Need guidance for sharpening full-convex blades on flat hones

M

maximus83

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Nov 7, 2011
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Does anyone have tips or recommended videos for doing this? Or is this just a bad idea, and I should stick with the mousepad + wet/dry sandpaper method?
 
I have tried this a few times. I can get a good edge- in that sense its not much different than sharpening a v edge. But working the metal behind the edge is difficult to do neatly, in my experience. I was alternating angles every few sharpening strokes, starting under angle and raising the spine until I hit the actual edge angle. This gives a functional convex but its actually a series of small bevels, making kind of a splotchy look. Its no big deal, but not aesthetically pleasing when you're going for a polished edge.

A better technique would be to roll the knife on the convex as its pushed across the stone, which should create a continuous arc and look neater. I tried this briefly but its akward when you're used to keeping a steady angle, so I switched to the other method. Also it would seem to require a segmented approach to sharpening, and I'm accustomed to sweeping the entire edge along the stone. I can do a better job of this on my hatchets, but it's different body mechanics since I take the stone to the blade on those.

Sandpaper works fine if you have all of the appropriate grits. Normally I use a thin peice of leather or suede as a backing. I don't want it to have too much give. You pretty much sharpen as if it were a V-edge, but angle just a hair under to account for the give in the backing.
 
Thanks Robs. So it sounds like you don't go for the approach of trying to put a "micro bevel" on your convexed F1. I've seen some do that, and I assume it works, but if I get a full convex Fallkniven, I want to keep the blade in that form and really have a chance to compare its performance to all the (many) sabre and full-flat grinds that I have.
 
Well, I don't have an F1 unfortunately. My experience is on Opinels and kitchen knives that I have self-convexed. The problem with 'micro-bevelling' is that you are deeping the edge angle. I think the F1 already has a pretty deep angle (compared to something like a Bark River), so it probably doesn't need that from a durability standpoint. Also, if you just keep working that micro bevel you will end up with a relatively thick edge. So sooner or later you have to thin down the convexed blade behind the edge.

Micro-beveling would be the easiest way to field sharpen it, however.
 
The sandpaper&mousepad works like a charm! All you need to add to this kit is a Sharpie to mark the edge and find out if you are @ the right angle!
Full set of waterproof sandpaper(600, ,1000,1200, 1500,2000 and 2500) mousepad&sharpie set me back massive $20,-

Nice extra might be a good strop with green compound(CrO) to finish your edge!
Had a few Fallknivens, and still own a couple of Bark Rivers, and they are shaving sharp:D
Theres a full tutorial found on knivesshipfree.com

Good luck

NvG
 
NvG, after owning both and sharpening both (FK and BRK), did you find the BRK's steel choices and convexed factory grind made the blades easier to sharpen, and more optimal in cutting tasks? If BRK and their current line-up of high-end steels (ranging from non-stainless like A2, or CPM3V, to stainless such as Sandvik, or even S35v) makes a better starting point for working with convex blades, I'd definitely like to hear your thoughts.
 
Put small micro bevel with a stone, it works great, or slowly work whole bevel....practice makes perfect!
 
I truly adore the VG10sandwich steel FK uses! They use a very round convexing(gets thicker faster than the BR), which helps with its splitting capacities. The vg10 is also a lot harder, and will chip sooner(imo)

My personal preference however lies with a more subtle convex edge! This is more prone to damage, but in the BRs A2 steel, these are easy to fix!

I owned a highland river, and micro canadian, and currently own a Canadian Special with black&white ebony handles!
I prefer them to FK, because I can also use them for finer tasks, a if I damage the edge, its an easy fix

Hope this helped, but know I just shared my personal view.....
People can and will agree/disagree as they like
 
Bark River makes Good user knives , I have 2 and they perform well, are easy to sharpen and are much tougher than some tactical bs knives that most pple seem to like!There might be few lemons but the ones I got have superb edge holding!!!Hair whittling in a sec no problem LOL!Fallkniven is very good too, although I like more slight convex......(Moran style grind).I have sharpened these knives on stones, sharpmaker, beltsander , strop and was able to get it to hair whittling sharp most of time! Just practice more thats all!
 
As noted above, its difficult to get a nice polished look across the back bevel. Normally I don't worry about that - its cosmetic after all - but from time to time I'll use some black compound on a leather or newspaper strop and buff it all out. I'll use a Sharpie in reverse - to make sure I'm prettying it up as close as possible to the apex without messing up my edge.
 
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