A theory of how the WE diamond pastes work

[wickededge]

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

Attachments:

• 14micronafter1000grit-100passes.jpg
• 10micronafter14micron-100passes.jpg
• 5micronafter10micron-100passes.jpg
• 3.5micronafter5micron-100passes.jpg

-Clay

[wickededge]

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:

Attachments:

• 1micronafter3.5micron-100passes.jpg
• 1micronafter3.5micron-200passes.jpg
• 1micronafter3.5micron-150passes.jpg

-Clay

[wickededge]

Man, that is really weird why the lapping films were so slow working and hardly did anything… I can’t believe it! My assumptions were totally opposite… lol, it seems as if the only way you can get a fast cutting consistant edge at sub micron levels is with the shaptons… I just don’t have a grand to drop on stones right now 🙁

* edit: keep the test coming Clay! lol, there’s gotta be another answer! I haven’t given up hope!

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

-Clay

[Mark76]

So far, it seems like we’ve confirmed that the best stropping effects come from burnishing, which happens when there is adequate ‘stiction’.

+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 :-).

Molecule Polishing: my blog about sharpening with the Wicked Edge

[wickededge]

So far, it seems like we’ve confirmed that the best stropping effects come from burnishing, which happens when there is adequate ‘stiction’.

+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 :-).[/quote]

Can’t wait to see your results!

-Clay

[Mark76]

Interesting experiments again, Clay!

Slight tangent here – polishing tapes… I decided to retest the polishing tapes, starting from a polished bevel and counting strokes, so here goes, working backwards from 1 micron polish:

510x – 7000 grit polishing tapes after 1 micron polish – 100 passes

510x – 3000 grit polishing tapes after 7000 grit tapes – 100 passes

These look better than yesterday’s results but not overwhelming.

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.

Thanks so much for this Clay! It would, in fact, seem as if the 10>5>3.5 progression yields better results in the end… wasn’t so clear in the first one

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).

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

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

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.

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?

Molecule Polishing: my blog about sharpening with the Wicked Edge

[wickededge]

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.

-Clay

[Josh]

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…

So, here are side by side the 1µ – 300 passes and the 10µ -100 passes> 3.5µ – 100 passes> 1µ – 100 passes:

510x – 1µ – 300 passes

510x – 10µ -100 passes> 3.5µ – 100 passes> 1µ – 100 passes

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.

[wickededge]

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.

Attachments:

• 3.5micronafter5micron-100passes.jpg
• 1micronafter3.5micron-100passes.jpg
• 1micronafter3.5micron-200passes.jpg

-Clay

[BassLake Dan]

When I first saw Tom’s microscope photographs of the edge of a knife after stropping with the 14 micron and 10 micron diamond pastes I was baffled…..

But in short I think the following is happening:

• Both the balsa and the leather strops are hardly abrasive by themselves. They do not cause much burnishing by themselves either.
• The strops become effective when loaded with the diamond pastes.
• The diamond pastes cause a lot of burnishing, but hardly any abrasion.

It is the pastes that do the work, not the strops. And these pastes are hardly abrasive, but have a strong burnishing power.

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 http://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 !

[BassLake Dan]

well that chart did not take here on the forum board software, so let me try it again as a JPG..

Attachments:

• micron-2.jpg

[wickededge]

well that chart did not take here on the forum board software, so let me try it again as a JPG..

Thanks for jumping in and for your feedback and healthy skepticism. I took a photo last night of the CPM-154 blade after polishing with the .5 micron strops with a hair from my nephew’s head for comparison:

You can just barely see the faint scratches on the surface and it seems possible to imagine fitting quite a lot of them into the width of that hair.

Attachments:

• withhumanhair.jpg
• with-human-hair-zoom.jpg

-Clay

[wickededge]

Added a couple more with measurements, these are all 500x magnification:

Attachments:

• withhumanhair3.jpg
• with-human-hair-3-with-human-hair.jpg

-Clay

[Mark76]

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 http://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 !

Hey Dan, thanks for the reality check! :cheer: Put our feet on firm ground again :). I’ll think of that hair when I am staring through the microscope at a 1 micron scratch… (Or better yet, make a photograph of the hair after it has passed the hanging hair test ;).)

Molecule Polishing: my blog about sharpening with the Wicked Edge

[wickededge]

Went back to the 1 micron shot with the most clearly defined scratches and added a .050mm scale. A micron is .001mm, so if we can fit 50 of those scratches into the space of that scale, we’re looking good:

Attachments:

• 1micronwithscale.jpg

-Clay

[Author]

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