Newbie: Lapping Film, Ceramics, Mirror edges

Legacy Forum Archive basic-techniques-and-sharpening-strategies
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I’ve been struggling to get a scratch-free mirror edge. I can get an edge that reflects extremely well depending on how you view it - from one angle it looks like a great mirror, reflecting even the texture of a piece of cloth. From another angle, I can see that it is covered with scratches.

I am careful about cross-contamination; I use gun cleaning patches spritzed with 91% isopropyl at least at the end of each stone, wiping up and away. One cleaning use per patch. Oftentimes, I’ll clean the blade at least 2-3 times per grit, and examine my work with a loupe. I make sure the prior grit scratches are all removed when viewed with the loupe.

I spritz my diamond stones with a mixture of water and Simple Green; I do it fairly heavily prior to starting their use, and shake off excess solution. I’m following a hint I got from Wayne Goddard’s book - and at least from a tactile feedback perspective, this works quite well. Likewise, with lapping film, I will use a gun cleaning patch and isopropyl before I start.

I just purchased a set of the 1.4/.6 ceramics to try.

So I used this progression on an already freshly sharpened blade: 800-1000-1500 diamond stones; 9 micron lapping film ; .6 ceramic and I got what I think are odd results: after 1500 I had a nice scratch pattern when viewed with a 12x loupe and bright light; there was one section of recurve that I had to spend a bit more time cleaning up, but when I finished, I was confident of the scratch pattern.

Then I moved to the lapping film, and, like every time the magic started: fairly quickly, as I watched with no magnification, the mirror finish came out. After about 150 strokes, the mirror was about as good as I could get with 9 micron. There were new scratches, but all the old scratches from 1500 were gone. The edge from some angles was mirror-like.

I then moved to the .6 micron ceramic. On the completion very first stroke, the blade was completely covered with new, small scratches. I find it odd that moving from 9 micron to .6 micron would do that; however, I’m new to this, so maybe that’s normal. I thought I’d stick it out and see what happened.

After about 25 minutes of strokes - over 1,000 strokes - the edge was still covered with all new scratches from the ceramic. However: the edge felt like super-slick ice when I used the ceramic on it. Extremely “slick” feel, quite noticeable in tactile feedback.

At that point, I called it a day and started to research what I had observed; I am unable to find anything specifically germane to my observation.

If what I’m observing is the way things are supposed to work, then it would seem that the .6 ceramic might best find a spot in the progression immediately aftet the 1500 grit diamond, and then follow it with 9, 5, 3 micron lapping film, and end with some stropping and very find compound.

Questions: does the .6 ceramic behave the same way for others? Do my thoughts on a new progression make sense?

Finally, any observations about why I’m getting the results I see would be great.

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Getting any trace of all scratches out of the entire bevel is a difficult and timely pursuit. I don’t have enough experience with lapping films to give advice on them. I have done several edges with this progression and very good results… thru 1500 diamond then 1200/1600 ceramic then 1.6/.6 ceramic then leather strop with 4/2 diamond emulsion then kangaroo leather strop with 1/.5 diamond emulsion. Spent about 2 hours on the knives I did with this progression.

The ceramics I have used quite a bit and they don’t really produce a “mirror” finish, more like a burnished finish. The ceramic stones can reduce the scratches from diamond stones but don’t work as fast as diamonds and they do need to break in. They don’t work as well new as they will after you have used them on several knives. Ceramics have not been the most popular stones for most, but I have had very good results with mine all though it took a while to get those results. By stropping you can bring the shine to the bevel and reduce scratching even more all be it they require some time as well. Strops did take some time to figure out, for me at least. The technique, pressure and how much to back the angle off seems to be up to each individual so it took me some perfecting and it’s still a work in progress.

Sorry I can’t be more help with your particular progression.

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Thank you. Generally speaking, I really like the feel of an edge delivered by ceramics, so even if this ends up not working the way I hope I don’t look upon it as money wasted.

At the moment, I remain quite confused about the scratch patterns I am creating. To go from a 1500 grit diamond stone, to 9micron lapping film and get an edge that has controlled scratching and (as you can see from the photo I attached) something approaching a mirror finish, and from the very first stroke with the .6 micron ceramic destroying that finish and creating an edge that is a collection of new scratches makes no sense to me. I really thought that the .6 micron ceramic would, at the very least, not result in backwards steps; I was hopeful that, best case, it could be a way to remove all the scratching from prior grits, leaving me with a nice “blank slate” to work into a mirror finish.

I’m going to play more tomorrow with some other lapping film I have, and also break out some of the diamond pastes. It’s really bugging me that I don’t understand what is taking place. There’s always a reason.

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The progression with the ceramic stones don’t follow necessarily the numbered path that say diamonds do. The ceramics are a different animal. Mine get better with every use but don’t behave the same way as any thing else I have. If I could be so bold as to suggest, use the ceramic stones first and then use your lapping films. I know it doesn’t make sense at first to go from .6 ceramic back to a 6 mic. lapping film but try it and see what you think. I think you will like the result compared to the reverse. The ceramic stones are not a finishing stone for me unless I’m after a purely sharp edge and not worried as much with the cosmetics and I still strop almost all of the edges I do, for sharpness and for cosmetics. I don’t think the ceramic stones will ever give a polished edge like lapping or especially stropping. With all that the micro ceramic stones will get better the more you use them.

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Hi RL,

Ceramic stones have caused a lot of questions with me as well in the past. Waterstones consist of abrasive particles embedded in a binding substrate. Diamond stones and lapping films also contain a lot of individual abrasive particles. It is relatively easy to assign a grit rating (or micron rating) based on the size of these particles, although there are multiple systems for grit rating (even in Japan alone there are multiple grit rating systems).

However, as Sal Glesser (Spyderco) stated: “Most abrasives are measured by the grit size used in the matrix. Our ceramic doesn’t work that way. Grit size is constant.” This caused a lot of confusion with me and after delving into it further, I wrote a blog post about it.

I also wrote a blog post specifically about the WE ceramic stones, including the 0.6 micron stones. My conclusion (and that of others) is that the 1.4 and 0.6 micron stones are finer than the 1200/1600 stones. However, the 1.4 and 0.6 micron stones cause scratches that are in practice close together. I doubt that that particularly the 0.6 micron stones are that fine and I think that in a progression they shouldn’t be used after the 1 micron diamond film, as the name may suggest. I think this is similar to your conclusion.

I’d be interested to know where you think they should be used in a progression. However, take care. Just like diamond stones, ceramic stones need to “break in”, which takes time. Also, it is possible to change their “grit rating” by lapping them with a diamond stone.

And you produced a great mirror edge!

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Mark - thanks for taking the time to comment on my quandary. I’ve read (and read again, and then again!) your blog posts re: ceramics - I found your blog a bit ago and enjoy it immensely. Thank you for the work you put in on it, it is a great resource.

I’ll start with a confession: the Emmie is like a Valley Girl on Saturday night going out clubbing. She has her makeup applied, and she’s good at it - she knows how the light will play off her face, and she covers her flaws. If I tilt the top of the Emmie by, oh, 15 degrees in either direction, all the scratches will show up, kind of like the Valley Girl on Sunday morning: you’ll be willing to chew off your arm to make your escape. It’s that bad; I haven’t brought up this issue, but it is very similar to what Marc posts about here. The only difference is that I get the same behavior with 9 micron diamond lapping film; my progression to get to that point is [low grits as needed] 1000, 1500 (stones), 9micron DLF.

Basically, as soon as the DLF hits the blade, two things happen for me: a whole new set of very fine scratches is developed as the scratches from the 1500 are removed, and the blade takes on a mirror appearance when viewed from the perfect angle. I’ve tried many things, and can’t seem to polish out those scratches: the 5micron DLF doesn’t touch them. A strop with paste doesn’t touch them.

Finally, the 1.4 / .6 doesn’t touch them, and this stone then creates another massive set of scratches which removes what I have of a mirror finish (as photographed).

I was hopeful that I could add the .6 stones into the progression right after my 1500 diamond stones, to clean up the blade from the 1500 scratching, and to leave the blade in better shape for the DLF and then stropping. Based on what I tested yesterday, effectively honing using the .6micron side of the ceramic for about 2 hours, my goal looks further away than ever.

As I mentioned, I don’t believe that I am suffering from cross contamination: I’m careful to keep my DLF clean, employing a combination of a super eraser, followed up by canned air, then 91% isopropyl followed by canned air. I do this cleaning prior to using the paddles with DLF. I have also gone so far as to apply new DLF.

Speaking of Spyderco: I have a Sharpmaker, and I have the Ultrafine ceramic. I’ve never had the UF behave in this manner; I have created a near-mirror finish using a WorkSharp and running a progression up to a 12,000 grit belt, and then hit the blade with the UF, and this has always resulted in improvement.

Time to get back to the sharpening bench and try yet again!

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RL Dubbya, keep at it. It’s not as intuitive as we intuitive individuals would think. Like Mark and SKSharp have said the different media don’t behave in a linear fashion as expected done the grit size range. Every media has it’s own quirky characteristics, if I may. It’s up to you to decide by experiencing this how it works best for you to put it all together to achieve the results you strive for.

First what’s acceptable for me may differ for you. There’s no manual that says do it this way, A to B, 1, 2 3…there are suggestions that work. Grit reduction within a same medium like diamond stones, for instance, pretty much follows an expected progression. Same for a particular kinds of Whetstone, but with more latitude. But when you switch from one media to another and then throw in the ceramics, a totally different beast, there’s no telling what you might experience.

Keep at it. You are making progress. I see it and read it in your posts.

 

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Marc - thanks man. I’m sure this will all come together; I’m pretty good about approaching stuff in an orderly fashion, analyzing available data, and then hitting the problem again to, at least, get more data. I found, in my career working in TCP/IP communications and other IT issues (I was the guy people called when everybody else gave up) that if you keep working your discovery, eventually you get enough data to present a well-defined problem, and the well-defined problem automatically contains the answer as part of the definition.

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Yeah, like Marc and others wrote, it is pretty easy to position your microscope so that you see no scratches anymore, but only light reflection. It takes some experience to position it in such a way that you can clearly see the scratches.

There is one thing I don’t quite understand from your reply. Does the 9 micron diamond lapping film leave similar scratches as the ceramic stones? This is not my experience. I can easily remove the scratches from the previous grit with the diamond lapping films. Of course, these leave scratches, too. Only they’re finer than those of the previous grit. You may have to use a little force, but for me it is pretty easy to remove the old scratches using the diamond lapping films. And then you go to a finer diamond lapping film and I find it pretty easy to remove the scratches from the 9 micron diamond lapping film. And so on. You remove scratches and the scratches you introduce are finer than those of the previous grit. And your edge get more and more of a mirror.