The "Ask Nathan a question" thread

Nathan the Machinist Nathan the Machinist do you have a preference when it comes to steel for the HDFK? I understand D3V will be the king of toughness but are there any advantages to having D2 in that pattern?

Well that's a good question.

The HDFK is intended to be a versatile knife, so it stands to reason you might get it in different flavors depending on your intended use. But, that said, no D2 is probably not a great fit for it for most people (which is why we're using a variation of D2 for this)

Here's my reasoning. You might love the high performance engine in your favorite motorcycle, but it would suck if it were put in your pickup truck because its HP:Lbs ratio becomes pointless and it lacks torque. Wrong set of properties for the application.

As much as I like old school D2, it shines in applications where I would simply chose a different knife. D2 at high hardness, an optimized HT and a thin blade is a great cutter with very good edge retention. Its weakness is lower gross toughness and a slightly chippy edge which causes edge stability issues in rough use. <--- Thus it's not a perfect fit for the HDFK which was intended to be a general purpose heavy duty knife that can be used (abused?) hard with impunity. Actually, I think INFI would be a pretty good fit for this pattern for folks who want a little more gross toughness with similar stain resistance and edge stability and are okay with a little lower edge retention. I even asked Jerry about it, and he was super nice, but I don't think he was real keen on the idea...

So, all that said, I chose PSF27 for the D2 for this blade. They claim it's about twice as tough as regular D2 (on paper) and has fewer issues with micro chipping and makes a good D2 alternative for a larger hard use knife. I'm calling the PSF27 a "D2" because technically it is. The alloy is the same. It occupies a realm between CPM and conventional melt. I don't particularly like CPM D2 and usually go for their conventional melt, because I think they threw the baby out with the bath water when they made it a PM steel. I'm hoping PSF27 can be a good in between compromise.

I think the PSF27 D2 HDFK will be a good fit for folks who don't need the extremely high toughness of Delta 3V and want more abrasion resistance for longer edge retention in abrasive materials like hide and dirty vegetation etc.

It's a nitch application for touched-in-the-head knife nuts. It does have the advantage of being a little more affordable than Delta 3V and I'll leave the bark on the sides (some people were asking for that). It is just some prototypes. They won't even be marked.
 
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kinda curious about D2 for this knife, wonder how it'll perform in the shrubberies
 
Actually, I think INFI would be a pretty good fit for this pattern for folks who want a little more gross toughness with similar stain resistance and edge stability and are okay with a little lower edge retention. I even asked Jerry about it, and he was super nice, but I don't think he was real keen on the idea...
I think the HDFK would have also
Well that's a good question.

The HDFK is intended to be a versatile knife, so it stands to reason you might get it in different flavors depending on your intended use. But, that said, no D2 is probably not a great fit for it for most people (which is why we're using a variation of D2 for this)

Here's my reasoning. You might love the high performance engine in your favorite motorcycle, but it would suck if it were put in your pickup truck because its HP:Lbs ratio becomes pointless and it lacks torque. Wrong set of properties for the application.

As much as I like old school D2, it shines in applications where I would simply chose a different knife. D2 at high hardness, an optimized HT and a thin blade is a great cutter with very good edge retention. Its weakness is lower gross toughness and a slightly chippy edge which causes edge stability issues in rough use. <--- Thus it's not a perfect fit for the HDFK which was intended to be a general purpose heavy duty knife that can be used (abused?) hard with impunity. Actually, I think INFI would be a pretty good fit for this pattern for folks who want a little more gross toughness with similar stain resistance and edge stability and are okay with a little lower edge retention. I even asked Jerry about it, and he was super nice, but I don't think he was real keen on the idea...

So, all that said, I chose PSF27 for the D2 for this blade. They claim it's about twice as tough as regular D2 (on paper) and has fewer issues with micro chipping and makes a good D2 alternative for a larger hard use knife. I'm calling the PSF27 a "D2" because technically it is. The alloy is the same. It occupies a realm between CPM and conventional melt. I don't particularly like CPM D2 and usually go for their conventional melt, because I think they threw the baby out with the bath water when they made it a PM steel. I'm hoping PSF27 can be a good in between compromise.

I think the PSF27 D2 HDFK will be a good fit for folks who don't need the extremely high toughness of Delta 3V and want more abrasion resistance for longer edge retention in abrasive materials like hide and dirty vegetation etc.

It's a nitch application for touched-in-the-head knife nuts. It does have the advantage of being a little more affordable than Delta 3V and I'll leave the bark on the sides (some people were asking for that). It is just some prototypes. They won't even be marked.
The HDFK in D3V is going to be Outstanding! I would however also buy a couple in INFI:);):thumbsup:
 
Actually, I think INFI would be a pretty good fit for this pattern for folks who want a little more gross toughness with similar stain resistance and edge stability and are okay with a little lower edge retention. I even asked Jerry about it, and he was super nice, but I don't think he was real keen on the idea...

One day you two are going to have a knife baby and it will be glorious.
 
That would be me! Bark on the side. excellent I would use it primarily for cutting. So I would love one of the protos for testing on meat, and various cutting chores. But I do also NEED a D3v version. Life is full of needs. sigh.


I think the PSF27 D2 HDFK will be a good fit for folks who don't need the extremely high toughness of Delta 3V and want more abrasion resistance for longer edge retention in abrasive materials like hide and dirty vegetation etc.

It's a nitch application for touched-in-the-head knife nuts. It does have the advantage of being a little more affordable than Delta 3V and I'll leave the bark on the sides (some people were asking for that). It is just some prototypes. They won't even be marked.
 
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That would be me! Bark on the side. excellent I would use it primarily for cutting. So I would love one of the protos for testing on meat, and various cutting chores. But I do also NEED a 3 version. Life is full of needs. sigh.

I'll try to get you an Optimized D2. You just moved ahead of Grog because the optimized D2 is just so, well, You :D
 
Nathan, know you are busy with the HDFK pre-orders, but have you given any thought as to what might be your next offering-Build? Know you had mentioned the Competition Chopper Collaboration with Dan was in the works and might be available by the end of the year. Just was wondering if your tentative schedule of upcoming offering's has changed? Thanks :cool:;)o_O
 
Nathan, know you are busy with the HDFK pre-orders, but have you given any thought as to what might be your next offering-Build? Know you had mentioned the Competition Chopper Collaboration with Dan was in the works and might be available by the end of the year. Just was wondering if your tentative schedule of upcoming offering's has changed? Thanks :cool:;)o_O


D2 HDFK ~ 24
D3V HDFK ~160 (mostly for preorder)
BC ~ 10
MC ~ 50
LC in 4V ~24
EDC in D3V ~175
Competition cutter ~???

^ basically in that order. All of those are in process now in one stage or another.

We're doing the final grinding, finishing and sharpening on the last 10 LC preorder now (should be totally finished in two weeks), the HDFK finished on the pig today and is over half done on the Mori (80 went to Peter's today), we started setup on the MC on the pig today, we're starting cutting material for the EDC tomorrow (will start on Romi in one week), there are 4V LC and D3V BC machined and awaiting grinding and HT. The competition cutter and a one-off custom project (an integral) are both in the design phase now, everything else material is here and at some point in the process.


edit to add: we're sawing up a bunch of antique micarta (edge grain) for the HDFK order now and will start laminating it to black micarta liner next week. Our big horizontal bandsaw looks like a huge blob of brown shmoo right now.
 
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D2 HDFK ~ 24
D3V HDFK ~160 (mostly for preorder)
BC ~ 10
MC ~ 50
LC in 4V ~24
EDC in D3V ~175
Competition cutter ~???

^ basically in that order.

The competition cutter and a one-off custom project (an integral) are both in the design phase now, everything else material is here and at some point in the process.

That's a lot of work for a couple people. Sounds like long days and short weekends. Glad to see you take some time off from time to time.
 
D2 HDFK ~ 24
D3V HDFK ~160 (mostly for preorder)
BC ~ 10
MC ~ 50
LC in 4V ~24
EDC in D3V ~175
Competition cutter ~???

^ basically in that order. All of those are in process now in one stage or another.

We're doing the final grinding, finishing and sharpening on the last 10 LC preorder now (should be totally finished in two weeks), the HDFK finished on the pig today and is over half done on the Mori (80 went to Peter's today), we started setup on the MC on the pig today, we're starting cutting material for the EDC tomorrow (will start on Romi in one week), there are 4V LC and D3V BC machined and awaiting grinding and HT. The competition cutter and a one-off custom project (an integral) are both in the design phase now, everything else material is here and at some point in the process.


edit to add: we're sawing up a bunch of antique micarta (edge grain) for the HDFK order now and will start laminating it to black micarta liner next week. Our big horizontal bandsaw looks like a huge blob of brown shmoo right now.
That's a lot of knives in ~4 months time. If you can get it done I will be seriously impressed. Make sure to take a break every now and again so all three of you can pat each other on the back "well done" :thumbsup:
 
Having 'contracted' with other makers for 10+ blade orders ranging in the thousands of $,$$$, I do have to say that one distinguishing factor I've grown to respect from CPK is not only the precision in craftsmanship, but also in process, i.e., the discipline to appropriately manage timelines, projects and the 'say-do' ratio. That's a really difficult line for some makers to walk, but appears in check with CPK, which is a testament to all-around good business and practice.
 
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