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Krien regrind on ffg
- Thread starter Kennykid
- Start date
- Joined
- Dec 2, 2005
- Messages
- 71,503
Efficient thread! 
Yeah, it's funny, I always kind of laughed at people when they would say things like "this FFG is ground very thin" or would compare two knives that are both flat ground but one is much thicker and say "this one is much thicker but it's just as thin behind the edge as this FFG blade that's half as thick because it's ground so thin". It never made sense to me, I always thought these people just didn't get the fact that an FFG blade can't have a "thin" or "thick" grind, it just has a grind that's a product of how thick the blade is (at the spine) and how wide the blade is (the distance from the spin to the edge). I always figured it was simple geometry - if you looked at a vivisection of an FFG blade, it's a triangle. So I always thought there was no way to make an FFG "ground thin" - I thought that if you took two blades of a given thickness, the only way one could be thinner than the other is if it was wider and the further the edge got away from the spine, the thinner the edge would be. So when JDavis would say the Spyderco Techno was as thin behind the edge as a Para2 (even thought the Para has a thinner blade), I didn't believe it because a thicker FFG blade means the edge HAS to be more obtuse since the "triangle" is wider (I think I've made my point by now - that used to be how I thought about it).
However, I finally figured it out. Most knife makers don't grind their blade to a zero grind (a zero grind is where the a blade is ground to an apex, so it's actually sharp without having a bevel at all). Before an edge is put on the blade, the knife is quite dull and it could have a 1/32 of an inch (or more, or less) of metal that's flat at the edge separating the two sides of the grind. The same can go for a hollow ground blade. A knife with a thicker blade CAN have a thinner grind than a knife with a much thinner blade as long as it has come substantially closer to achieving an apex on the grind before putting the edge bevel on the knife and sharpening it.
I don't know how close Tom Krien comes to putting a zero edge on his regrinds before he sharpens them. But that's what he does. He leans the edge out and since most full flat ground knives are actually relatively thick at the start of the edge bevel, he could regrind the blade and come closer to apexing the grind at the edge and it would be noticeably thinner. Of course, an edge that's thinner will chip and dull easier, but on most knives, I prefer the best slicing power I can get. The thinner the grind, the better. I have a Shirogorov Hati 95 flipper that has a pretty crazy thin flat ground edge on it and I love that. I keep meaning to pick up the Spyderco Southfork too, because Phil Wilson is apparently the master of extremely thinly ground knives. The Spyderco version is supposed to be crazy thin and yet it's not even close to as thin as his actual custom version ground by him. The Spyderco is still very thin and probably as thin as they could expect any of the knife makers at their factory to be able to grind it.
Aside from being a thinner and better slicer, the advantage of a Krien regrind is also that he can grind it however you want and give you a much nicer grind that's more consistent and very symmetrical. It will look a lot nicer and he can even grind a tanto into a recurve if you want.
However, I finally figured it out. Most knife makers don't grind their blade to a zero grind (a zero grind is where the a blade is ground to an apex, so it's actually sharp without having a bevel at all). Before an edge is put on the blade, the knife is quite dull and it could have a 1/32 of an inch (or more, or less) of metal that's flat at the edge separating the two sides of the grind. The same can go for a hollow ground blade. A knife with a thicker blade CAN have a thinner grind than a knife with a much thinner blade as long as it has come substantially closer to achieving an apex on the grind before putting the edge bevel on the knife and sharpening it.
I don't know how close Tom Krien comes to putting a zero edge on his regrinds before he sharpens them. But that's what he does. He leans the edge out and since most full flat ground knives are actually relatively thick at the start of the edge bevel, he could regrind the blade and come closer to apexing the grind at the edge and it would be noticeably thinner. Of course, an edge that's thinner will chip and dull easier, but on most knives, I prefer the best slicing power I can get. The thinner the grind, the better. I have a Shirogorov Hati 95 flipper that has a pretty crazy thin flat ground edge on it and I love that. I keep meaning to pick up the Spyderco Southfork too, because Phil Wilson is apparently the master of extremely thinly ground knives. The Spyderco version is supposed to be crazy thin and yet it's not even close to as thin as his actual custom version ground by him. The Spyderco is still very thin and probably as thin as they could expect any of the knife makers at their factory to be able to grind it.
Aside from being a thinner and better slicer, the advantage of a Krien regrind is also that he can grind it however you want and give you a much nicer grind that's more consistent and very symmetrical. It will look a lot nicer and he can even grind a tanto into a recurve if you want.
