Convexing an Edge

Go to youtube.com, and in the search box type in " how to convex sharpen a knife" and you'll have a bunch of goodies pop up.
 
Thanks guys.

I was sure that the answer was stropping. I guess I flunked this quiz. I'm scared to do it on the knives I have right now though darnnit!
 
cziv said:
Thanks guys.

I was sure that the answer was stropping. I guess I flunked this quiz. I'm scared to do it on the knives I have right now though darnnit!
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Stropping would do it, slowly. The sandpaper/mousepad method is like stropping, only much faster. Finish with stropping for a polished, very sharp edge.
 
Thanks guys,

I watched somebody (not sure who), use a mousepad and sandpaper. Piece of cake

I was already a good stropper but the lightbulb in my head went on when I realized that using the sandpaper strop method would knock those bevels into a convex - quick!

I used the mousepad next to me and took a very sharp knife with two bevels (30* over 20*) and stropped it on 400 grit for about 15 strokes per side then 600 for another dozen or so and then piece of finer (not sure what - a fragement w/o a number).

Took it to a strop loaded with that green compund next and my new blade shows up like a mirror under a very weak magnifying glass and is beautiful.

It was very easy - too easy. Thank you all! :D
 
cziv said:
Thanks guys,

It was very easy - too easy.
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This is pretty much what I said once I figured out how to get my knives sharp for about $20 in materials and a few hours getting the technique down.

All my knives are now convex. I suspect this will eventually bite me in the ass, but so far it's working beautifully.
 
Now knowing how easy and cheap convex sharpening blades can be I'm going to have to get into it. Thanks for the links and direction.
 
another way if you have a gatco or lansky system is to start at the steepest angle, lets say 30 degrees, get it sharp, then with the same grit, do 25, then 20 then 17. move to the next grit in line and repeat. You may not go as low as 17 degrees or start as steep as 30, depends on how thick the blade is. Once you get all the way though with your finest grit, strop with some black compound on soft leather (NOT HARD LEATHER) laying the blade down at the shallowest angle you used. This will blend the edge together and get you a seamless apple seed / bullet shape convex.

but yeah sandpaper is the easiest way.
 
Jack Shen,

Is that the right order of things? I thought it was opposite. moste acute bevel firs, then wider microbevels, the blend them with stropping (for hard steel) snadpaper then the soft leather on a stop paddle or block.

Also I was old that convexing knives that were by nature, thin as in most Spyderco or Benchmade knives is a waste of time. I was told you need a thick spine like RAT Cutlery blades or a some Cold Steel thick blades like the Master hunter.

BluntTruth his YT name not forum name has a two part video on convexing which is worth watching http://www.youtube.com/watch?v=aGPcwHdRRJ0 that tnt-user posted above.

I've seen him before but it's quite good and worth a watch.

His diagrams are what I'm referring to above.
 
You can still convex a thin blade. You still get the advantage of ease of sharpening. I'm still not sold on the idea of convex edges being stronger than V edges anyway, at least not if they have the same terminus angle. However, like I wrote earlier, you don't have to be as fussy with your angles, and you can get a screaming sharp, highly polished and durable edge, with minimal effort.
 
@cziv

You can go either way for that, it's personal preference. For me the steepest to lowest is easier, since I can feel that the edge has been established, and the rest of the steps are just to get rid of the "ledge" on the 'V' made by grinding the edge on. When I go from lowest to steepest, it's easy to make the mistake of grinding too much off and just ending up with a 30 degree regular 'V' type grind.

You may want to experiment with a really cheap knife and see which way works best for you, as long as you get that bullet / apple seed shaped profile at the end, it really doesn't matter too much how you got there :)

hope that helps
 
I have found that after I get an edge properly profiled on a stone I can maintain it regularly with the (400 - 600) sandpaper/mousepad method and a few final swipes on the leather strop.
 
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