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Which grind is better for hard push-cuts (ie. batoning) where edge thickness, strength and toughness are serious considerations?
Before you answer, consider this rendering:
2 knives, both 1/8" thick, 1.25" tall blade (average/typical/common dims).
1st one with a Scandi grind set at 13 degrees (26 inclusive)
2nd one with a Full Flat grind that has an edge thickness of 0.013" around 0.025" behind the edge (sharpened at the typical 30 degrees inclusive). Yes, we would consider this more of a "keen" edge, and not a "beater". But since most bushcraft/survival knife owners tend to gravitate more toward "keen" (while tactical guys prefer "beater"), then I think this is a fair comparison.
Have a look at the 2 knives overlaid in cross section. There is a ton of steel "backing up" the edge on the scandi grind. That equals out to more strength, more stiffness (resistance to lateral torsion forces) and more mass (less vibration/chatter).
Then have a look at the edges zoomed in at 16x. This is all done in CAD and these drawings were done to scale...not just drawn up in Painter.
If you go 0.005" behind the edge of the flat-ground blade, the 2 knives are exactly the same thickness.
So, is it worth giving up stiffness, strength and mass on a difference in thickness so miniscule you need a microscope to see it?
Next time you hear someone say a Flat grind outperforms a Scandi in batoning, point them to this thread.
Is it possible for it to happen? Sure! If you take a Scandi-ground knife with a simple carbon, thin steel (1/16-3/32") grind it too thin at say 10 degrees. Then take a flat ground knife with a heavier edge thickness - say around 0.030", a better quality steel, and a steeper sharpening angle - 40 degrees inclusive. Yes, I agree that you'll see more of a difference in cross section and performance.
BUT....you still give up stiffness, strength and mass.
Personally, I think it has more to do with the way it was used, and less with the grind itself. As with most things...it's most likely operator-error.
I make a knife that matches the 2 profiles above. Same steel, same heat-treat, same blade profile, same handle. One is scandi, one is flat ground.
My testing conclusions are this:
I have video to back this up, I just need to finish editing it.
I'm not saying the Scandi-grind is the only grind to baton with...I just want to put some evidence out on the table for those that are skeptical, unfamiliar, or even saying the Scandi grind is "too thin" or "too delicate" or "too keen" and cannot be used for batoning. It's baffling to me, but every once in a while I'll see someone post this on the forums.
I've put these in the hands of 12/13-year-old boy scouts and let them wail on them. If you ever need a real test (and your blood pressure can handle it), let a young, energetic, non-knife-knut person use your "nicer" knives... and give them free reign. I've done it many times and yes I have cried inside a few times
() watching but have learned some valuable lessons about real-world performance. I have a more experienced and careful hand - from decades of knife ownership, bushcrafting, scouting and knifemaking...any test I do will be "flavored"/biased. But a 12-13 y.o. kid (even my own son)...they tend to push things to the limits and even beyond into abuse at times.
With no skills, no technique, and basic instruction = my scouts have put both the grinds through wood pieces all the way to the bottom over and over again. The scandi lasts longer and it's obvious over time that it works better and has the advantage. (apples-to-apples, all things equal except grinds)
I felt this needed to be said, to give some balance to the hearsay that sometimes trickles down (telephone-game-style) amongst users and buyers of bushcraft and survival gear.
YMMV
Daniel Koster
KosterKnives.com
Before you answer, consider this rendering:
2 knives, both 1/8" thick, 1.25" tall blade (average/typical/common dims).
1st one with a Scandi grind set at 13 degrees (26 inclusive)
2nd one with a Full Flat grind that has an edge thickness of 0.013" around 0.025" behind the edge (sharpened at the typical 30 degrees inclusive). Yes, we would consider this more of a "keen" edge, and not a "beater". But since most bushcraft/survival knife owners tend to gravitate more toward "keen" (while tactical guys prefer "beater"), then I think this is a fair comparison.
Have a look at the 2 knives overlaid in cross section. There is a ton of steel "backing up" the edge on the scandi grind. That equals out to more strength, more stiffness (resistance to lateral torsion forces) and more mass (less vibration/chatter).
Then have a look at the edges zoomed in at 16x. This is all done in CAD and these drawings were done to scale...not just drawn up in Painter.
If you go 0.005" behind the edge of the flat-ground blade, the 2 knives are exactly the same thickness.
So, is it worth giving up stiffness, strength and mass on a difference in thickness so miniscule you need a microscope to see it?
Next time you hear someone say a Flat grind outperforms a Scandi in batoning, point them to this thread.
Is it possible for it to happen? Sure! If you take a Scandi-ground knife with a simple carbon, thin steel (1/16-3/32") grind it too thin at say 10 degrees. Then take a flat ground knife with a heavier edge thickness - say around 0.030", a better quality steel, and a steeper sharpening angle - 40 degrees inclusive. Yes, I agree that you'll see more of a difference in cross section and performance.
BUT....you still give up stiffness, strength and mass.
Personally, I think it has more to do with the way it was used, and less with the grind itself. As with most things...it's most likely operator-error.
I make a knife that matches the 2 profiles above. Same steel, same heat-treat, same blade profile, same handle. One is scandi, one is flat ground.
My testing conclusions are this:
- both knives "get the job done"....*shrug*
- the scandi ground edge tends to last longer
- if you let your wrist "twist" while holding the knife being batoned, you will eventually damage your edge - regardless of grind.
- the flat ground edge enters quicker on the first baton, but the scandi ground edge opens up faster and has less binding throughout the split.
I have video to back this up, I just need to finish editing it.
I'm not saying the Scandi-grind is the only grind to baton with...I just want to put some evidence out on the table for those that are skeptical, unfamiliar, or even saying the Scandi grind is "too thin" or "too delicate" or "too keen" and cannot be used for batoning. It's baffling to me, but every once in a while I'll see someone post this on the forums.
I've put these in the hands of 12/13-year-old boy scouts and let them wail on them. If you ever need a real test (and your blood pressure can handle it), let a young, energetic, non-knife-knut person use your "nicer" knives... and give them free reign. I've done it many times and yes I have cried inside a few times
() watching but have learned some valuable lessons about real-world performance. I have a more experienced and careful hand - from decades of knife ownership, bushcrafting, scouting and knifemaking...any test I do will be "flavored"/biased. But a 12-13 y.o. kid (even my own son)...they tend to push things to the limits and even beyond into abuse at times.With no skills, no technique, and basic instruction = my scouts have put both the grinds through wood pieces all the way to the bottom over and over again. The scandi lasts longer and it's obvious over time that it works better and has the advantage. (apples-to-apples, all things equal except grinds)
I felt this needed to be said, to give some balance to the hearsay that sometimes trickles down (telephone-game-style) amongst users and buyers of bushcraft and survival gear.
YMMV
Daniel Koster
KosterKnives.com
