CPM M4 - Finishing for hair whittling edge?

[Gunsnknives]

Good day all,

I recently acquired the BM Contego and love just about every aspect of the design. I love the reverse tanto, ergos and how the blade thins way down toward the cutting edge. However...

I am having difficulty consistently getting the edge hair whittling sharp. I can get my M390 Smurf Blue PM2 and ZDP189 Endura 4 hair whittling sharp...but I'm just having issues getting CPM M4 that sharp.

I use my EP stock stones >> finish with tapes >> Chromium oxides strop >> Bare leather strop.

Perhaps I'm simply comparing a good steel (M4) against excellent steels (M390 and ZDP189)? Perhaps I need more time on a bare strop?

Any insight would be appreciated.

 

[unit]

M4 is very able to whittle hair, it seems that M4 responds very well to stropping with diamond paste.

If you are able to accomplish this with ZDP-189, M4 should be no problem at all. Just keep trying.

Proof of concept
(Finished on a strop with 1 micron diamond paste)

[video=youtube_share;h21dxRiZTbc]http://youtu.be/h21dxRiZTbc[/video]

 

[Jason B.]

Diamond products really help but I will give one tip, thin the back-bevel and micro with a spyderco UF ceramic before using1 micron diamond compound to strop. It will bring the most out of M4.

 

[Gunsnknives]

Thanks for the tips. I cleaned my strop which seemed to help a bit. Also, the geometry of the Contego seems to make it just a little harder to consistently sharpen (because of the way the reverse tanto swoops down from the tip, to the belly, then the straight of the blade to the heel). Perhaps I just need to practice on this geometry and try some of your tips above...Sharpness is already improved by just cleaning the strop.

I'm glad that there seems to be no limitation to this steel...I really like the way it performed in my test today and the easy with which I was able to restore the edge. So much cardboard and only a loaded and bare strop to bring it back to almost hair whittle sharp .

Thanks as always!

 

[unit]

There are limitations for every steel I had played with, but M4 is certainly good stuff.

One reason I really like it is (as you have indicated) it retains a really keen edge and very little seems Ti be required to bring it back when it does degrade a little.

I also like it because it will take a serious beating seemingly with a smile.

 

[capid1]

I usually use the EP using the stones but I added a stropping routine using a 3micron and then 1 micron CBN paste on balsa. I just resharpened my M4 Manix with this method and it came out great!