A theory of how the WE diamond pastes work

[wickededge]

I also took a couple of pictures by request:

510x – 1 micron with scale

510x – .5 micron with scale

This was a challenging set to take and I’ll have to try again to get more contrast and visibility with the scratches.

Attachments:

• 1micronwithmeasurementsA.jpg
• 5micronwithmeasurements.jpg

-Clay

[Mark76]

Great pictures again, Clay. And a lot. You must have had a fun night :lol:.

How many strokes did you do with the polishing tapes? If you did a large number, the results surprise me as well. (Well, I almost get used to stuff not working as expected according to grit size.) You might get clearer results if you made scratches (almost) perpendicular to the scratches of the 1000 grit stones. Or did you do this already? (In which case I am not surprised, but flabbergasted :woohoo:.)

After getting the edge to 3.5 microns, I then went back to the polishing tapes:

510x – 3000 grit polishing tapes after 3.5 micron strops

510x – 7000 grit polishing tapes after 3000 grit tapes after 3.5 micron strops
I need to do a lot more work playing with the polishing tapes!

Yes, you cannot write them off that quickly. But this doesn’t look encouraging. The scratch pattern is… well, it’d hardly call it a pattern :(. I think you need a set of somewhat even and repetitive scratches for the tapes to be abrasive in an effective manner.

Now on to 1 micron diamond and leather after the 3.5 micron diamond and leather:

510x – 1 micron diamond and leather strops after 3.5 micron diamond and leather
Looking good!

That is definitely looking good! Which 1 micron compound did you use?

I find these two pictures very interesting:

Then jumped straight from the 1000 grit diamond to the 3.5 micron diamond and leather strops:

510x – 3.5 micron diamond and leather strops after 1000 grit diamond stones

100 passes with the strops after the stones.

I again re-did the edge with the 1000 grit stones before skipping straight to the 1 micron diamonds and leather strops:

510x – 1 micron diamond and leather strops after 1000 grit diamond stones
100 passes with the strops after the stones.

It seems the 3.5 micron compound causes a little more burnishing than the 1 micron compound. Not a lot, since 200 stropping strokes with the 1 micron diamond compound seem to create a better result than 100 strokes with the 3.5 micron compound. But still, the stiction is different.

I also took a couple of pictures by request:

510x – 1 micron with scale

510x – .5 micron with scale

This was a challenging set to take and I’ll have to try again to get more contrast and visibility with the scratches.

Thanks a lot :-). I am working on the scratch sizes as you might have seen. When I make pictures like these myself, one where the edge is almost white and another one in which the edge is quite dark, I find it very difficult to compare them. The scratches also seem different. How do you deal with this (other than by making the photographs again)?

Molecule Polishing: my blog about sharpening with the Wicked Edge

[wickededge]

I’m definitely going to redo the lapping film tests, starting from a polished edge and count strokes and possibly alternating stroke directions, maybe from polished down through 7k to 3k and then back up. I rotated the scope to get the dark and light images in an effort to see the scratches better but wasn’t very satisfied with darker image, have to keep experimenting with it. As far as the ‘stiction’ of the different strops goes, I think it might be a function of how much paste is on the surface and how much moisture it has.

-Clay

[Josh]

Whoa! New scope Clay? Nice pics… what is it?

WOW! Those are some interesting photos and observations Clay! It would seem that there is no sense in going 10>5>3.5>1 when you get the same, if not better results with just going straight to the 1m! Is this observation correct?

Next I wanted to see how the bevel turned out going incrementally but using the same number of passes as the direct 1000 grit to 1 micron test before, so I re-did the edge once more with the 1000 grit diamond stones and then did 100 strokes each with 10 micron, 3.5 micron and 1 micron diamond and leather strops for a total of 300 passes:

510x – 1000 grit diamond> 10 micron> 3.5 micron> 1 micron – 100 passes each

To compare, here again is the 1000 grit to 1 micron:

510x – 1000 grit diamond> 1 micron – 300 passes

Also, it seems as if, when you started w/ the 1k grit and on you weren’t really hitting all the way to the edge of the edge, am I right?

BTW, Clay, which knife is that a pic of? I am curious as to how hard that Aus 8 steel is on the HRC scale…

Thanks for checking on the lapping film… still curious as to what your further testing will reveal 😀

[wickededge]

That’s a good question and I’m not sure I’ve discovered an answer yet. I’d like to do a lot more testing because I don’t think I controlled the experiment enough. I think I need to at least repeat it but perform the exact number of strokes with the 1000 grit stones. I think I may not have done enough strokes with them when I rebuilt the bevel each time which could be skewing the results. You can see in the first 1000 grit picture that I didn’t do enough strokes to reach the edge, so I’ll repeat and see how it turns out. I’ll also need to control for age of strops and amount of paste applied.

The new scope is the Dino-Lite AM-413T5. I’m really liking it so far!

-Clay

[Mark76]

As far as the ‘stiction’ of the different strops goes, I think it might be a function of how much paste is on the surface and how much moisture it has.

That is a good one. In my experiences the leather strops usually work a little better than the balsa strops for burnishing. However, I had one case in which the balsa worked better. That might be the reason.

I tried, by the way, to increase the stiction of a leather strop by making it wet. Not the slightest effect. Next up is stropping with chewing gum on balsa :lol:.

Molecule Polishing: my blog about sharpening with the Wicked Edge

[wickededge]

As far as the ‘stiction’ of the different strops goes, I think it might be a function of how much paste is on the surface and how much moisture it has.

That is a good one. In my experiences the leather strops usually work a little better than the balsa strops for burnishing. However, I had one case in which the balsa worked better. That might be the reason.

I tried, by the way, to increase the stiction of a leather strop by making it wet. Not the slightest effect. Next up is stropping with chewing gum on balsa :lol:.[/quote]

Totally funny. I just redid some of the tests and the role of stiction seems to be huge. I’ll post more below.

-Clay

[Josh]

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!

[wickededge]

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.

Attachments:

• 7000gritafter1micronpolish.jpg
• 3000gritafter7000grit.jpg

-Clay

[wickededge]

Okay, back on track now… Returned to the 1000 grit stone, worked the stone until I reached the edge:

510x – 1000 grit diamond stone – 150 passes

Then I took the 1 micron strops and completed 300 passes:

510x – 1 micron diamond and leather strops after 1000 grit diamond stones – 300 passes

There was an extreme amount of stiction with this strop, much more so than with the others, most likely because it’s the one seeing the most action. Pushing the strop against the blade was causing the Paperstone base to lift with each stroke.

Attachments:

• 1000grit150passes-1stround.jpg
• 1micronafter1000grit-300passes-1stround.jpg

-Clay

[wickededge]

Back again to the 1000 grit diamond stone for another 150 passes:

510 x – 1000 grit diamond stones – 150 passes

510 x – 10 micron diamond and leather strops after 1000 grit diamond stones – 100 passes

510 x – 3.5 micron diamond and leather strops after 10 micron diamond and leather strops – 100 passes

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

There was a very marked difference in resistance from the different strops with the resistance from the 1 micron set being by far the highest.

Attachments:

• 1000gritafter1micron-150passes-2ndround.jpg
• 10micronafter1000grit-100passes.jpg
• 3.5micronafter10micron-100passes.jpg
• 1micronafter3.5micron-100passes.jpg

-Clay

[wickededge]

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

Attachments:

• 1micronafter1000grit-300passes-1stround.jpg
• 1micronafter3.5micron-150passes.jpg

-Clay

[wickededge]

So far, it seems like we’ve confirmed that the best stropping effects come from burnishing, which happens when there is adequate ‘stiction’. Learning how to get the strops properly seasoned so that they have the right amount of ‘stiction’ is something we should study next.

I deliberately did a few strokes at an angle in the last progression to help us visualize the scratches from the finer strops which opens up a whole line of inquiry: what density of diamonds at which grit provides the best teeth for which jobs?

I’m going to try adding some of Keith’s 1 micron spray to my 1 micron pasted strops to see if I can keep the stiction but add more diamonds. More studies to come!

-Clay

[Josh]

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.

Still curious… which blade is this you are sharpening?

[wickededge]

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.

Still curious… which blade is this you are sharpening?

That’s a blade I designed for hunting that we’ll be releasing soon. AUS-8 steel at 57-58 RHC. It’s nothing fancy, actually a very inexpensive knife that fills a particular need. Details to come soon… 😉

-Clay

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