Buzzbait :
What is it with these v-grind edge bevels?
Jigs and v-rod systems like the Sharpmaker I would imagine are a large influence. However as for v-grinds being poor performers in general, this isn't the case. If you compare a thin Marbles to something like the Cold Steel SRK, then yes you will note a huge difference, but this is not simply due to full conex vs flat with v-ground edge bevels. If you want to see how flat ground knives with secondary edge bevels can behave, find one of Boyes earlier knives, or something from Phil Wilson. Full flat grinds, where the edge is just a hint, the blade is 0.005 to 0.01 (max) behind the edge bevel. In regards to ease of sharpening, this is strongly influenced by the steel. 52100 in particular which Marbles uses is very tough so doesn't chip, and is very easy to machine, so it is quickly honed even by simple abrasives.
I honestly have no idea why a person who actually cuts stuff would not want a full convex grind.
There are advantages to deep hollow grinds for shallow cutting, and the profile is more stable with sharpening. Everytime you sharpen a fully convex ground blade you take metal right off the entire blade, thus it gradually thins out and turns into a very different blade. Knives with secondary edge bevels are more stable, they keep the same general properties, but lose cutting ability with each sharpening, this change of course is very small. It is just a matter of how you want the profile to change over time.
Blades with secondary edge bevels are also in general far easier (in regards to time) to touchup as it just takes a couple of passes on a steel for light alignment, or a couple of passes on a v-rod setup when it is time to hone. Stropping will work for slight use on a full convex grind, but when the blade has been significantly blunted, you can't do anything to match the speed of touching up a secondary bevel and unless you are very carefull to work the primary grind evenly, you are going to introduce a distinct edge bevel anyway.
And of course one of the bigger problems with full convex grinds is that they look like hell after sharpening as you are grinding along the full profile. In the can cutting thread people are concerned about the damage it will do to the blade :
http://www.bladeforums.com/forums/showthread.php?s=&threadid=197598
Specifically :
Andre :
My oldest knife is a
Spyderco Endura with a G2 blade which is now about 13 years old. I once
cut cans and I'm still living with scratches on the sides of the blade.
Those slight marks are nothing compared to what the primary grinds on my fully ground blades look like, some of them have file marks.
When carbon steel is done right, its actually quite stainless.
Carbon steels will rust quite quickly, regardless of finish or heat treatment, however as Cougar noted, actual use is the bane of rust. Your most frequently used knife is going to be free of rust as you are constantly polishing it while cutting. However you will see a patina develop over time. My 52100 MEUK is quite mottled now as are all my carbon blades. But this is only cosmetic so who cares anyway.
In short, I also appreciate full convev grinds, however there are also lots of blades with hollow and flat grinds that are great knives as well, you just have to find a maker than knows how to bring out the best in the profile and match it to the right steel and make sure the whole package is coherently designed around a focused goal.
-Cliff
).
