Spyderco Forums

Ogre wrote: ↑

Sun Mar 05, 2023 8:36 pm

Hawaii808 wrote: ↑

Fri Nov 18, 2022 2:39 pm

What angle to sharpen at do you guys think will be good for the m398?

I too am wondering what a good edge angle for this steel would be. I'm seeing another brand put a 14° edge on CPM-S90V and CPM-154. With M398 being high on edge retention but low on toughness, would a 15° or 17° be prone to chipping? Or, should I opt for a 25°ish? I'm thinking this will be, primarily, my bird and trout... (and cardboard) knife.

Get on real computer, go to You Tube, and watch edge "Stability" routines this man does. Some supposedly low toughness steels really do hold up very well at the edge. Any site on a phone is about 1/4 as good as a site on a real computer. The code for the phone and the mobile site it directs you to are "light" so any phone can display the short form content. You buy the phone with the whiz bang processor, but the processor gets fed bread and water.

https://www.youtube.com/@FearNoSteel

The toughness test takes a bar of metal, supports it on both ends and then slams a weight into the middle to break it. A long standing metal test. However, it is more about a bulk property when you use the metal to make tooling. Edge stability is a product of the elastic strength of the steel where it deforms and pops back like a spring. And the ultimate strength of a steel where it is actually breaks. Many steels have properties that allow it to bend past springing back a long way before it breaks reaching ultimate strength. On the edge your failure may just be a roll in the edge, plastic deformation, or a loss of a piece of edge, ultimate failure.

The M398 Mule has been tested and the HRC is around 64. That from my research is what people have had custom knife makers provide in M398 as a sweet spot. At 62 it lacks some. That referenced You Tuber above has done a knife in M398 at 66HRC.

I own that knife from triple b at 66 hrc. In my toughness testing it was middle of the pack. It's edge retention rivaled s90v and zdp189. It sharpens up very easily but that's a combo of geometry and Shawn's heat treat. I ordered a couple mules bcuz I grew tired of waiting for production offering from spyderco. I generally prefer posting my edge retention testing with accessible options not customs.

Awesome! Thx folks!

As someone who enjoys a fixed blade in the outdoors, I was thinking of M398 Mule.
Would this take well to bushcrafting / wood cutting tasks or is it more for around the home and office / warehouse ?

Mule arrived today. I tested the factory edge and I got 370. When testing the edge for overall sharpness during testing, it has a very aggressive bite. It has 30% carbide volume which is not a shocker. I could feel the carbides when I was testing the edge for sharpness.

SpiderIsland wrote: ↑

Fri Mar 10, 2023 2:50 pm

As someone who enjoys a fixed blade in the outdoors, I was thinking of M398 Mule.
Would this take well to bushcrafting / wood cutting tasks or is it more for around the home and office / warehouse ?

Doesn't bushcraft and woodwork generally do best with a steel that is reasonably tough? Larrin reports M398 “toughness ... lower than any other available stainless knife steel, including S125V” at around 3 ft lbs. If you do use for woodwork, no twisting cuts, eh?

Bolster wrote: ↑

Fri Mar 10, 2023 7:52 pm

SpiderIsland wrote: ↑

Fri Mar 10, 2023 2:50 pm

As someone who enjoys a fixed blade in the outdoors, I was thinking of M398 Mule.
Would this take well to bushcrafting / wood cutting tasks or is it more for around the home and office / warehouse ?

Doesn't bushcraft and woodwork generally do best with a steel that is reasonably tough? Larrin reports M398 “toughness ... lower than any other available stainless knife steel, including S125V” at around 3 ft lbs. If you do use for woodwork, no twisting cuts, eh?

Thanks for the insight. I will wait for a stronger steel.

At roughly the same hardness as the Mules. If this is not tough, I have no idea what is.

https://youtu.be/3FYdPN_WvKg
https://youtu.be/L4NRvqtYD8g&t=608s

TTFulltimer wrote: ↑

Sat Mar 11, 2023 12:06 pm

At roughly the same hardness as the Mules. If this is not tough, I have no idea what is.

https://youtu.be/3FYdPN_WvKg
https://youtu.be/L4NRvqtYD8g&t=608s

WOW! Some testing.
That gentleman does not hold back.
Now I will check the hardness on the Spyderco M398.

Tested a 400 super vit diamond edge and got 550 cuts. Factory edge got 370 and this edge got 550.

TTFulltimer wrote: ↑

Sat Mar 11, 2023 12:06 pm

At roughly the same hardness as the Mules. If this is not tough, I have no idea what is.

https://youtu.be/3FYdPN_WvKg
https://youtu.be/L4NRvqtYD8g&t=608s

I can assure you this is unlikely to be the same heat treat that you receive in the Mule's.... unless Luong of BCMW has somehow partnered with Spyderco to use this heat treat. Luong has been long developing his heat treat protocols and gotten some really impressive results but to my knowledge he has not given any of this over to knifemakers for their own uses. The last I spoke with him he was looking more at selling his work to industry in general, not so much cutlery. I can't remember what industry he spoke of, maybe cars, etc.

I am super excited. I think it will make an excellent hunting/skinning knife.

I saw a youtube video of an M398 chopper pulverizing a 2 by 4! It was 65 HRC! https://youtu.be/3FYdPN_WvKg

Anyone know the hardness of our M398 mule?

Steeltoez83 wrote: ↑

Sun Mar 12, 2023 8:39 am

Tested a 400 super vit diamond edge and got 550 cuts. Factory edge got 370 and this edge got 550.

Appreciate the tests that you do.

alphaneuron9 wrote: ↑

Sun Mar 12, 2023 8:35 pm

I am super excited. I think it will make an excellent hunting/skinning knife.

I saw a youtube video of an M398 chopper pulverizing a 2 by 4! It was 65 HRC! https://youtu.be/3FYdPN_WvKg

Anyone know the hardness of our M398 mule?

64ish

tcarltonw wrote: ↑

Mon Mar 13, 2023 3:40 am

Steeltoez83 wrote: ↑

Sun Mar 12, 2023 8:39 am

Tested a 400 super vit diamond edge and got 550 cuts. Factory edge got 370 and this edge got 550.

Appreciate the tests that you do.

Thankyou.

Today's testing with a 10-11 dps super vitrified triple b stone at 1k achieved 720 cuts in my testing today. Surprised not many gave this steel a fair shake when it dropped 4 months ago.

Steeltoez83 wrote: ↑

Mon Mar 13, 2023 11:55 am

Today's testing with a 10-11 dps super vitrified triple b stone at 1k achieved 720 cuts in my testing today. Surprised not many gave this steel a fair shake when it dropped 4 months ago.

Listening To "Experts" Yes I capitalized the LT on purpose.

I know, I know, this isn’t the purpose and it annoys the forum - but this is my best kitchen knife. I use it for everything. Blade is still sharp & no rust.

spook2517 wrote: ↑

Mon Mar 13, 2023 2:32 pm

I know, I know, this isn’t the purpose and it annoys the forum - but this is my best kitchen knife. I use it for everything. Blade is still sharp & no rust.

It’s your knife; use it in the kitchen if you want to, and don’t worry about naysayers! I use my Magnacut and B70P Mules in the kitchen too. They’re great for deboning chicken and turkey. The B70P was made when Mules weren’t thiccc behind the edge, so it’s great for dicing tasks as well.

attila wrote: ↑

Mon Mar 13, 2023 4:14 pm

spook2517 wrote: ↑

Mon Mar 13, 2023 2:32 pm

I know, I know, this isn’t the purpose and it annoys the forum - but this is my best kitchen knife. I use it for everything. Blade is still sharp & no rust.

It’s your knife; use it in the kitchen if you want to, and don’t worry about naysayers! I use my Magnacut and B70P Mules in the kitchen too. They’re great for deboning chicken and turkey. The B70P was made when Mules weren’t thiccc behind the edge, so it’s great for dicing tasks as well.

Are you suggesting the newer Mule's are thick behind the edge compared to older examples? Mine in M398 and Rex 76 seemed relatively thin for a production knife but I've never experienced any older Mule's to compare to. What sort of edge geometry do these come with 15-20 DPS?