Care and feeding of a convex grind?

F

Foilist

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Dec 20, 2004
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I am about to be the happy owner of a convex-grind knife. Is there a particular way to care for the edge and sharpen it?
 
With a standard V grind, you are sharpening the very edge, so as you sharpen over the years, the V gets wider and wider, making it increasingly difficult to get and keep a fine edge on the knife. With a convex gound blade, you will be taking metal from the entire blade and not just the edge. This keeps the geometry of the blade the same and the knife just as sharp as the day you get it, no matter how often you sharpen or how long you own it.

I've found that W/D sandpaper works great, if the knife actually needs sharpening. A simple stropping on a good piece of leather will probably be all the maintenance you need until you've used the knife extensively.

Here's a site that can help.

Which knife did you order?
 
If leather no longer brings it back, try cardboard. After cardborad, I go to 1200 opencoat WD. It seems very easy.
 
Thanks- good stuff to know. I rarely allow my knives to get truly dull, so stropping sounds like the way.

It's a Bark River Mini Canadian.
 
Foilist said:
Thanks- good stuff to know. I rarely allow my knives to get truly dull, so stropping sounds like the way.

It's a Bark River Mini Canadian.
Click to expand...

Why you lucky dog!! Hats off to ya! (I've got my eye set on a mini-skinner...Ironwood, Big Horn Sheep, or Myrtle wood...all with mosaic pins)
 
Liam Ryan said:
How hard is it to convert a v grind to a convex edge?
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Hey Liam,
Now mind you, I've never done it, but as a woodworker who's sharpened alot of chisels, this is what I'd do....

Start with 320 wet/dry on, say, a mouse pad. I never thought of the mouse pad thing before learning it here, but it sure sounds good. "Strop" the blade, each side, over and over, rolling gently toward the edge (but NOT touching the edge yet until you get rid of the sharp "V" shoulder), until you get close. I wouldn;t use 320 all the way until the convex grind was complete, instead I'd change to 600 to get it even closer (but not all the way final...just barely off the edge). Then 800 to finish the complete curvature down to the edge. Then 1000 and up as final stropping.

Also, while another poster (longbow50) mentioned that you're sharpening the entire blade, I (personally) would not. I would start the grind just above....just barely above... the top of the original "V" grind and gently roll to the edge. Again I say, longbow50 evidently owns a convex ground knife so he surely knows better than I, I'm just saying I wouldn;t roll the grind from the spine to the edge, even though, through time, that may end up being what eventually happens.

I would guess, on a small to medium sized blade, especially starting out with 320 grit or so, the whole process would probably take an hour or two.... or so.

I'll step aside with this advice if it differs from those who know.
You can also go to Bark River and see their instructions on sharpening a convex blade...shaping a "V" grind into a convex edge shouldn;t be radically different. You're just removing much more metal. http://www.barkriverknives.com/home.html
 
StretchNM said:
Hey Liam,
Now mind you, I've never done it, but as a woodworker who's sharpened alot of chisels, this is what I'd do....

Start with 320 wet/dry on, say, a mouse pad. I never thought of the mouse pad thing before learning it here, but it sure sounds good. "Strop" the blade, each side, over and over, rolling gently toward the edge (but NOT touching the edge yet until you get rid of the sharp "V" shoulder), until you get close. I wouldn;t use 320 all the way until the convex grind was complete, instead I'd change to 600 to get it even closer (but not all the way final...just barely off the edge). Then 800 to finish the complete curvature down to the edge. Then 1000 and up as final stropping.

Also, while another poster (longbow50) mentioned that you're sharpening the entire blade, I (personally) would not. I would start the grind just above....just barely above... the top of the original "V" grind and gently roll to the edge. Again I say, longbow50 evidently owns a convex ground knife so he surely knows better than I, I'm just saying I wouldn;t roll the grind from the spine to the edge, even though, through time, that may end up being what eventually happens.

I would guess, on a small to medium sized blade, especially starting out with 320 grit or so, the whole process would probably take an hour or two.... or so.

I'll step aside with this advice if it differs from those who know.
You can also go to Bark River and see their instructions on sharpening a convex blade...shaping a "V" grind into a convex edge shouldn;t be radically different. You're just removing much more metal. http://www.barkriverknives.com/home.html
Click to expand...

StretchNM, I appreciate your input and am pretty much doing what you suggested, on a flat V ground pocket knife, except that I'm thinning the blade some, along with convexing the edge.

The advice that I offered, was based on sharpening a full convex grind, which Foilists newly aquired Mini Canadian will have. :)
 
Good to know Longbow....as I said I didn;t know, I was just surmising how I would do it because I considered tring to convert one of mine while researching the Bark Rivers. I didn;t realize that the Bark River's grind went from spine to edge but, now that you mention it, I do seem to remember seeing the convex grind going straight from the spine. That didn;t occur to me while I was writing the previous post. Are they (convex grinds) really as sharp as they advertise?

I've just now decided....that Mini-Skinner is definitely going to be my next knife.
 
I use this knife at work every nite making anywhere from 100 to 400 x-cuts in cardboard. I also cut plastic shrink wrap and strapping. I work at nite in a grocery store (lots of cardboard) I resharpen with either a EZE-Lap to sided diamond sharpener or the diamond sharpener on my Leatherman Charge. I hold the knife in my weak hand and sharpen away from the edge, rolling off the edge. You can sharpen a convex edge with a flat sharpener.
Scott

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