Factory Edge

Gary W. Graley

Gary W. Graley

“Imagination is more important than knowledge"
Knifemaker / Craftsman / Service Provider
Joined
Mar 2, 1999
Messages
26,365
On my new Benchmade 590 Boost, it's edge is quite toothy, which I like and want to try to maintain that, but, not sure just how to do that as I always head towards a more polished edge bevel.

My guess is to stop at a much lower grit, say 400 and not strop it too much if at all ?

Here's some shots of the edge bevel, you can see the scratch pattern is more perpendicular to the edge, which makes it cut well in either direction of the cut.

BM590-_edge by GaryWGraley, on Flickr
BM590_edge by GaryWGraley, on Flickr

I am also guessing that Benchmade uses belts to put the final edge on their blades, is there any youtube video showing how they do their sharpening?

All in all, I'm still really liking this folder a great deal.

IMG_6655 by GaryWGraley, on Flickr

G2
 
Umm.
Hmmm..
Seriously?

Just stop at a stone that leaves that texture. It looks a bit more coarse than 400, but there is no measurement scale in the pics to be sure. You could try 'dry' (no compound) stropping to mantain/refine it afterwords... just use leather, clean denim, or black and white newsprint on a hard backing to polish the tips of the teeth, but not remove them.
 
Pretty serious ;) reason I asked, but, you did leave some good info, so thanks for that and scale wise it's what arrived on the edge it's about 1 mm wide bevel

The stones I have wouldn't leave that coarse a texture, they are the shapton stones from 320 and up, I have a 120 from Edgepro that I use to help set the initial bevels but even that I do not recall it being as coarse.

G2
 
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Nice pictures Gary, which USB scope are you using? I bought a Opteka 10x macro for the front of my Sony24-55 but I can't see the bir. I've got a class set of some 20x lighted hand scopes in a box in the garage I'm going to have to dig out and try.
With S30v, I thought honing with a light touch using a finer stone would maintain the tooth... But maybe my thinking is dyslexic? This is what I've done with three factory grinds that have obviously been finished with courser grit, because of the toothy feel, and look with the naked eye.
I just honed my new BM940-1501, which I love (considering it a 21st-century traditional pocketknife), for the second time. I am also trying to keep the tooth that came from the factory. I was told the factory is still sending out knives sharpened with a belt (Josh from tech support), so I was expecting more then a few degrees difference between the sides and the hilts and the tips, but found everything to be within 3° on our KME and free iHandy app (calibrated), so I did not bother reprofiling to get it within 1°. I used a DMT 4E Stone both times on the first pass, but followed with the KME 1500 for the second honing. Untreated Levi's has been used for stropping.
I have been simultaneously honing my BM 710-1401, which I also love, to get a feel for the difference between M390 and CPM 20cv, along with a graduation present for one of the grandkids, a BM Hidden Canyon. Beyond the fact that I need to re-profile the S30v from the factory grind, it seems easier to hone than the other two steels.
 
Just a thought, but how about using a medium-to-coarse diamond bench stone and and only moving the blade perpendicularly to the stone working a stroke at a time from one end to the other with a slight overlap. On each run you could vary the starting point and/or overlap to help even things out.
 
Thanks Scott, but didn't use a USB scope, I just used a lens adapter on my ipod touch I picked up here at Amazon it has both a wide angle and close up ability. For the bottom image that was shot with my 'good' camera :)

And ChazzyP I had diamonds a long time ago but I guess I wasn't using them correctly, pressing too hard and pulled the diamonds from the metal, which left just flat metal, so I haven't tried or used diamonds much since but that would probably give a coarse type edge.
G2
 
Gary W. Graley Gary W. Graley
I did the same with my first set of diamonds and wondered why they worked so poorly after a while. With my later sets I learned to let the diamonds do the work.
You could get one of those Ken Onion thingies to mimic factory belt grinds. o_O
 
I need to do better lighting and put the 10x macro on my other glass, as you got the top pic with a 10x on an itouch.
In my mind, I separated the functions of maintaining/Honing and stropping a scary sharp edge, from the need to reestablish the tooth, once the edge is taken back up the bevil enough to lose the tooth... Although, at this point the CPM 20cv does not have as much drag across either honing stone as the m390 (the 710-1401 did get re-beveled as it was secondhand and way off). That's funny, I don't move the knife across the stone anymore... I really appreciate the KME!
 
ChazzyP I do have one of the Ken Onion thingys but the belts I got don't seem to last as well, but I use that mainly for kitchen knives and sharpen my folders by free hand.

And Scott, the adapter thing works pretty good, if I had brought my table top tripod it would have been sharper, as it was it was hand held and that is a crop of the image too.

I've tried several sharpening systems from Lansky to Edgepro to Ken Onion as well as the Spyderco Sharpmaker too, but I have ended up going back to free hand, but I hold the stone in my left hand and knife in my right hand. It works well for me but I do get to a more polished edge.

G2
 
I don't know except to mention that it looks like a "micro bevel" there as well and from what I understand that was done with a buffing wheel. I wonder if you are going to like the performance as well if you only use a stone.

I like the looks (practical aspects of the handle) of the knife.

I say . . . don't resist . . . let that more polished edge form and enjoy it. Heck you can always carry a Silky Saw <<<<link in your other pocket for when you need a saw.
 
Silky saw ;) never heard of that before, interesting! And yes not sure if stones would provide the same type of edge there either, will have to experiment a bit more down that road.
G2
 
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Jimmy, would you share what belts were used on the worksharp? as I'd like to give that a try, I have the extra bladegrinder option which allows a longer belt.

G2
 
I think a coarse DMT (blue) is good way to sharpen and maintain at toothy edge. In my experience it is great for slicing a bit less for push cutting. Will keep slice cutting for a long time, the push cutting ability will deteriorate quicker.
 
Good idea, today during packing up to move, always fun to pack up and move after 34 years at the same place ;) but found two old Fallkniven DC4 pocket stones, one side is diamond the other is ceramic.

So I took the diamond side to my Benchmade Tri-Age and lightly set a micro bevel with that and lightly stropped it on some canvas and found it provided a good toothy edge, once we move, I think I'll invest in a diamond stone.

On the Benchmade Boost, the area where the edge starts has a slight angle up to the edge, I gave that a bit more radius and now it doesn't snag on material when you go to cut, the material rides up and onto the edge without hesitation or catching.

G2
 
Gary W. Graley said:
Jimmy, would you share what belts were used on the worksharp? as I'd like to give that a try, I have the extra bladegrinder option which allows a longer belt.

G2
Click to expand...

Remind me on Tuesday when I get back. I need to verify that.
 
Thanks sir!
G2
 
A Tuesday reminder ;)
G2
 
For the Worksharp we use 120 grit rough cut with a 12,000 grit finish.
 
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