Kershaw Mini-Mojo Steel? 440 or Sandvik?

nygiantsfan3342 · Sep 7, 2006

I heard a rumor that the Mini-Mojo blade was listed as 440A steel, but was really Sanvik 13C26. Can anyone confirm this? Thomas, Tim?

Thomas W · Sep 7, 2006

The Mini-Mojo is done up in 440A.

Artfully Martial · Sep 7, 2006

My mini mojo definitely behaves like 440A.

nygiantsfan3342 · Sep 7, 2006

Good enough for me, I don't remember where I heard that. Would have been a cool marketing error though...Like getting steak when you order hamburger!

JPD1998 · Sep 7, 2006

nygiantsfan3342 said:
Good enough for me, I don't remember where I heard that. Would have been a cool marketing error though...Like getting steak when you order hamburger!

Do you have one ? If you were thinking about getting one it's a great little knife... It has an interesting safety built into the flipper.

In some ways it reminds me of a mini spec bump.

Artfully Martial · Sep 7, 2006

I've got one. It's a great little knife. I think it's really beautiful too. I can't believe I'm saying this, but I wouldn't mind seeing a full sized one that looks the same, only blown up. The G10 insert looks really good and the recurve blade is gorgeous. My only stud lock. The AO did break on mine really quickly (last about a month), but it works fine as a manual now.

nygiantsfan3342 · Sep 7, 2006

Artfully Martial said:
The AO did break on mine really quickly (last about a month), but it works fine as a manual now.

You know better than that! Send it in! Kershaw will make it all better

AM, I would love a Mini Mojo the size of the Leek or Storm! I love the blade too!

And LRD, I do have a MM and I love the trigger safety. Much better than the blade guard safety.

nygiantsfan3342 · Sep 7, 2006

Artfully Martial said:
The AO did break on mine really quickly (last about a month), but it works fine as a manual now.

AM, you know better than that! Send it in to Kershaw and they will take great care of you! And I do love the blade on my MM, and I wish the Mojo came in a size like the Leek or Storm!

JDP, I like the safety too. I think its better than the blade tip safety on the leek.

iceaxe · Sep 7, 2006

nygiantsfan3342 said:
Like getting steak when you order hamburger!

More like getting ribeye when you order sirloin -- depends almost as much on the butcher and chef as the beef. 440A is very similar to AUS 6M/8 -- kinda like AUS 7. It'll take a wicked edge and though Sandvik may hold an edge longer, it's a lot easier to get that edge back on the 440A. I have a CRKT Walker Bladelock in AUS 6M that cost $35. Great edge out of the box and still has it.

BTW, I love my Mini Mojo. Very addiciting little bugger.

Larrin · Sep 7, 2006

iceaxe said:
More like getting ribeye when you order sirloin -- depends almost as much on the butcher and chef as the beef. 440A is very similar to AUS 6M/8 -- kinda like AUS 7. It'll take a wicked edge and though Sandvik may hold an edge longer, it's a lot easier to get that edge back on the 440A. I have a CRKT Walker Bladelock in AUS 6M that cost $35. Great edge out of the box and still has it.

BTW, I love my Mini Mojo. Very addiciting little bugger.

I think 440A is closer to 440A, or itself. 440A has way more chromium.

Artfully Martial · Sep 7, 2006

I find a pretty big difference between 440A and Sandvik. My friends (the storm owners) have experienced difficulty sharpening it though...

I don't like 440A in general. If the mini mojo hadn't been so attractive, I wouldn't have bought it.

As per sending it in...I pretty much never send anything in. It's something extra to worry about. Besides, I'm pretty happy with it as a manual.

My other two AOs have held up fine.

Larrin · Sep 7, 2006

Artfully Martial said:
My friends (the storm owners) have experienced difficulty sharpening it though...

It shouldn't be the steel that makes it hard to sharpen, I bet it's an edge geometry thing. Unless they've never sharpened anything harder than 52 Rc.

Thomas W · Sep 7, 2006

Dang Larrin, you and Cliff getting on us about edge geometry and our grinds is starting to make us a bit self conscious.

Larrin · Sep 8, 2006

Thomas W said:
Dang Larrin, you and Cliff getting on us about edge geometry and our grinds is starting to make us a bit self conscious.

Well, I didn't mean anything specific, I've only used one Kershaw knife, I was just making a general statement about difficulty in sharpening.

Cliff Stamp · Sep 8, 2006

iceaxe said:
440A is very similar to AUS 6M/8

AUS-6A is basically Sandvik 12C27 with a small amount of nickel and even smaller amount of vanadium, so you would expect the performances so be similar in many respects with AUS-6A having a finer grain and slight benefits to wear resistance from the small amount of vanadium. 440A is a very different steel, it has a lower maximum hardness and much higher volume fraction of primary carbides. It also has better corrosion resistance but much lower edge stability and ease of sharpening.
How they are hardened would be of critical importance as most really underharden the inexpensive alloys because they are used on inexpensive knives.

Larrin said:
It shouldn't be the steel that makes it hard to sharpen, I bet it's an edge geometry thing. Unless they've never sharpened anything harder than 52 Rc.

In general, steels tend to get easier to sharpen as the hardness is raised for several reasons, often simply because the properties for knife perforamnce are often increased. The edge is likely too thick given the geometry specified on other blades but there is also a big difference in trying to achieve very high sharpness with a fine carbide steel and a very coarse one.

Artfully Martial said:
My friends (the storm owners) have experienced difficulty sharpening it though

Take a x-coarse hone or even a file and hack the primary edge bevel down to 10-15 degrees per side. Apply a secondary edge bevel of 20 degrees per side. It will quickly stabilize and should then sharpen easily. If you are just doing light cutting you can go thinner still, however it depends on your skill/experience.

-Cliff

Larrin · Sep 8, 2006

Cliff Stamp said:
In general, steels tend to get easier to sharpen as the hardness is raised...

I agree, but if someone was used to sharpening soft steels, it might be initially difficult to sharpen a hard one.

Dog of War · Sep 8, 2006

I've never thought of 440A as having any mojo at all.

Cliff Stamp · Sep 8, 2006

The maximum you can achieve in that steel (on an average composition) is about 59/60 HRC. This takes a high austenization temperature, oil/cold and a multiple low temper/quench (150 C). Kershaw doesn't even achieve that with 13C26 and thus their 440A is likely one of the softest and easiest to grind cutlery stainless. It would therfore be rare to see complaints because it is too hard / difficult to grind. Generally grindability is usually only an issue when either the steel or geometry is really unsuitable for the work. The exception to this are people who sharpen with files as they need soft steels as otherwise the file simply can't sharpen the knife.

-Cliff

Thomas W · Sep 8, 2006

Oh yea, forgot to mention the heat treating as well as the ginds and edge geometry. Thanks for the reminder Cliff.

nygiantsfan3342 · Sep 8, 2006

Cliff Stamp said:
AUS-6A is basically Sandvik 12C27 with a small amount of nickel and even smaller amount of vanadium, so you would expect the performances so be similar in many respects with AUS-6A having a finer grain and slight benefits to wear resistance from the small amount of vanadium. 440A is a very different steel, it has a lower maximum hardness and much higher volume fraction of primary carbides. It also has better corrosion resistance but much lower edge stability and ease of sharpening.
How they are hardened would be of critical importance as most really underharden the inexpensive alloys because they are used on inexpensive knives.

In general, steels tend to get easier to sharpen as the hardness is raised for several reasons, often simply because the properties for knife perforamnce are often increased. The edge is likely too thick given the geometry specified on other blades but there is also a big difference in trying to achieve very high sharpness with a fine carbide steel and a very coarse one.

Take a x-coarse hone or even a file and hack the primary edge bevel down to 10-15 degrees per side. Apply a secondary edge bevel of 20 degrees per side. It will quickly stabilize and should then sharpen easily. If you are just doing light cutting you can go thinner still, however it depends on your skill/experience.

-Cliff

I am sorry I brought it Up. Let this thread die. My question was answered 6 posts ago. Sorry Thomas, I gave Cliff another chance to show everyone how smart he is...

Edit: Did I say 6 posts? I meant 17 posts ago!