Edge Journal: M4

[A.S.O.K.A]

Before I start, let me be clear that results will vary from person to person depending on heat treat, use, materials being cut, how the knife is sharpened and maintained. I have sharpened the para3 Cpm M4 on my edge pro with the following: spyderco diamond rod, dmt aligner plate( 600 grit) and edge pro stock 1000 grit stone. Then I stropped it on leather with diamond compound in the following microns: 5, 3.5, 2.5, 1.5, 1, 0.5 and 0.25. After that sharpening, I have been using the knife since the middle of March to present. the knife has been stropped at the same microns once a week to keep it hair whittling sharp. it has been cutting the following materials on a weekly basis: cardboard( it varies from light, medium or dense), cloth, tape, very few times plastic and paper. Some of the materials are in the picture. [attachment=0]20190429_084336.jpg[/attachment

As of now, the knife is no longer hair whittling sharp, but is currently news paper slicing sharp. I will update this post until the knife needs to be sharpened. If anybody has questions, comments, or would like to share their experience with M4 steel, feel free to post.

[Albatross]

Interesting. Aside from a decline in initial sharpness, how much of a decline have you seen in overall edge retention?

[A.S.O.K.A]

Interesting. Aside from a decline in initial sharpness, how much of a decline have you seen in overall edge retention?

The hair whittling edge is marginally reduced by the 4th day of use in the week. There is less use during the weekend. Usually by Sunday night, the blade will be stropped. The final results of the over all decline in edge retention won't be concluded until the blade needs to be resharpened. The CPM M4 para3 has been used for 48 days as of today.

[A.S.O.K.A]

Here is a photo of me using the knife to cut plastic straps on Friday, May 3.

The knife afterward was tested slicing news paper. It showed little wear with a snag or two on the pinnacle of the apex. May 5, it is now morning and the knife hasn't been used yet. I will be stropping it tonight, and will keep up to date with my findings.

[A.S.O.K.A]

May 10 makes it 56 days of use for the M4 para3 doing nothing more then stropping at the end of each week to recover some levels of sharpness. last Sunday I stropped it with 5 and 3.5 micron diamond paste on leather as apposed to the lengthier progression of stropping. I did this because the edge retention is showing more significant loss. On May 8, I tested the edge mid day on slicing news paper and found the edge was starting to snag in a few spots. Checked for edge roll and there were very few spots of it. I have not used the knife yesterday and later on tonight it will be stropped using only the 5 micron on leather. This coming week may be the last week for the edge. Only time and use will tell.

[Ruudr]

Thanks for the update! I will test my M4 Native 5 next week.

[A.S.O.K.A]

Thanks for the update! I will test my M4 Native 5 next week.

Sounds good. Let me know how it turns out.

[A.S.O.K.A]

I had not used the M4 para3 over the weekend, so Monday and Tuesday became day 57 and 58. I Stropped the blade only using the 5 micron diamond paste on leather Sunday night. the blade is now strictly slicing as it no longer push cuts, minus a ziptie pictured here

Still slices news paper after cutting a ziptie and cardboard corners for strapping material

[A.S.O.K.A]

My final conclusion to my edge journal of CPM M4 can be found in this vid link below

https://youtu.be/BBNTsGFRPhM