Lapping film progression
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Personally I have had issues with the lapping film below 3 micron diamond films. I know MarcH has had issue with the film below 1 micron. The 9, 6, and 3 work well for me, the 1.5 and 1 micron I’ve had some success but very erratic and the .5 and .1 no success. those have left scratches that are quite deep and I’ve had to back up all the way to 1500 diamond stone to get them out to try again. My experience with the films is limited!
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Thanks guys. I am also very interested in more experiments some people want to do. Particularly also with other 0.5 and 0.1 lapping films (Jende too?). A problem is of course that with these sizes it is very hard to see these scratch size through a “normal” (up to 200x) microscope. Once I can sharpen again I will also carry out some experiments.
Molecule Polishing: my blog about sharpening with the Wicked Edge
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Welcome to the forum Toolzero!
I happen to use a very similar progression with the films (1500# > 6 micron > 3 micron > 1.5 micron) and I like the results very much, but I’m also not concerned with getting a totally scratch-free bevel. The finish these films leave will have a high polish and will be reflective enough to clearly read text in the reflection on the bevel. The edge will also be very sharp, but the cutting performance does benefit from additional light stropping if you have the option to do so. There’s no need for the 9 micron film when coming off the 1500# stone in my opinion. I actually can’t tell much of a difference between the 6 micron finish and the 1.5 micron finish when examining the bevels without any magnification.
However, if you closely examine the bevels in just the right light you can see residual scratches on the bevel. It is my current opinion that the best way to get (nearly) scratch-free bevel is with the strops. The strops abrade in a very different manner than the diamond films. The strops will take more work and will take some practice to get them dialed in (most people have to use them for a while in order to figure out the right combination of pressure and angle adjustments to get the best results). This is an active are of discussion on the forum right now. If you’re interested in the topic in more detail, be sure to check out MarcH’s recent thread. Marc did a lot of work and documented it all so that we could share in his journey, so it’s a great read.
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Welcome to the forum, Toolzero! I think Organic and MarcH described it well: the lapping films work very well after the 1500 stone. I think it is a matter of personal preference whether you use the 9 micron lapping film after the 1500 stone. I do, since the lapping films work a little different from the stones.
My experiences are that until 1 micron they work really fine.
There have been some doubts here about particularly the 0.5 micron lapping films, but we’re still in a full investigation to see what’s actually going on. Maybe you could contribute to this too… As an alternative, you could of course also use stropping compounds which go even much further in fineness and that do have a good reputation.
Molecule Polishing: my blog about sharpening with the Wicked Edge
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Thanks guys,
I do believe that strops produce not only a sharper edge but a better finish as well. The best overall edge that I’ve been able to produce is a 15 deg. sharpening angle with a 17 or 18 deg. micro bevel and then strop to whatever level you want. My arsenal is 14, 10, 5, 3.5, 1, .5 paste on balsa and leather. I also have the emulsion in 4, 2 on leather. Then 1, .5 emulsion on kangaroo. Then the .25 spray and the .125 cubic boron on kangaroo. Then the .05 and the .025 poly crystalline spray on kangaroo. Especially with the micro bevel stropping is far and away the sharpest and the best looking edges that I can produce.
As far as the scratches go with the .5 and .1 films go I didn’t need a micro-scope. I use a 14x loop and the scratches with that film(.5 especially) was visible with the naked eye. I’m sorry to say that the .5 and .1 films were especially disappointing at best. The only explanation for the deep scratches from the .5 film that I can come up with is the diamonds are clumping together and not staying on the film in a uniform pattern. The scratches are deep and completely random. I purchased all the films from 9 to .1 recently and the 9 thru the 1 micron work pretty well but the .5 and .1 are substandard in my view.
This of course is my experience with the films. Others may have better results with them but for me as of now stropping is far superior…
I have Wicked Edge films in 6, 3, 1, 0.5 and 0.1. I recently picked up a set of Jende films in 9, 6, 3, 1 and 0.5 micron. My results have been much better with the Jende films. I don’t think it’s because they’re better, necessarily. I attribute it to going from 1500 diamond to 9 micron film. That jump seems to be more fluid in the progression.
For what it’s worth I end my progression (after the 0.5 film) with 0.25 and 0.10 Jende diamond emulsion on kangaroo strops. This has worked extremely well.
Clay has provided pretty good evidence that the 6 micron film does a good job of rapidly eliminating the scratches from the 1500# stone. If you read that thread, he even shows that the jump from 1500# to 3 micron film is not entirely unreasonable. Further, Clay has recommended going from the 1000# to the 6 micron film prior to the release of the 1500#.
Those different combinations can be combined and are almost limitless to leave just the right amount of tooth vs refinement. Like you Organic I’m more concerned with the sharpness than completely removing the scratches toward the end of my progression. When the right amount of tooth and refinement are combined the knife will perform for its intended purpose beautifully.
I don’t think it’s been discussed here, but I have frequently thought about what grit progression is most effective. With most increments, I think a ratio of 1.5 to 2.0 is reasonable. For example, going from 3 micron to 1.5 micron would be a 2:1 grit change, while going from 3 micron to 1.0 micron would be a 3:1 change – a little high for my 1.5 to 2 range. Similarly, going from 9 micron to 6 is a 1.5 change, but going from 9 all the way to 3 is a 3:1 change, suggesting that you’ll spend quite a bit more strokes (and time) trying to remove the 9 micron scratches with the 3 micron film than if you’d used the 6 micron in between.
This also seems to apply to the diamond platens as well, but probably more restrictive. Going from 400 grit to 800 grit, a 2:1 change, is going to require a lot more work than going through the more normal progression of 400 / 600 / 800. More important, I think, is the unnecessarily high amount of wear you inflict on the finer-grit stone, or film, as the case may be.
I find that Clay’s recommendation of going from 1000-grit to 6 micron film works very well, although it seems to be a very big step. But if you look at Clay’s grit comparison chart, he lists 1000-grit as 7 microns, which suggests that it’s actually a very small step. Then you wonder, “why use the 1500?” In fact, if you look closely at the scratch patterns for 1000, 1500 and 6 micron, you can see that the progression is appropriate.
I believe that keeping your progression steps to 2:1 or less (1.5:1 or less is preferred) will require fewer strokes at each step and thereby extend the life of your stones/films.
Strops with pastes or spray are different animals entirely. Look at the images for them on Clay’s grit comparison chart and you will see that they polish, rather than abrade. I don’t recall reading an explanation for this, but I think it’s probably due to the fact that the diamond particles are not solidly attached to a platen. They can move and they can be pushed deeper into the strop. They can roll along the surface of the face being polished. None of the particles is held solidly enough to cause the scratches you’d find with abrasive paper or film. Different animal. Different process.
We are still working on the new grit chart, which will make it much easier to identify logical progressions because it will be based on the effects of the medium rather than just the published grit size from the manufacturer. A good example of how this will help are the 1000 and 1500 grit diamond stones. Scratches from the 1000 grit are about 7 microns and scratches from the 1500 grit are about 3 microns.
Strops are a different animal because of the soft substrate and the tight grip they exert on the surface of the metal. Only a small part of the abrasive is in contact with the stone and they are pushed back into the leather rather than the metal of the blade when pressure is applied. There is also my hypothesis that the strops actually burnish as well as abrade the metal so the result is very different from other media.
-Clay
I don’t think it’s been discussed here, but I have frequently thought about what grit progression is most effective. With most increments, I think a ratio of 1.5 to 2.0 is reasonable. For example, going from 3 micron to 1.5 micron would be a 2:1 grit change, while going from 3 micron to 1.0 micron would be a 3:1 change – a little high for my 1.5 to 2 range. Similarly, going from 9 micron to 6 is a 1.5 change, but going from 9 all the way to 3 is a 3:1 change, suggesting that you’ll spend quite a bit more strokes (and time) trying to remove the 9 micron scratches with the 3 micron film than if you’d used the 6 micron in between. This also seems to apply to the diamond platens as well, but probably more restrictive. Going from 400 grit to 800 grit, a 2:1 change, is going to require a lot more work than going through the more normal progression of 400 / 600 / 800. More important, I think, is the unnecessarily high amount of wear you inflict on the finer-grit stone, or film, as the case may be. I find that Clay’s recommendation of going from 1000-grit to 6 micron film works very well, although it seems to be a very big step. But if you look at Clay’s grit comparison chart, he lists 1000-grit as 7 microns, which suggests that it’s actually a very small step. Then you wonder, “why use the 1500?” In fact, if you look closely at the scratch patterns for 1000, 1500 and 6 micron, you can see that the progression is appropriate. I believe that keeping your progression steps to 2:1 or less (1.5:1 or less is preferred) will require fewer strokes at each step and thereby extend the life of your stones/films. Strops with pastes or spray are different animals entirely. Look at the images for them on Clay’s grit comparison chart and you will see that they polish, rather than abrade. I don’t recall reading an explanation for this, but I think it’s probably due to the fact that the diamond particles are not solidly attached to a platen. They can move and they can be pushed deeper into the strop. They can roll along the surface of the face being polished. None of the particles is held solidly enough to cause the scratches you’d find with abrasive paper or film. Different animal. Different process.
Excellent post!
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I do believe you can’t go wrong by overlapping a progression by using very similar grit sizes when changing from one abrasive medium to the next. The grit size may seem redundant but I think the different abrasives scratch differently which helps obliterate the previous scratch pattern. Also the extra step is very quick to do and almost no metal is removed.
Marc
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