Scary Sharp NO Once Again

[Lenny]

Well, I finally took the NO out back and gave it some hard use. That sucker chops like crazy. Unfortunately, I was chopping up the frame of a boxspring and nailed a nail really hard. After I was done, I looked at the edge under a 10X loupe, Yep, there was a small chip there, not just rolled over. So I tried my grooved steel on the flat edge, no luck. Then tried some light strokes into the blade on the fine rod of my Spyderco sharpmaker. This was enough to raise a fine burr on the concave side. I then tried to strop the burr off, no luck. I then tried other various methods to remove the burr, no luck.
Finally, I got frustrated and took out the Lansky. It took a while to change the concave side to a V, but I finally got it. I put an angle of 25 degrees on the edge, then finished off with a strop. Man, that edge scares the heck out of me now. The hairs on my arm jump off my skin when they see the edge coming. I know, I know, I've probably compromised edge holding and chopping prowess some, but I plan to use this blade more for cutting than chopping. And I now know that I can get that hair popping edge back whenever I need to.
Comments? Has anyone else done this to their blade? How's the edge hold up?
Please keep the flames for altering Jerry's edge to a medium high setting.
Lenny

 

[Johan]

Don't sweat it Lenny, I've got 4 Busses and I've taken the convex edge off of two (#5 and #7) because of frustration with getting a satisfactory edge after sharpening. However, when I got my two new Busses (BM and NO) I decided I'd do my best to keep the convex edge.

Several months ago I had a long converstaion with Jerry about the problems I had encountered sharpening the convex edges. He informed me that one of the characteristics of INFI steel is that it forms a micro-burr during sharpening that is highly flexible. In other words, it tends to flip flop from side to side rather than break off. It was his opionin that it was the presence of this burr that was preventing me from attaining the edge I was looking for. His suggestion was stropping. Lot's of it.

When I received my BM and NO I found that the NO was quite sharp, but the BM was not, in fact in had great difficulty not ripping up paper when trying to make a cut. This didn't bother me because there's not a knife that I own that doesn't get re-sharpened the minute it gets in my hands. Blame it on the EdgePro sharpener I have (www.gorge.net/business/edgepro)

There have been many threads about how to sharpen a Busse: ceramic sticks, foam backed sandpaper, both sides on a stone, and stropping only. I've tried all of them but the method I used most recently gave me the best results with the least hassle. The tools I used were an EdgePro Apex and a leather strop (one of my own, a section of walnut with a strip of high-grade smooth leather attached, loaded with a grean stropping compound from Lee Valley Tools).

I began by sharpening the flat side with a 100 grit stone at 24 degrees (the same as the factory angle). I worked the flat side until I had a fine but even burr along the convex side. I then took the stone and (free-hand) lightly stroked the edge of the convex side to remove the burr. I did not work it hard enough to put a burr on the flat side, just enough to knock it off. I repeated this process until I reached my final grit (I originally went to 600, but found I had better resutls at 320). Once I had finished with the stones I began to work the convex side with the strop. Working only the convex side until I could not longer feel any burr and then alternating sides.

The result was a blade that could slice through 1/2" manilla rope in one stroke and yet would push cut through ordinary paper. If on thinks about it, the fact that one is getting a blade that is 1/4" thick with a 24 degree angle to push cut at all is quite amazing.

Anyway, this method of sharpening definetely produced the best results for me with the least amount of hair pulling and swearing. I hope this is of some help to you.

 

[Lenny]

Thanks Johan,
I guess I gave up on the stropping too soon.
How do the edges on your Basics hold up compared to the double edge? Do they still chop well? I'm wondering if I should some day send my NO back to Jerry to put the original edge back on.
Stay sharp,
Lenny

 

[Johan]

To be honest Lenny, while understanding and agreeing with the physics that make the asymetrical edge stronger, I didn't notice any decrease in edge holding ability or strength. In fact, most people seem to think the V grind feels sharper than the asymetrical.

 

[Lenny]

Well, maybe it's like this:
Perhaps the assymetrical edge is stronger than the V grind edge (slightly). But, it could be that the INFI is so superior to other steels, it's still stronger as a V grind than any of us will ever need. My only concern was ease of sharpening. For my limited talents, sharpening a V edge is simple on something like a Lansky or Edge pro.
Does anyone else have experience with V-grinding a Busse?
Lenny

 

[Cliff Stamp]

How the blade chopping performance is effected, depends on how acute the bevel you put on was compared to the convex one that was there. If your flat bevel went from the shoulder of the convex bevel to the already existing edge, then the new edge would be more acute and would in fact chop better than the old one, it would also in general cut better. The disadvantages are that it is weaker and will take more damage in regards to impacts and will roll faster.

The primary reason for the dual edge is to allow sharpening via the flat bevel, but retaining some strength of a convex one. If you are having problems sharpening then it loses its main advantage. However I would go with a full convex grind as opposed to a full flat one. But then if you are having problems sharpening the dual edge, a convex one is maybe not going to be the one you want.

In any case, the dual edge is not the deciding factor in the performance of the Busse Combat blades. It is a nice idea with some functional advantages, but if you put a dual edge on a 10" 1095 bowie, you don't have anything close to a Battle Mistress.

How durable the edge is will depend on how you use it and how much force you exert on the blade when you are typically doing whatever that is. You alone of course can determine this. I would not be concerned about changing the edge bevel. At worst you will find that it is not as durable as you would like so you just change it once more. You might have to repeat this process several times to find the optimal edge geometry - but the positive thing is that once you go through it with one knife, you can do it much quicker with your next one.

-Cliff

 

[Hoodoo]

I've reprofiled the edges on both my Badger Attack and Mean Street. It works for me.

Don't sweat the small stuff. Just have fun! The chopping police won't come get ya. Yet...

------------------
Hoodoo

I get some pleasure from finding a relentlessly peaceful use for a combative looking knife.
JKM

 

[Lenny]

Youz guys is da best!
Good, sound, practical advice is always appreciated.
I absolutely love this knife. I figure I can go into the woods with it, my Leatherman Wave in the pouch, and some assorted survival stuff in my pockets, and live very nicely for a while.
Thanks again.
Lenny