Sharpening Zero Grind

M

MikeH

Joined
Oct 18, 2001
Messages
4,611
I have recently acquired a JSP Bladerigger Arch Angel II, used but in excellent condition and at a very good price, so I can use it guilt-free.
Although it is a real razor at present, it will eventually need sharpening.

This knife has a zero grind, with a fairly high bevel. How do I sharpen this thing and maintain the zero edge?

I am really enamored of this little knife. I can't imagine a more efficient pure slicer. It is very different from my beloved Busses, but will definitely be carried and used.
 
For most of my zero edged users I just lay the entire bevel on a Norton combination stone and sharpen away. Just make sure the entire bevel stays flat on the stone. On something as nice as your knife, you may want to further polish the bevel with some silicon carbide paper glued to a flat surface and just progress up through the grits until your happy as a fine stone does not leave a very nice looking finish. I then just touch the edge up on the fine rods of a Sharpmaker and strop as I find a true zero bevel a little to fragile. This very slight secondary bevel will not even be visible to the naked eye and the trade-off in pure sharpness is minimal. You should be able to maintain the edge quite easily with just stropping. You will be amazed at the edge you can produce I am sure, they cut like hell.
 
Before you let it get too dull, or get involved in actual sharpening, strop it, or even steel it gently. If you lay that bevel flat on a stone, you will scratch it. Do so carefully and evenly and it won't look too bad. But maintain the edge by stropping and you'll avoid a lot of unnecessary work.
 
With a zero grind or scandinavian bevel the entire bevel is sharpened. Typically the bevel is 20-30 degree so putting a secondary bevel woud make it too blunt.
 
Sorry, I need an update. What is a zero bevel? Are you referring to the flat side of a single bevel blade?
 
The Beretta Avenger uses this grind and I always have a problem putting an edge that makes me happy, I can get it razor sharp but when I look with an eye loupe I always see micro chips missing, now I've been told that the diamond hones tend to do this, and being the blade is a VG-10/Carbon Fiber laminate, and with the VG-10 being very brittle/hard i'd be better off using water stones.

I've yet to try it on the EdgePro,(which I assume will solve my problem), but aside from that, zero edge/single bevel chisel grinds are easy to maintain.
 
The only zero grind knife I own is a japanese kitchen knife (deba?) with a polished finish, I use a find waterstone to put the preliminary edge on and a super fine one (15,000 grit) that repolishes the flat after I'm through.
 
mete said:
With a zero grind or scandinavian bevel the entire bevel is sharpened. Typically the bevel is 20-30 degree so putting a secondary bevel woud make it too blunt.
Click to expand...

You are correct in most cases. However, I have a couple knives where the bevel extends over half an inch on a 5/32" thick blade. This produces a very acute bevel and putting a very small secondary (30 degrees included) bevel on it removes any small microchips and polishes with no noticeable loss of cutting performance.

Mike, how wide is the bevel on the JSP blade?
 
Err Zero is not chisel. Zero just means theres no seperate bevel that makes the edge other than the main bevel. (e.g. Pukkos, etc)
 
There seems to be some confusion here. As I understand it "Zero Ground" means no secondary edge/bevel. You can have a Zero Ground Chisel grind it just means there is no secondary edge/bevel. We do up skinning blades with a Zero grind ie the profile is a true "V" from spine to edge. You need to finish the grind with a very very fine stone to ensure the integrity of the edge. A Zero ground Chisel edge would also be possible but you would have to be sure to remove that burr from the flat side. An interpretation of "Zero Ground" may be different over there I would be interested to know.
 
well i have 2 emerson zero bevels, the have only 3 grind angles, vs a chisel grinds w/4, IIRC to sharpen lay the blade flat on a stone and sharpen like a chisel grind knife, then lay the back flat on a stone to flatten out the burr, thats it, easy to do i would think, i never cut anything w/mine so havent had to sharpen, but the emerson zero bevel is as sharp as a scalpel, WAYYY sharper than anything else i have ever seen, period end, nothing else compares! only cons are when ya sharpen it scratches the nice satin finish up, and the edge is kinda thin. but if ya dont mind scratchin it up, it wouldnt be hard to sharpen imho.
 
Most puukkos have fairly acute bevels, ~10 degrees per side. There are some tacticals with puukko style grinds on much thicker stock with much more narrow bevels which are more than twice as obtuse. Some are that obtuse that you could not even apply a secondary bevel with the sharpmaker as it would not even hit the primary let along make a secondary bevel.

As for scratching it while sharpening, why is this a concern. If you are using it enough to blunt it, the grind will get scratched anyway. The most efficient way to sharpen such blade is as Blademan 13 noted, apply a small secondary edge bevel. If this gets too thick that it impairs cutting ability or sharpenability you rehit the primary edge with your coarse stone again to bring it down.

-Cliff
 
Jamie: The Arch Angel blade is 1/8" thick, with a bevel about 5/16" high.
By the law of cosines, I calculate that the angle of the bevel is about 23 degrees inclusive, or 11.5 degrees on one side. Allowing for a little measurement error on my part, the design bevel is probably 20 degrees inclusive.

No wonder the thing slices well!
 
As for scratching it while sharpening, why is this a concern. If you are using it enough to blunt it, the grind will get scratched anyway. The most efficient way to sharpen such blade is as Blademan 13 noted, apply a small secondary edge bevel. If this gets too thick that it impairs cutting ability or sharpenability you rehit the primary edge with your coarse stone again to bring it down.

-Cliff[/QUOTE]

its a concern 'cuz its a $1000 knife lol, i dont carry it for utility, and probably would send to emerson to sharpen it to prevent the scuffs, if it wasnt so high $$ i wouldnt worry about it.
 
You must log in or register to reply here.
Back
Top