster than expected and there is a risk of harm to the user or the blade
G2

 

[Blade Lab]

Unfortunately I don't have any examples handy, because for the most part I don't buy knives like that, and if I do for some reason, I always end up cutting in a choil.

 

[Gary W. Graley]

The point of this thread is to highlight how some choils are made in such a way that it impedes the cutting ability of the knife, and by angling the choil so it is more of a ramp than just an abrupt cut off, it will help overall.
My preference is no choil, which means no lessening of the total edge length too.
G2

 

[Blue Sky]

I prefer to have a small choil, and i’ve been known to add them to knives that I sharpen often. I like to keep the edges of my stones square and I hate that unsharpened bit right at the ricasso. Well, it annoys me at least. And for the record, if I may be a bit immodest, I’m pretty sure I know how to sharpen properly. That said, they can definitely catch on things and rounding off the edge as you show definitely helps.

 

[garry3]

I prefer to have a small choil, and i’ve been known to add them to knives that I sharpen often. I like to keep the edges of my stones square and I hate that unsharpened bit right at the ricasso. Well, it annoys me at least. And for the record, if I may be a bit immodest, I’m pretty sure I know how to sharpen properly. That said, they can definitely catch on things and rounding off the edge as you show definitely helps.

Yep, just enough to clear the edges of my stones and I slightly round the corners of my stones.

 

[Blade Lab]

For the record, I totally get the objection that choils catch in materials you're trying to cut, and I also agree with Gary that CRK does a wonderful job with theirs. I've often wondered why more makers don't emulate them.

 

[DocJekl]

I'm fine with no sharpening choil IF the edge doesn't terminate at or beyond the plunge grind. Unfortunately, in most cases no-choil knives do run into the plunge, which results in an ugly smile after the first or second sharpening. In that respect I'm pretty much the opposite of Gary: if I see a sharpened plunge grind, I'm running in the opposite direction most of the time.

I know some makers think that a sweeping plunge looks lovely, and it does when the knife is brand new, but it ends up looking like sh*t if the knife is used and sharpened.

I guess if you have examples that would help understand your bias, but everyone of course is allowed to like what they like and choose what they want. My point stands for me as it is aggravating when a blade is hung up during use. Several cutting demonstrations show that when they are trying to cut and the knife gets caught and when it frees up it can go faster than expected and there is a risk of harm to the user or the blade
G2

Kinda like the REK Ember gives you a way to sharpen the blade and not hit the plunge grind or ricasso, while avoiding a sharpening choil.

 

[TheOne45]

One knife maker on here that doesn't include sharpening choils retold a story of a cowboy that was trying to cut a rope off of a horse but the choil area hung up on the rope and pulled him off the fence.

Well; I don't ride much (I mean horses) so if the knife has no choil I made it myself.
Here is an example of my Opinel No9:
https://drive.google.com/file/d/11vpaUFwk-vwDSmxXMbGwUx91jP7iL6HQ/view?usp=drivesdk

 

[eveled]

These 2 Buck knives have very different plunge lines. The one on the right has a sweeping grind. Which is why I added the large sharpening choil.

To the point of this thread, I did angle it to help with catching.

I very much prefer the plunge line on the left

EDIT: I found a before picture of the factory 212 edge without the choil.

 

[Blade Lab]

Kinda like the REK Ember gives you a way to sharpen the blade and not hit the plunge grind or ricasso, while avoiding a sharpening choil.

It's a little hard to tell from the pics, but it looks like the plunge terminates juuust before the sharpened edge, so that would be a close but no cigar for me. If he had tightened up the plunge just a tad it would have been perfect.

 

[Blade Lab]

Here's an example of the above: CKF/Rotten EVO 3.0



The red line indicates where the plunge ends. If they had brought it back to the blue line, you could essentially sharpen the knife forever without having the bevel widen out at the heel.

 

[TheOne45]

If they had brought it back to the blue line, you could essentially sharpen the knife forever without having the bevel widen out at the heel.

With free hand sharpening you can compensate and slightly change sharpening angle close to heal, the same like on the tip .

 

[Blade Lab]

With free hand sharpening you can compensate and slightly change sharpening angle close to heal, the same like on the tip .

Yeah, that's a big advantage for freehanding. In this case, I sharpened it on a Tormek, which does allow some finagling of the angle. The edge is actually about 18 dps at the heel, versus 16 dps at the broadest part of the belly. If I had done a consistent 16 dps the disparity in bevel width would be much more evident.