Convex Sharpening/Reprofiling???

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knives-n-stuff

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Aug 22, 2010
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Hello, all. I was wondering if you could help me by throwing techniques and/or ideas my way on how to to reprofile a conventional "V-grind" into a convex grind? I'm looking to customise my old Gerber Profile (already added snakewood handles), and all I need now is to put a Convex edge on this puppy :D
I'm going to make it into a potential Bushcraft knife, but I might sell it off after I convex it. The only thing is, I dont have a belt grinder/sander =(

Any help is GREATLY appreciated!!!
 
A fast and simple "apple seed" grind can be done on the slack belt. "Slack Belt" is only a term, and the belt is actually full tension, but the sanding is done on an area of the belt grinder with no platen or wheel under it. Slack belt grinding should be done with a stiffer belt backing belt if you have one on hand. J-Flex belts tend to roll too much, but will work if the pressure is kept light. The acrylic plastic backed micron belts are superb for putting the final edge on, but be careful of the thin edges, as they can cut you like a razor blade when moving at 1000FPS.

Place the blade on the belt with the edge touching and lift the spine until it is barely not touching. This will sand the blade and edge into a convex grind to the edge. Continue , flipping from side to side until you get a good wire edge. Buff off the wire on a paper wheel or use a leather strop charged with rouge or Green chrome. The edge will be a curve with no secondary bevel. If the edge doesn't cut like you want, give it one or two passes across a very fine stone at a low angle. This will put a micro-bevel on the very edge. In re-sharpening, you do this each time. Eventually, after many re-sharpenings, the edge will have thickened enough to be getting too thick to cut well. At that point,you will have to go back to the grinder and re-do the convex grind to remove the extra metal from the edge.
 
Since you don't have access to a belt sander, maybe you would like this. I bought a kit from a website (that I can't remember) for learning to do convex grinds by hand. It had a sanding block that is foam backed, various grits of sand paper, and a couple strips of leather for stropping. I'm sure you could build that kit yourself on amazon pretty easily. Look up the "preppin weapon" by "time shaver tools". You can get it on amazon for a little over $20, and you can pick up the sand paper anywhere (if you don't already have it).

Also Google "Mouse pad convex sharpening". It's pretty much the same concept as the sanding block I mentioned. There should be a bunch of articles and YouTube videos showing technique. It's definitely not going to be as fast as a belt sander, but it will get the job done.
 
Thanks... I'll look into it. I might just start with very course sandpaper, and then work my way up to a strop. It'll take a while, but It will be well worth it.
:D
 
Sorry, I missed that part.

Use a wooden backing block and hand sand as with a flat grind, but turn the block toward the edge as the stroke nears the edge. This will sand a curve. When the rough shaping is done, glue a mouse pad to a block of wood, and place the paper on it. Use this padded block to sand/polish the curved surface from 400 up..
 
bladsmth said:
Sorry, I missed that part.

Use a wooden backing block and hand sand as with a flat grind, but turn the block toward the edge as the stroke nears the edge. This will sand a curve. When the rough shaping is done, glue a mouse pad to a block of wood, and place the paper on it. Use this padded block to sand/polish the curved surface from 400 up..
Click to expand...

Thanks, Bladsmth!!! I think I'll try this tommorow.
Thanks fior the info! :D


Best Regards, Jared (future Knifemaker???) :rolleyes:
 
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