Home Forums Gear Knives and Blades frustrated at not getting a razor sharp edge

frustrated at not getting a razor sharp edge

about 6 years ago I was at bass pro shops and they had a sale on knives,so I picked up two non-serrated blade marine combat knives for future use , they are genuine K-bar not clones and if I remember correctly I paid about $70 each at the time, they got put away in my safe until about a week ago when I pulled one out and decided to sharpen it , now I can put a razor edge on almost every knife I own, and some of my san-mi cold steel knives can take an exceptional edge, but after 3 -4 hours of careful hone with a diamond hone the K-bar has an edge that I would call barely acceptable while even some of my gerbers, old timer and sharade knives, that cost far less have far better results in far less time?


and the same sharpening process has consistently resulted
in excellent results on the other blades?
is it just that the steel is soft?
any suggestions?

Is your edge worse,than out of the box ?

The grind is probably thick at or right behind the edge. Many times,this is the problem

no! its now better, than it was as it came out of the box/wrapper, but its still not up to the standards I can generally get on a good piece of steel to produce a true shaving sharp edge

That blade is ground thick so idiots won't chip it doing stupid SURVIVAL tests with it. It will need reprofiling before it will take a really good edge. That said, it should still get sharp enough to scrape hair. Try to get it sharp enough to catch on a fingernail with stones, then strop it away from the edge on brown box cardboard.

With thick blades I either do a convex edge or make two angles on the edge so that when I work the final edge I'm not trying to take material off a very wide edge which takes forever and never really works.

With thick blades I either do a convex edge or make two angles on the edge so that when I work the final edge I'm not trying to take material off a very wide edge which takes forever and never really works.r

Page down in this link to the edge picture
[img]http://www.tameshigiri.ca/2014/01/07/razor-edged-how-sharp-is-sharp/[/img]

more and more often these days, I opt for a convex edge. I am working on a D/P (Doug Dart) custom now. Never did like the edge profile, and it's going to be a convex now.

I too like a convex edge. My favorite is a convex to a zero edge with no secondary angle.

When reprofiling an edge the convex is probably the easiest and fastest to do for me if working off a grinder. It's also the easiest to touch up sharpen. Most factory edges however are either flat ground with a secondary edge or hollow ground because they can be done on a machine. IMHO most factory edges are too thick because they have to be idiot proof. Otherwise everyone who wanted to baton with a small folder or cut wire would wound up trying to get the factory to replace an edge.

Soft steel and you have edge geometry working against you....

I have seen knives marked K-bar that are knock offs with ???? steel, etc.
Hopefully yours is the real thing.
Geometry, heat treat and consistent angle during sharpening are important.
jmho
Tim

Still, make sure you are raising a burr.

add
Good point that I should have mentioned. Senior moment.

luckily I have an older lo-ray power belt system to rebevel these knives bought with a pry bar edge. rebeveling that needs lots of material removed is a major task w/o power equipment.cranky72