The "Ask Nathan a Question" Thread

" Nathan "

I saw the mention of the HDFK in D2. Just curious about how A2 steel would be in that design ? Just curious , seems the more I hang out here the more I want to know about steel differences and use.
Thanks :-)
 
duramax said:
" Nathan "

I saw the mention of the HDFK in D2. Just curious about how A2 steel would be in that design ? Just curious , seems the more I hang out here the more I want to know about steel differences and use.
Thanks :)
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A2 would do very well in that design (it's an ideal application for that alloy), but it would be redundant. I like A2, but optimized 3V has similar edge stability and edge retention and greater toughness and stain resistance. There is too much overlap in their properties to do both, and D3V is probably better in every meaningful way for the application.
 
Nathan the Machinist said:
A2 would do very well in that design (it's an ideal application for that alloy), but it would be redundant. I like A2, but optimized 3V has similar edge stability and edge retention and greater toughness and stain resistance. There is too much overlap in their properties to do both, and D3V is probably better in every meaningful way for the application.
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Thank you, I thought A2 was pretty good stuff :thumbsup: Thought it might be easier to machine making it more cost friendly. But with your explanation on D3v and all that's been said about D3v. Well it makes sense that with your D3v that it would come out on top. The D3v is great stuff :-) :-)
Thanks
 
I'm curious, and I hope this hasn't been mentioned before. You say the new knife in optimized d2 is actually PSF27? Are the optimized d2 edc's PSF27 as well?


It seems that steel is gaining some real popularity. I have a slicer from big Chris in that steel and its unreal in performance.
 
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LukeTheSpook said:
I'm curious, and I hope this hasn't been mentioned before. You say the new knife in optimized d2 is actually PSF27? Are the optimized d2 edc's PSF27 as well?

It seems that steel is gaining some real popularity. I have a slicer from big Chris in that steel and its unreal in performance.
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The EDCs are conventional melt Crucible D2. IMO this is a better steel with better edge retention and particular cutting characteristics in soft abrasive materials like hide that makes it ideal in something like a skinning knife etc. But it lacks the toughness required for a large knife intended for rough use like the HDFK. I wanted to try a D2 for this pattern but CPM D2 doesn't perform for me, so we tried PSF27 for a nice "middle of the road" alternative.


With D2, the heat treat is very critical and it deviates from the industry standard HT developed for tooling considerably. Most people who have used D2 in a knife haven't seen what it is actually capable of, it is truly a high performance material. It isn't stainless and it doesn't have great toughness nor fine edge stability so it doesn't always test as well as super steels in particular testing that looks at joules of energy absorbed in a fracture impact test, catra knife abrasive media testing, and rough use demonstrations in things like nails etc. But, with an optimized heat treat that addresses some of the underlying fine edge stability issues it is both tougher and has better real wold edge retention than most super steels in real world use and will run circles around most materials that most people have experience with, when used normally as a knife. Despite not being particularly popular, nor commonly done "right" it has enormous real world performance potential in a working knife and is one of my favorite materials. PSF27 is a modern variation of D2 that has the toughness needed for a heavy duty field knife, we're trying it out in some Heavy Duty Field Knife prototypes with the goal of achieving some of that D2 goodness in a big knife.
 
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^^^ I love it when he talks dirty about edge stability!

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I may be a lowly welder but I can say this, I use the HELL out of my knives and this EDC in D2 just keeps going. It loses its shaving sharpness after a little bit (like anything will) but it keeps what I call a working edge for a long, long time. I end up running it on a strop about once a week but it'll cut and cut and cut for quite a while even when it doesn't have that "sticky" sharp feeling that grabs your finger and doesn't shave arm hair.
 
I wonder if that bad mother*^(k3r prototype could be reground as a recurve to work out those 'little edge/microchips' back to a working blade. I know it is a historical piece as much as anything and I know you value it as such, Bob. Just wondering out loud (random thought?). My brain is always 'tinkering' and wondering if it could be modified. Not a serious question.
 
TRfromMT said:
I wonder if that bad mother*^(k3r prototype could be reground as a recurve to work out those 'little edge/microchips' back to a working blade. I know it is a historical piece as much as anything and I know you value it as such, Bob. Just wondering out loud (random thought?). My brain is always 'tinkering' and wondering if it could be modified. Not a serious question.
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Blasphemy.
 
I should put a shot together of them all, which I haven't done yet. Hell, I can't even find the above pic in my computer or fototime album since I synched it to google, lol. But I'll put one together tomorrow.

Edit: at least I found the above 2-knife pic finally
 
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Wow Bob, that pic really puts the BC into perspective. And the HDFK comes out looking just awesome in size. I can't see how that isn't going to be massively popular.

Thanks for takin' the time to take that pic and sharing.
 
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