Rope cutting test on 3 convexed blades/diff. steels

Joined
Jul 9, 1999
Messages
3,316
I had some time to kill today so I thought that I would do a little comparison.
I was wondering how three different steels with convex edges would stack up cutting some 3/4" manila rope. This exercise is done just out of curiosity and although I'm sure at least one of you has undertaken this task before, I can't seem to find it here on the forum. Sooo I thought maybe this should be shared to satisfy any curiosity that might be out there.
The subjects for this exercise are:
1. Blackjack Trail Guide A-2 steel Rc 58-60(?) I'm unsure about the hardness. Anybody know? Please advise.
2. Marble's Plainsman 52100 steel Rc58-60.
3. Spyderco's Moran Featherweight VG10 steel Rc60-62.
The rope was placed in a brace not unlike the one that appears in Cold Steel's PROOF video.
The rope was cut in the same manner as is seen in PROOF. With a straight down cleaving type cut (the type of cutting they used when testing the Trailmaster). The cutting for each blade concluded when the edge would barely scrape hair from my forearm with relatively heavy pressure. I saw no use in taking it any further. The aggressive cutting action was gone. Each knife had a factory edge and each knife was hair popping sharp at the start. The Marble's and the Featherweight are recent acquisitions and the TrailGuide was purchased and put into the collection several years ago and was never used.
The TrailGuide made 121 cuts.
The Marble's made 124 cuts.
and, The Featherweight made 88 cuts.
Now, the results IMO are outstanding. I must emphasize that if you try this yourself: YOUR MILEAGE MAY VARY. No two knives of the same make and model are exactly alike. Too many variables involved. The knives' position in the heat treat oven, who was manning the sharpening station at the time, the grinding process, so on and so forth.
That being said, does anyone have ideas as to why the Spydie which has the highest Rc made the fewest cuts. Please do not think that I am down on this steel(VG10)as it is one of my very favorite stainless steels. And rightly so. It is that good.
Any input would be most welcome! Thanks!
 
This confirms what I have seen in production knives. High-carbon "standard" (non-particle-formed) stainless is super, but simply not in the same class as non-stainless "carbon" steel. Blackjacks remain the sharpest and most easily re-sharpened factory knives I've ever seen (the A-2 Trailguide is the king of their line in this) and I've been eyeing the Marbles knives as possible successors to Blackjack. Cold Steel's Carbon V is nearly as good, too. I find that I just cannot judge these knives by the same standards I apply to ATS-34, 440C, AUS-8, and other good stainless types. Haven't formed an opinion on the particle steels yet. I'm curious to hear what others say, but while I personally want (and make) a "stainless" knife in most cases, I've found that a blade of A-2, 52100, or even 1095 will outperform it in almost every case.

------------------
-Drew Gleason
Little Bear Knives
 
No shock here. I correctly guessed what the outcome would be before getting to the results. What can I say I am a BlackJack fan and the Trailguide is my fav. The Rc on that is 57-59 btw. One question I have and I suspect I know the answer is this. Does the marbles have a thinner edge than the BlackJack? I am guessing it does. Next does it have a thinner edge than the Moran? One thing to keep in mind is a thinner edge has less resistance to overcome and will cut easier than a knife with a thicker edge.

Regards,

Tom Carey
 
Misque, RC hardness is not directly linked to edge holding as in higher RC = better edge holding especially when you compare different steels. Edge holding is primarly a factor of wear resistance and impact toughness and these are determined by the steel properties. For example 3V at 58 RC has twice the wear resistance of A2 at 60 RC and significantly more impact toughness (stats from CPM).

The problem with some of the high %Cr steels is that they can have large carbides which give good initial cutting performance but they break off easily and leave a very ragged edge which does little but tear (it won't saw). There are exceptions to this, some of the CPM stainless steels are supposed to be very good as in regards to edge holding. The only one I have seen speak against them is Kevin McClung.

-Cliff
 
Gentlemen, Thank You very much for your replies. Some additional info:
The Marble's does have a thinner edge than the TrailGuide and the Spydie has the thickest edge of the three.
All three came back to hair popping sharpness after a short (30 seconds or so) stint on my buffer @ 3100 RPM and lightly charged with white L'Hommedieu compound. Not to worry about burning the temper off, I'm an old hand at this.
I sincerely believe that Marble's is filling the void left by BlackJack and doing a first rate job at it too. I was in a real funk for several months after BJ went belly up. Their products were all Top Shelf and I for one sorely miss them but Marble's is now easing that pain.
Lastly, I find that the Carbon steels really do perform better than most stainless. I first started noticing this when I began making file knives. Drawing the spine down to the low 50's and keeping the edge in the high 50's the file knives were holding a more aggressive edge than my 440c blades(also in the 58-59 range). NOT that you can't get a frighteningly sharp edge on a 440c blade, it just doesn't seem to stay that way for very long. All in all though, I thought that the VG10 did a rather admirable job for a stainless. I would really like to see this test done with some of the new Particle steels and non-steels like Talonite.
Thanks Again!
 
My guess seems to be correct on the edge thickness of the knives tested. I agree that Marbles seems to have taken up where BJ left off. No shock since Mike Stewart is head of production and most likely has a lot of say on how the knives are made.

Regards,

Tom Carey
 
I've got a Marbles Campcraft 2000 which I really like. I used it on exactly one hunting trip and field dressed exactly one deer with it. When attempting to crack a pelvis (something I have done many times with other knives,; dome by tappping the pelvic girdle with a knife while the legs are severly separated puting tension on the pelvis).

The pelvis did not break and I had chipps in the blade.

I contacted Marbles and they, of course, offered to make it right at no cost other than shipping. I took a few minutes on the Sharpmaker and the blade came back, sans chips. Maybe what I was experiencing was those carbides breaking off that Cliff Stamp referenced in his post, "The problem with some of the high %Cr steels is that they can have large carbides which give good initial cutting performance but they break off easily and leave a very ragged edge which does little but tear (it won't saw)."

The thin blade geometry of the Mrbles probably had something to do with it as well. Any similar experiences?
 
Blackjack Classic Blades are/were notorious chippers on bone.

They have such an acute edge angle that their slicing ability is severely hampered by their ability to chip on tough materials.

Blackjack A2 knives are great knives. I have dozens of them....they just seem to work better after re-sharpening to a thicker edge..

Same with marbles-my 52-100 sport 99 is a great little knife-gets razor sharp and sharpens easily...a few bone hits and it was all chipped though--oh well...too thin!

FYI. Mike Stewart who ran Blackjack, also is in charge of Marbles knives...he knows edge geometry and all his knives cut real well, although at the cost of being too thin.

Having the sharpest knife in the dealers case was a big part of the Blackjack marketing scheme, and it seemed to work for a while.

 
Did you find that resharpening at with the Sharpmaker ceramic sticks in the 30 degree position thickened sufficiently? Or did you use some other tool/method?
 
Originally posted by Cliff Stamp:
The problem with some of the high %Cr steels is that they can have large carbides which give good initial cutting performance but they break off easily and leave a very ragged edge which does little but tear (it won't saw). There are exceptions to this, some of the CPM stainless steels are supposed to be very good as in regards to edge holding.

This is the first time that I've read this, but it makes the most sense so far of anything I've read about stainless steels. It probably explains very well why I see what I do of ATS-34. It will shave, and continue to, but after cutting a couple of things just a bit, it tears through fibrous materials (paper, cloth) more than other steels. Or maybe tears isn't quite right; it appears to cut, but it drags portions of the fibers with it, and after the cut, they are stuck to the edge of the blade. It is really ODD. Another odd thing is, while I see this in every ATS-34 blade I have, I haven't seen it in the 154CM blades that I have. Even from the same manufacturer. Interesting, if that is what is going on.

Nimrod, one problem with your hypothesis is this: if your Marbles is 52100 steel, which I think it is, it is not a "hight %Cr" steel. In fact, 52100 is a very low chromium steel.
------------------
iktomi

[This message has been edited by rockspyder (edited 12-05-2000).]
 
Some of the best/keenest knives I've ever used have been turn of the centry kitchen or utility knives. Non were stainless and most were coloured black from staining. Must be the high carbon content.

Anyone know the make up of these early steels?
 
Back
Top