New study, different steel. This is a knife that I had made from CPM-154, hardened to 69-70 RHC.

I started with a polished edge, then went back to the 1000 grit stones before progressing to the strops. Here is the edge after the 14µ strops:


510x - 14µ diamond and leather strops after 1000 grit diamond stones - 100 passes


510x - 10µ diamond and leather strops after 14µ diamond and leather strops - 100 passes


510x - 5µ diamond and leather strops after 10µ diamond and leather strops - 100 passes


510x - 3.5µ diamond and leather strops after 5µ diamond and leather strops - 100 passes

Next I decided to throw in a little side experiment - I sprayed some Hand American, 1 micron diamond spray on my already pasted 1 micron strops - big difference here, though not totally surprising:


510x - 1µ diamond and leather strops after 3.5µ diamond and leather strops - 100 passes

There are clearly a LOT more diamonds than when I was using the strops with just the paste. Additionally, most of the 'stiction' was gone from the strops after spraying with the HA spray. I decided to do another 100 passes and started getting back to good 'stiction':


510x - 1µ diamond and leather strops after 3.5µ diamond and leather strops - 200 passes

For reference, here is a pic of the 1 micron pasted strops from a little earlier before adding the 1 micron spray:

razoredgeknives wrote:


If you can hold out til mid-May, I might have just the thing for you!

wickededge wrote:


+3.

However, this is the Wicked Edge pastes. Tonight I took photographs of the edge after stropping with Dovo paste. But it is 0:40 in the night here and somebody in the next room is saying I must come to bed. Up tomorrow .

mark76 wrote:


Can't wait to see your results!

Interesting experiments again, Clay!

wickededge wrote:


Why do you think they are not overwhelmingly better? I clearly see scratches now that (I hope) are from the polishing tapes. They are also quite evenly spaced, creating a nice pattern almost like what a stone would do.

By the way, with current knowledge (it changes per day ) I think this it the way to test the very low micron size compounds/tapes/stones: first burnish the edge until it is very smooth (e.g. using the 1 micron paste, but I wouldn’t be surprised if the 14 micron paste worked as well ) and then do strokes with the fine stuff.

razoredgeknives wrote:


I think we should be careful in drawing such conclusions too early. In one post Clay noted that the 1 micron compound had by far the most stiction. That would imply that 300 strokes with the 1 micron paste should produce more burnishing than 300 strokes (in total) with the 10-3.5-1 micron pastes. But in fact the surface of the edge after the latter progression looks smoother.

I had similar results: sometimes a particular compound seemed to cause more burnishing than another compound, whereas in different circumstances the results were exactly the opposite. I think this might very well be the result of the way in which the strops were seasoned (and the amount of paste applied).

wickededge wrote:


Are you sure that hardness isn’t a typo, Clay? But good to see the burnishing works just as good on harder steels!

wickededge wrote:


I am not quite sure what I see here. I I do see scratches, but not as many or as regular as those that would be caused by a 1 micron stone. Is that correct, Clay? If you’d increase the amount of spray applied, would the number of scratches increase and a more regular pattern appear?

Ooops, I did mean 59-60 RHC! I'll stitch the 1 micron paste image to the 1 micron paste + spray so we can compare them side by side.

Yeah Mark, you may be right... I guess I'm a little confused about which pictures were the right ones? These are the side-by-side comparisons that you posted Clay...

wickededge wrote:


But then in the post above this one, you had another pic of a the same progression it seemed, ending with 100 passes on the 1m leather strops...


510 x - 1 micron diamond and leather strops after 3.5 micron diamond and leather strops - 100 passes

Unless I missing something, there is a noticeable difference in the first two pictures, but a HUGE difference in smoothness in the last one...

I am referencing post # 2463 & 2464.

In your post above, you've got images from two sets of tests, two on the AUS-8 knife and one on the CPM-154 blade.

Here are three from the CPM-154 knife:

3.5 Micron strops - 100 strokes:

The bevel is very smooth after the 3.5 strops.

1 Micron Strops - both paste and spray - 100 strokes:

There were many, more obvious scratches after adding the spray to the 1 micron strops. I had lost the 'stiction' here and seemed to be getting more abrasion and less burnishing.

1 Micron Strops - both paste and spary - 200 strokes:

I did another 100 strokes with the 1 micron strops after the spray had dried. The stiction returned and the surface smoothed out immediately. I believe that once the spray dried, burnishing resumed and abrasion was minimized.

mark76 wrote:


Well, the whole subject of sub-micron particle stropping has me baffled in more was than one.. I question if it is even possible. See the following chart for a reality check on what worlds of size we are talking about then ask yourself. "what exactly is it am doing or trying to accomplish by putting this size particle on a sample of cow hide and hand applying that to a knife edge".., Hummmm.

Thanks to www.standridgegranite.com/calibration.htm#19 Standridge Granite company for the chart .. There are very few people in the world that know more about "flat" than these folks/. It would be interesting if we could get one of their engineer to participate on this thread !