Convex Edges

I'm planning on convexing my 2. I'm mediocre when it comes to sharpening anything though. I'm having it professionally done....well that is the plan......for now
 
I convexed mine and it smoothed out without taking off the black finish. The finish is durable, unless you go at it for a few on 80 grit. I started on 120 then 240, 400, 1500, leather, leather with green compound. It got the job done quick an it made my Bk2 super sharp. I felt like I should have maybe did a 800 grit and after the 1500 go to 2400 grit then stropped.
 
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As you may can see, the edge is a polished convex with very minimal coating damage. I guess I got lucky or did a decent job.
 
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I own a BK-2,11,14 and 16. All of them are convexed by hand using strop with sandpaper and then the strop with black and green compound. Is it easy in the beginning, nope takes awhile to do the initial convex by hand but after all you need is the strop to keep them sharp (unless you chip or ding it). I am a believer in the convex edge, it's the only edge I have used that can take an ass kicking and still want more.
 
I'm about 90% convexed. Lately I've gone to kind of a hybrid thing by convexing then putting a micro bevel on with a stone. Not a lot of stropping anymore. I like a toothier edge than I used to.
 
First time posting here, and I figure this may be a good place to start, rather than starting up my own thread. Since this thread is about convex edges, I'll just assume that a noob like me is welcome to ask questions here. If not, then uh, sorry? Anywho. I've had most of my knives converted to a convex edge because I just find that they hold an edge better than a straight v-grind (if that is the right term). I've always had flat or hollow-ground knives, and I have always wanted a scandi-grind knife just to add to my collection and do a comparison test with them. I picked up a pretty new habilis bushtool not to long ago for $75, and I loved it. Only thing that bugged me, is that it wasn't a true scandi grind. (10 Sherlock points if you know where I'm going with this) So, after dulling the edge quite a bit with wood work, chopping, cutting boxes/paper, I took it to a local knife shop in town and asked the owner to put a true scandi-grind on it. He said no, but he would show me how... Finally... I have been wanting to use that slack belt sander for god only knows how long!! So I set to work. It took an hour or so of careful attention and instruction, but I was able to put a nice v-grind on the entire blade. Then I thought, "Oh what the hell, let's put a convex edge on it." So I move up to the slack part of the belt, and about 30 minutes later, I produce a fairly nice convex edge. It wasn't until I was done putting on the finish that I realized, "Oh %$#!! I hope I can sharpen this the same way on a stone as I do my other knives. So, this brings me to the question I put forth to all of you who are much more knowledgable than me... Am I screwed? I imagine that I could sharpen this much like you would sharpen a very nice katana. The edges in many Japanese swords, as I have read, are convexed. Is there a way that I can sharpen this without a belt, without hours of attention, or, have I screwed the proverbial pooch and am going to have to grind off more metal to bring it back to the v-grind? I'll post pictures if they are needed. I will say, it looks sexy as HELL and is currently sharp enough to scare hairs off arms even after using it to essentially shop, shape, and work work to make a HUGE bonfire.
 
Myrighteye said:
First time posting here, and I figure this may be a good place to start, rather than starting up my own thread. Since this thread is about convex edges, I'll just assume that a noob like me is welcome to ask questions here. If not, then uh, sorry? Anywho. I've had most of my knives converted to a convex edge because I just find that they hold an edge better than a straight v-grind (if that is the right term). I've always had flat or hollow-ground knives, and I have always wanted a scandi-grind knife just to add to my collection and do a comparison test with them. I picked up a pretty new habilis bushtool not to long ago for $75, and I loved it. Only thing that bugged me, is that it wasn't a true scandi grind. (10 Sherlock points if you know where I'm going with this) So, after dulling the edge quite a bit with wood work, chopping, cutting boxes/paper, I took it to a local knife shop in town and asked the owner to put a true scandi-grind on it. He said no, but he would show me how... Finally... I have been wanting to use that slack belt sander for god only knows how long!! So I set to work. It took an hour or so of careful attention and instruction, but I was able to put a nice v-grind on the entire blade. Then I thought, "Oh what the hell, let's put a convex edge on it." So I move up to the slack part of the belt, and about 30 minutes later, I produce a fairly nice convex edge. It wasn't until I was done putting on the finish that I realized, "Oh %$#!! I hope I can sharpen this the same way on a stone as I do my other knives. So, this brings me to the question I put forth to all of you who are much more knowledgable than me... Am I screwed? I imagine that I could sharpen this much like you would sharpen a very nice katana. The edges in many Japanese swords, as I have read, are convexed. Is there a way that I can sharpen this without a belt, without hours of attention, or, have I screwed the proverbial pooch and am going to have to grind off more metal to bring it back to the v-grind? I'll post pictures if they are needed. I will say, it looks sexy as HELL and is currently sharp enough to scare hairs off arms even after using it to essentially shop, shape, and work work to make a HUGE bonfire.
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A lot of people convex their edges by hand using sandpaper and a soft backing like a piece of leather or a mouse pad and use the same method to sharpen them, so I'm sure it would work in your case.
 
You can convex on a flat stone. Check youtube videos by Virtuovice. He uses a water stone, but the principal could easily be applied to any type of flat stone. Keep in mind due to the nature of hand-sharpening any hand-sharpening you do will eventually result in a convexed edge. Good luck sir.

http://www.youtube.com/watch?v=7GsaYsOgHx8
 
Lonewolf01 said:
A lot of people convex their edges by hand using sandpaper and a soft backing like a piece of leather or a mouse pad and use the same method to sharpen them, so I'm sure it would work in your case.
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That's how I did mine. I, like Derek, followed a tutorial by Virtuovice on YouTube in this video. And mine looks like this:

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Now, I just got through watching the video, and am about to start working on my knife. Before I do, I have to say, I keep expecting him to slice in to his index finger the way he is holding the tomato while cutting... Actually kind of wanted to see that happen lol!! Okay, time to work!

Edit:

Since I already had a convex from the belt, it didn't take too long to put an edge back on. I gathered that you need to put some pressure on the blade to get the paper to bend around the blade edge slightly. So, I went with the angle I used on the belt, and seemed to work really well!! Started with 180 grit paper that I had laying around, then moved to 2000 for polishing. Hairs are flying off, and I had to use a broom to sweep up the paper on my carpet... Anywho!! Here is the end result:

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Opinions?
 
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I only have a 7 but I'm tempted to try giving it a convex. The only other time I've really put a lot of work into convexing so far is on my estwing sportsman's hatchet. That took a good amount of time by hand using sandpaper but it does such a better job at chopping now. I'm still happy with my 7 for now; been doing some yard work and the V edge has held up fine so far.
 
All my fixed blades are convexed. It takes really about 15 mins to get a blade from ravaged to razor sharp (or better) with convexing. The smooth transition from the edge to the blade flat makes cutting efficiency much greater.

I don't do this to my folders because I can get a much finer edge because folders I have are fine grained steel that gets a fantastic edge, like VG-10. The carbon steels, generally don't get that level of sharpness, efficiently, for me, by hand...if that makes sense.
 
Myrighteye said:
...Since I already had a convex from the belt, it didn't take too long to put an edge back on. I gathered that you need to put some pressure on the blade to get the paper to bend around the blade edge slightly. So, I went with the angle I used on the belt, and seemed to work really well!! Started with 180 grit paper that I had laying around, then moved to 2000 for polishing. Hairs are flying off, and I had to use a broom to sweep up the paper on my carpet...
Opinions?
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Well, this part right here caught my eye. That is not right at all. I made that mistake, and I was able to get my knife sharp in spite of that mistake but it will not get as sharp as it could if you continue to make that mistake. The reason is that as you sharpen on a material with give, if the sandpaper curls around the edge it will work against you by sanding the apex, which is what you do not want. That is where your edge is, so it is self-defeating to have anything sanding against that.

Looking at your pics, I think you would do better to lighten your pressure, and just increase the angle that you are holding the knife. Eventually you will reach a point where it sounds different, and you will definitely notice it if you are paying attention, and that is where you need to be. Convex is more art than science, but that right there can make things a lot easier for you. If that doesn't work, or maybe even before you try that, cover the edge with black sharpie, then run it across the paper a few times until you see that it is going all the way to the edge. You might need a magnifying glass to see it, but you need to make sure it is going completely to the edge. The only weight you need is the weight of the knife itself, and if you have to add pressure, you are doing something wrong (unless you are sanding off excess material instead of "sharpening"). Just my two cents, but I would try it and see how it works for you.

I thought my knives were very sharp up until the last gathering, and after hanging with Gutsy for a bit I learned that I was close, but not quite where I could be. The key was removing more material from the edge to make it thinner using a flat solid sharpening device (in that case a DMT diamond stone) and then convexing the edge properly. After that bit of work I was able to get the knife someplace I never though I could get an edge.
 
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