ODC - Cut your sharpening time in half (or do 2x better, your call)

I told you that things would get interesting, didn't I? Didn't I?

Well, for those still awake, this stuff is REALLY neat! I saw such dramatic results by using the ODC nagura that I needed to do some more comparisons.

The ODC made the stones FAST, so lets see how fast....starting here with a different chisel and DMT Xfine 1200 diamond finish. Lets try the Amakusa, my everyday stone...

30 second intervals. No ODC, not much happening. Starting to see some definition, though.

Add ODC slurry

+30 s. Scratches disappearing, lots of dark slurry forming. Lamination line fully visible.

+30 s. Better

+30 s. Better, but diamond scratches are still visible.

+30 s. No significant change, diamond scratches still visible...

As are the sharpening scratch pattern from this stone. This is pretty good. WAY better than using the Amakusa with just a diamond nagura! You know what I am wondering? Lets try the hard gray shale from GSS.....

Back to square one

+30 s. Yeah, I like this one better...the diamond scratches are almost gone, there are a few faint ones from the gray shale. Lets try the volcanic tuff....

+1 minute. Lets try the Altamura shale...

The shale fractured along some seams that weren't visible. I didn't care, because it didn't seem to work very well. With this chisel, though....totally different! Lots of black creamy slurry and strong polishing power.

+1 minute. This is about as high as this stone will go, maybe JIS 6000-80000. The stone is small and has a chip right in the middle of the surface. Rudy is looking for a better one for me.

So when I sharpened the other chisel on the same stones, I got a higher polish. I assumed that it was because THIS chisel is new and not as hard as the old mortising chisel. This stone is hard, so naturally I thought that IT was scratching the steel, so this would be the highest finish possible. At least for this combination. Remember when I said that each combination of stones yields different results for different tools?

honegrown- Geological Specimen Supply (GSS) - Altamira shale

Paraphrased from GSS....

Altamira shale, lower member, Palos Verdes Hills, Los Angeles Co. CA

Middle Miocene shale, oldest of 3 sub-units of the Monterey Shale, contains volcanic ash (and possibly formed with silica in solution). Very pretty stone, it shows a slightly crystalline composition and looks somewhat similar to some (too)hard Montana shale that I have tried.

Starting from where we left off with the welded volcanic tuff, this picture shows the results of 1 minutes work....nothing. No black particulate, no slurry, edge may be burnishing slightly, but not enough to note. Very hard, moderately sticky, feedback not too good.

This is after a rinse and using a DMT Xfine P2400 diamond plate to raise a very thin slurry, then working the edge for 1 minute. A little black, no additional slurry generation, very slight polishing. This is looking like another garden stone, I guess. Not too much action, feedback was improved by the diamond slurry. Only slightly sticky now.

Rinse, ODC nagura, 1 more minute. Creamy slurry formed and darkened immediately, edge is polished, steel is bright mirror, iron is dark mirror, even haze.

Iron is reflective too, maybe around JIS 8000?

Check out the trees!

ODC made the difference. So now I am thinking that the ODC is responsible for ALL of the different behaviors shown by the various stones. It turned this one from a sticky, pretty, dud to a respectable performer. Not stellar, but fair/good. Feedback was very nice AFTER the ODC nagura. I am thinking that this stone is too hard and new particles aren't being released fast enough to really work the metal in a timely fashion.....come to think of it, it feels like an oilstone! Like a hard Arkansas/Novaculite.

I'm still trying to figure out this stone. I will revisit this one soon.

RIVETING, ISN'T IT?