My 100# diamond stones are now broken in. I sharpened a Cutco knife tonight, taking it down to 17 degree per side. It was probably 20+ to start with. Seemed like it took for ever to raise a bur for the initial re-profiling. I looked up Cutco steel and it looks like they use 440A which is low carbon and super high Chromium (16-18%). No doubt this is part of the problem.

I am wondering how everyone re-profiles, 100# or who has the 50/80s? What are your thoughts? I am thinking there is a trade off of speed in re-profiling vs. having some deep scratches to work out later (or can't get out)?

I am still working through my "junk" to average knives before I start my "super steel" knives. I want to perfect my technique and learn from my mistakes on my lower end knives. I assume that better steels will sharpen/re-profile faster. Maybe I just need more patience or do you like the ultra coarse stones? Or do they cut too deep?

If you use the ultra coarse do you use them on all re-profile jobs, or just on the harder steels?

I love my 50/80s. They cut the time down to reprofile the harder steels like crazy.
I have yet to try them on the "super" steels but I did try it on my kabar mule which was taking me forever to reprofile with the 100 and it literally went from possibly hours to minutes!!
I raised a burr in no time.
I think they are essential in the kit to be honest. As for taking out the deep scratches, I don't think it's that tough.
I've put mirror polishes on each one I've done even after the 50/80.
I would definitely give them a try if I were you.

go ahead and use the 50/80 grits. Take your time and give extra strokes as you increase your grits. If you have been working heel to tip, then change and run tip to heel. Just like in sanding wood and polishing plastics, and glass you have to break down the abrasion scratches into smaller and smaller bits.

Even some of the not so super steels take a good while to reprofile. A certain Becker#2 in 1095CrV comes to mind... Still it has a near mirror finish.

440 series stainless steels used to be concidered supersteels 30 yrs ago.

I now well broken 100/200 and quite new 50/80 now. I did many reprofiles with 100, so now are finer than my 200, so I use progression 200>100>400>600.... My 50/80 works much faster than 100/200. Stratches are quite deep, so I have to spend lot of time with my 200 ( I recommend to use small hand microscope from dealextreme to control taking out deep scratches), but in sum, it can spare a lot of time when heavy reprofiling. I think the scratches will become much shallower as my 50/80 will break in.

I have some knives made from similar steels to 440A, and reprofiling of them is quite fast in comparison with some other steels.

LukasPop,
How many knives did it take to wear down your 100 grit to be finer than your 200? Thought I read somewhere that the diamonds would be to sharpen around 500 knives.

TedS wrote:

Hi TedS, I did about 25 reprofiles. If you don't need to reprofile, the amount of work is much less. The edges after 100 grit look very well under microscope now, but the speed of reprofiling is reduced. I don't know how long this state will persist. But it seems to me that diamonds are rounded only, not removed from the base, so I think they have much time ahead. I suppose finer grits to endure very long as you don't use (you shouldn't) pressure when refining the edge.

LukasPop wrote:

I was wondering which microscope you were talking about on the website. I was looking and they have a bunch.

Geocyclist wrote:


Thoughts on the 50/80s; have re-profiled the edge on 12 Chicago Cutlery kitchen knives. My 50/80 are not even close to breaking in. Several of the 12 did get some deep scratches that may never come out. That is Ok since I am just after a good cutting edge on them. Keeping a light touch works better and they are quick to set up a nice starting profile. When you first start the 50/80 they are hard to describe how rough they are. I would want them to break in a lot more before I would consider using them on a more expensive knife.

MartinL1 wrote:

This one dx.com/p/60x-100x-zoom-microscope-with-l...mination-light-25239

I haven't used the 50 and 80 grit diamond plates, so I couldn't comment on them directly.

I do make the Atoma diamond plates for the Wicked Edge in 140 400 600 and 1200 grit.

The Cutco steel isn't a particularly hard steel - just the opposite. And you aren't drastically changing the angle or reprofiling the knife to an extreme angle (which I wouldn't recommend doing on a Cutco in any case).

The 140 Atoma will make short work reprofiling a Cutco - or any of the much more highly abrasion resistant steels as well.

It is one of the most popular products I make (also for the EdgePro) specifically for this purpose of creating an initial reprofiled angle. I usually recommend following this with a finer diamond plate for more abrasion resistant steels or going to a stone like a 150 Nubatama waterstone or 220 grit Shapton Pro stone. The stones 'convert' from a diamond scratch pattern to a 'softer' waterstone pattern.

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Ken