Nathan the Machinist
KnifeMaker / Machinist / Evil Genius
Moderator
Knifemaker / Craftsman / Service Provider
- Joined
- Feb 13, 2007
- Messages
- 17,529
Someone was asking "what is a reinforced point?"
I'm at the other shop right now and I don't have access to my computer so I'm trying to articulate a complex subject to my phone. We'll see how this goes...
A knife maker, or any design engineer for that matter, has to try to optimize the geometry of their work for its use. A field knife is a general purpose cutting tool intended to cut well in many ways. The Shiv was a dedicated stabbing weapon that was built to tolerate extremely rough use in order to be able to poke holes in walls in addition to people. The Utility Fighter was a Shiv turned into a general purpose utility knife tweaked to work as a fighter.
The Field Knife has good general purpose geometry that is reasonably slicey but won't fail in any kind of halfway reasonable use when relied upon in the field. And after the first few, we started tweaking the grinds and tip a little bit to put additional meat behind the point. But it is fundamentally a full flat grind near the point and the tip will fail if used for heavy prying.
A change to a design to make this sort of knife tolerate prying better would be to drop the shoulders down from the spine to a point better aligned with the tip. That way the center of the blade is behind the point is the strongest part of the blade.
This kind of a diamond shaped cross section is a reinforced point.
you may ask yourself, wouldn't it be stronger still if you didn't cut away the material in the diamond above? The answer is yes, probably. But for that why even cut bevels at all? You could simply sharpen a hardened steel solid bar. The goal is to optimize the geometry for the use. And the fighters have a reinforced point where the meat of the blade is closer to and directly behind that point.
overtime the utility fighters have gotten thinner and the field knives have gotten thicker and we have started leaving more meat behind the point so the difference between the two is less than it once was, but generally speaking the Utility Fighter is going to tolerate stabbing better than the Field Knife and would probably be the better tool for poking a hole in a block wall or soft body armor.
I'm at the other shop right now and I don't have access to my computer so I'm trying to articulate a complex subject to my phone. We'll see how this goes...
A knife maker, or any design engineer for that matter, has to try to optimize the geometry of their work for its use. A field knife is a general purpose cutting tool intended to cut well in many ways. The Shiv was a dedicated stabbing weapon that was built to tolerate extremely rough use in order to be able to poke holes in walls in addition to people. The Utility Fighter was a Shiv turned into a general purpose utility knife tweaked to work as a fighter.
The Field Knife has good general purpose geometry that is reasonably slicey but won't fail in any kind of halfway reasonable use when relied upon in the field. And after the first few, we started tweaking the grinds and tip a little bit to put additional meat behind the point. But it is fundamentally a full flat grind near the point and the tip will fail if used for heavy prying.
A change to a design to make this sort of knife tolerate prying better would be to drop the shoulders down from the spine to a point better aligned with the tip. That way the center of the blade is behind the point is the strongest part of the blade.
This kind of a diamond shaped cross section is a reinforced point.
you may ask yourself, wouldn't it be stronger still if you didn't cut away the material in the diamond above? The answer is yes, probably. But for that why even cut bevels at all? You could simply sharpen a hardened steel solid bar. The goal is to optimize the geometry for the use. And the fighters have a reinforced point where the meat of the blade is closer to and directly behind that point.
overtime the utility fighters have gotten thinner and the field knives have gotten thicker and we have started leaving more meat behind the point so the difference between the two is less than it once was, but generally speaking the Utility Fighter is going to tolerate stabbing better than the Field Knife and would probably be the better tool for poking a hole in a block wall or soft body armor.
I knew I had asked about the reinforced point before. I guess I should’ve just asked simply will you make an Fk with reinforced point like the UF one day. I truly did not mean for the original question to turn to such a long conversation. So again thank you for taking the time to provide all the information 
