Great stuff Clay! Every time you work on a knife for us to see, I learn something else to add to my knowledge of sharpening. When I first started with the WEPS, the whole thing was more or less mechanical in nature, but watching you and others here too, the act of sharpening can also be an intellectual experience. Since that happens to be the way my mind works, I am improving my edges more and more as I watch and read your work and that of others here. It is an education.
Tell me how the Farid knife opens and closes...is it smooth and is the lock-up strong. Obviously the knife is built like a tank with that super steel and titanium body, but is it more than just a super strong knife in your opinion?

Leo

You're right Leo that it's built like a tank but the action is smooth and the lock is very strong. It's a no-frills work horse in terms of design but it has great visual appeal from the hammered Rex 121 and the matte gray titanium.

I just completed the initial bevel formation which took about 5 minutes per side to erase all the marker and grind marks. This is the second Rex 121 knife I've handled and each time I've been very surprised at how easily the diamond plates cut through the steel.

That is surprising for such a steel, but it bodes well for developing a sharp edge and keeping it maintained. Many of the people who were buying were speculating that it would be difficult and time consuming to sharpen this kind of blade of REX121 Crucible steel.
What angle or edge geometry do you think would be best for this blade Clay?

Leo

Here are a few pictures of the blade as it's come along:


After the 1600# Ceramics




Stropped down to 0.5um on cow leather

I'll get some better photos snapped with my big camera later, for now I snapped some quickly with my phone.

leomitch wrote:


I'd heard from someone else that REX121 and diamonds work well together - seems to be the case. I'm not sure about the optimal angle, it's something that you'll have to test a little. I suspect that the 0.5um finish is probably too fine and that you'll probably want a slightly coarser micro-bevel, but won't really know until you start using it. I left at 20 degrees per side for now which seems reasonable. If you find that it holds up well, it might be fun to take it a little lower though I think this knife is designed for hard work, so maybe just leave it a little more obtuse...

Clay, Do you think the hardness. 68 / 70 RC. Is a factor in why the diamonds work so well?
The new edge look incredible!

JamesBell wrote:


That's a tough question - I've worked with a lot of other super hard steels like the friction forged D2 from Diamond Blade Knives which also get into the 60s for hardness, some of the Hitachi steels, ZDP-189... they all feel and respond differently with the diamond plates, probably to do with wear resistance. I guess that the REX121 is hard and fairly tough but not extremely abrasion resistant.

A couple more photos:

People who are interested in this knife might like to jump over to the Blade Forum and search 'The Farid K2 Rex 121 Folder' to see a review by an owner. To show the reliability of this edge for holding its sharpness, he hacked through 5/8 inch manila rope 412 times until his hand and wrist were numb and the blade still neatly sliced through a thin page of telephone book paper. The review is interesting. He made a 15 degree per side convex edge and is very happy with that. A good read.

Leo