CPM 440V... Weird results!

The General

The General

Joined
Jun 6, 2000
Messages
3,625
My Spyderco Mil has just been tested. Here is what I have found.

1. I cannot get the edge 'smooth' sharp. When using the Sharpmaker 203 with the white stones, all I gat is a very sharp edge, but it feels very 'rough' when I shave arm hairs.
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2. My M2 steel blades using the same sharpening style are razor razor sharp. Any ideas why this is so? I am not dissapointed just surprised. Is this normal for this steel? First knife in it!

3. The knife does not seem then to take a polished edge as well as m2 steel, it seems more like the m2 sharpened with a 600 grit or even a 400 grit stone.

4. Sal, is this an inherent trait of this steel? BTW, it is one kick ass knife! Love it
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"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
General. The properties of the CPM material seem to be different in many respects than normal ingot steels. We're still learning ourselves. I think to get a very very razor sharp edge, buffing might be necessary. Using the narrow angle is possible, but I don't think the blde would be as tough as the wider angle.

I've also found that continual light stroking on the white stones of the Sharpmaker will actually make a difference even after very sharp.

sal
 
Thanks Sal!

I would love it if you could post or e-mail me with the findings with this steel. To reiterate, is this sharpening finding of mine normal? The white stones may have some steel on them from sharpening. Though it has not been a factor with other knives and I cleaned them with a nylon pad and fairy liquid a few weeks ago. I have only used them once or twice since for slight honeing.

I would be very interested to find out if anyone else has seen this 'effect' in this steel. I have many knives and this is my first 440V blade.

Thanks all

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"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
General,
I have no problems to sharpen my Military on Sharpmaker 204 to very decent shaving sharpness. It shaves the hair on my forearm practically under blade's weight only, with no additional pressure applied by hand.
I have sharpened mine with 40 degrees main bevel with quite wide 30 degrees back bevel.
Try to finish your edge with very light strokes, the last dozen of them one stroke on right rod, one - on left etc.
Sal,
You are right, the very thin edge on CPM440V is not as tough as on ATS-34 or especially M-2. I have experienced this with both Military and Starmate. But the normal 40-degree edge holds up very well, especially when slicing.
 
Thanks, unfortunatly my model is the 203, it does not have the 15% option. I am sure at that angle I would see a VERY sharp edge.

Perhaps I need to give the knife a little more time to 'bed' in? Still it is simply different? I dont know as yet. I bet your knife has seen a little more action than mine!

BTW, I read your 6 knife test with interest. Good article!

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"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
D OH double DOH

Just noticed
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My Mil has lost a screw
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maybe I did not tighten them enough
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. Any chance someone knows where I can get some?
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Thanks all!

P.S. Sal I would love to hear the history of this knife.
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What it took to get it made! Sal Your the man! Thanks for this knife well worth the cash!

W.A.

------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
General,

See my post in the "Sharpmaker Questions" thread; I'm not having much luck sharpening my Military either.

Steve
 
General,
My Military is sharpened with 40-degree at the very edge. You can obtain the same edge with your model 203. The 30-degree back bevel improves cutting performance only but it is nothing to do with edge sharpness.
 
Thanks Steve! Yes, very interesting. To be more precise I have got a hair cutting edge, slicing with moderate pressure. I am unsure why it wont cut like my M2 blades? Perhaps because the edge that cuts like a razor is a 'wire edge'? Maybe 440V is more resistant to this? However you do seem to be having problems of a different kind. All in all I am confused about this.

This knife is still, very sharp however!

I did notice that it will pop hairs if I let the edge become more biased to one side than the other, i.e. I let a very very tiny wire edge form on one side, the edge is then not equal on both sides. Many would not call this a wire edge as you can only tell it is there as the edge shaves better on one side than the other, it aught not to do this! I have not left it like this, just noticed this while testing and sharpening. Maybe 440V will take more time and use before it beds in? I think Sal was suggesting this.

BTW, how did you chip your knife? Is it one of the older models with a higher Rc scale? Was it plain or serrated? Thanks!

Oh, sorry, yes I realise now that 30% refers to the back bevel, I was not paying attention, sorry!

W.A.

------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
Ok, new results!

Cleaned my 203 with a pad. Started again!

Used a 10x mag glass on edge.
Faint wire edge on right side edge.
Used white stones and began sharpening.
One hour later I realise that rather than removing the wire edge, I am turning it back and forth. Yegads this 440v is wear resistant! So I stroped it on the stone and once the wire was gone started again. I did this 10 one side 10 other 9 8 7 6 5 4 3 2 1. Finaly I had a very nice edge with a tiny wire edge. I used my thumb as a guide and got the edge symetrically sharpened. Whew! Under the scope no wire edge, thumb test.. Fine! Hair shaving! God yes! Happy? As a knifeman can get!

So to recap, use very very very very! Light strokes at the end half i.e. 5 then 5 4 then 4...

Use the grey stone to remove the wire, not the white as I did. It takes a LONG time! CPM 440V is a bugger to sharpen, it just fights back! It does not want the stone to cut it!
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Looks good for cutting performance!

The blade came sharp, but not sharpened properly. I have now fixed this.

Hope it helps someone!

W.A.

------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
Hi General. congratulations. Thanx for the effort and persistence. Yes, it is different in some respects than ingot steels.

And while "we" continue to test and experiment, "we" will learn about this new aquaintance in "high tech steels".

In order to progress, somebody's gotta do it, somebody's gotta try it and in that way we push the tekno rock through time.

Regarding the history of the Military; the model has been an adventure. We went through many wood and plastic models developing the pattern. There were no parameters other than "Very high performance". Light, strong, reliable. I believe this to be an "optimum" folding knife size.

We'll be refining the materials and particulars over the years, but the basic pattern will remain.

sal
 
No no nooo Sal, thank you! From what others have told me, you are the man behind the Military
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. CPM 440V is different, but was it not Spyderco that started the factory trend?
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I think so! This steel will cut and cut and...
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And it resists rust very very well
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. Hell my one real worry now? Edge chipping
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. Most say I have little to worry about
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. So here is a question, if I was to chop away at a 2x4 would the edge chip out or roll away on me? I have been told that 440v at 55-57 aught to be fairly tough. Sorry to keep on about this, but as I see it it can be 440v`s only real weakness.

W.A.

------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
Last year, someone chopped a 2x4 in half with a Military. (I think it might have been Ewok, but I'm not sure) He posted about the experience; no damage to the edge or overall knife reported.

I noticed the same thing sharpening the Military: a small burr forms that tends to flip back and forth over the edge. Using extremely light strokes on a very fine stone will at least center the wire, but I'm still not sure that it's actually grinding the burr away. The edge this creates is vorpally sharp.

Maybe the Military's 440V would be a good canidate for light stropping, as it seems like that could remove the wire without pushing it. I haven't really tried a normal stropping with leather, but I did try stropping with cardboard. It didn't work very well; 440V is so wear resistant that the burr just tore up the cardboard.
 
BTW general - the steel is CPM440V, somewhat different then 440V - just crossing the T’s and dotting the I’s for you...

[This message has been edited by Blilious (edited 10-30-2000).]
 
Ok I will!

------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
Ok, more results!

Bought two 2x4 planks in B&Q today. They were both dry as a bone and made from the standard cheap softwood.

I began by hiting the Mil into the first 2x4 using wrist action only. I did not want to damage the blade! After about 30 mins of this I had cut through about 3/4 of the 2x4. I was being very gentle with this. I turned over and finished the job. The knife was still sharp, but no longer shaved. No sign of any damage at all!
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Second 2x4, this time I used rather more force with the chopping action. Not as much as with a fixed blade but about six times the force as before. I brought my hand about 2 foot above the 2x4 and hit it downward with enough force to drive the edge about 2.5cm into the wood. I cut the begger in half in about 10 mins. I was sure to make a V shape cut so as to lessen the marking on the knife.

The edge was still usable as a knife, however the mid point where I chopped showed a 1.7 cm patch of 'white' under the lamp test. I looked closer with a 10x mag glass and the edge had chipped out
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in two small places and rolled. It took me about 20 mins to sharpen this out. The chip marks were very very minor.

I am somewhat surprised it chipped, but then it is NOT a fixed blade is it?

1. The blade was covered in gaffer tape to protect the finish. This would have effected cutting times as it caused more resistance.

2. The edge was sharpened using the Sharpmaker 203 using the white stones at all times. The total angle was 40% and no back bevel

W.A.



------------------
"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
I don't understand it either, but some steels "bite" more than others. ATS-34 and D-2 (as well as anything softer, like AUS-6, etc) tend to get shaving sharp very easily. On the other hand, I have a Hossom knife in 3V and just got a Spydie Viele in VG-10. These blades don't SEEM to get very sharp. The cut paper all right, adn pop a few hairs, but they obviously don't shave at all. But increase the cutting angle just a tad, and you'll bleed like the proverbial stuck pig. These steels seem to cut the user better than most anything else
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I don't know whether it's the grain of the steel or what, but they sure do "get ya". i was playing with my new Viele and thought "It's not nearly as sharp out of the box as my other Spydies." Before I knew it, I looked like I had been worked over by renegade farm machinery. Nicks and cuts everywhere. Didn't even notice at first. Go figure...

Tom
Big Dawg #581
 
Heheheheheheheehe
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Noticed that as well!
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I think it comes down to a wire edge, softer steels are easier to sharpen as a result. The better steels are only worth it if you can really sharpen a knife. By this I mean judge perfect edge symetry
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with a thumb! It takes a lot of practice! It is worth it for us 'experts'
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Not a knife nut? Get a basic knife from CRKT in 6a or 8a. Once you are happy with sharpening, move up. Thats what I did (it was a 440a Gerber ez-out). The new steels take a lot of patience and work to get used to them.

W.A.

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"To strive to seek to find and not to yield"
Tenneson
Ranger motto
 
I think I am getting to this post somewhat late, but I would like to give my 2 cents worth. I have Military in CPM 440V and a Calypso Jr. Ltw in VG-10 that I wear to work and around the houe. (Drives my wife fn nuts!) I have been able to get the Calypso scalpel sharp with the 204 and the white stones. I don't dare shave my arm anymore--I usually draw blood. The Military is anyother story though. It's polished edge from the factory stayed sharp a very long time. This last summer when I bought it I discovered from reading posts here that it came from the factory with a 30 degree edge. Sal Glesser even stated in a reply that he was maintaining his Military with a 30 degree bevel, in his words, "to push the edge". I took that to mean that he thought the Military could perform with that bevel. Sal, if you are out there, what were your conclusions? 30 or 40???
Anyway, I have had a heck of time keeping my Military factory sharp. This weekend I broke out my Japanese waterstones and a jig that I built to hold the stones at a 15 degree angle, ala' the 204. and began working the Military with an 800 stone, a 1200 stone and a gold (9000) stone. Well, to keep this story moving, I didn't get the results I had hoped for. The Military is very sharp, but after reading th eprevious posts, I am assuming that I am having difficulty totally removing the wire edge. So my next question is how do you polish an edge to remove the burr? 3M makes lots of new polishing abrasive sandpapers. Any one have luck with these? How about a leather buffing wheel with jewelers rouge? Any thoughts on steels?
Thanks for reading this. I woud appreciate anything describing how to polish an edge.
Barry H.
 
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