What is the absolutest finest abrasive paper available?

[Zach England]

The finest I have been able to find is 3M's .5µ. Is there anything finer on the market?

I know it is likely rendered moot by the irregularities of the adhesive, film, surface, etc. I know about diamond paste and all the rest of it. I simply want to do an experiment. Does it exist?

Thanks.

Edit: Did I really type "absolutest"?--absolutist? Was Louis XVI into scary sharp?

[Andrew Homan]

Was Louis XVI into scary sharp?

Louis XVI made locks so I don't think that sharp blades were his thing --- however, Dr. Guillotin and his Jacobin pals might have been interested...

[Bill Houghton]

I'm not sure how crocus cloth compares, nor do I know how easy it is to find anymore. At one time, it was the standard for "finest grit" paper, but I may be showing my age for knowing that. I have some from my uncle, and I do know it's fantastic for polishing metal parts with light corrosion to get them shiny without fear of scratches.

[David Gendron]

I know LV sale abrasive paper that is so fine, it is use to remove scratches to planes windows! but I don't know if it would be good for sharpening?

[Joel Moskowitz]

THe finest aluminum oxide available is .1 micron, although we don't stock it below .3
However your point "rendered moot by the irregularities of the adhesive, film, surface, etc." is actually incorrect. The big difference between standard wet or dry paper and lapping film is on 3M latting film the variance of the abrasive, the way it is aligned on the film, the thickness of the binder, the backing glue, etc is strickly controlled. This is why the stuff cuts so fast - there are more grit particales of the same size so more grit his abrading at the same time.

[David Keller NC]

3M makes diamond abrasive sheets down to 0.1 micron. You may have to custom-order them from a distributor:

http://products3.3m.com/catalog/us/en001/manufacturing_industry/abrasives/node_GSPRXK3TN1be/root_GST1T4S9TCgv/vroot_J1299GV0RKge/gvel_C610P3WNN6gl/theme_us_superabrasivescatalog_3_0/command_AbcPageHandler/output_html

[David Gendron]

This is a link to LV, they say that the 12000 is less than .1 micron?! http://www.leevalley.com/wood/page.aspx?c=1&p=62146&cat=1,42500

[Richard Jones]

And my J-knives say a big "Thank you!!" to Joel for stocking a nice supply of the finishing films. I can't imagine needing anything finer than a .3µ

You literally cannot feel the grit and, at least for me, it's even hard to tell which side is the film and which side is the PSA!!!!!!!!

Rich

[Bob Strawn]

The finest I have been able to find is 3M's .5µ. Is there anything finer on the market?

I know it is likely rendered moot by the irregularities of the adhesive, film, surface, etc. I know about diamond paste and all the rest of it. I simply want to do an experiment. Does it exist?

Thanks.

Edit: Did I really type "absolutest"?--absolutist? Was Louis XVI into scary sharp?

There are places (http://www.tomeidiamond.com/) that produce diamond abrasives that are as smaller than 60 atom lumps if you want to go that far. Much smaller and carbon dust can no longer be called diamond.

The finest abrasive that I know of that is in general use is called Linde B (http://www.gravescompany.com/polishin.htm). It is .05 micron. It is aluminum oxide and it is not a fast abrasive. The finest grit sandpaper that I know of, is a hand made one used at one time in optical work by hobby lens grinders, I think for preparing mirrors. It was argued that the paper left more scratches than the abrasive removed at that fineness. I am not sure about the paper, but it was a solid one that was used for cleaning lenses. Distilled water with very dilute hide glue was used to coat the surface with hide glue. The surface was warmed and moistened by breathing on it through a wooden tube. Linde B was then dusted on the paper and then shaken off. The advantage to this method was that warm distilled water could remove all residue.

Linde B has become much more rare and as a result more expensive. At one time it was fairly reasonable. I think you could dust a plain sheet of paper with it and skip the gluing. At these scales, a paper that did not scratch lenses would be required and any pressure you could reasonably feel would probably be excessive.

I got some to experiment with, and the only way that I can tell Linde A (.3 micron) from B is that A is not as slow.

Cerium oxide, (http://www.covington-engineering.com/Lapidary_Polishing_Powders.htm) is for my money The best of the finest abrasives. If you choose to get some, go for the higher grade as there is no real point on being stingy at this level of persnickety sharpening. For the really durable steels however, fine diamond is much better.

Below the .5 micron level odd things go on. In stone and glass polishing, some stones polish better with one abrasive than another. This might nor relate specifically to hardness or sharpness either. As a result, often they discuss the chemistry involved and desire an alkali or acid media. There are however exceptions that show no clear patterns. It may be that Cerium oxide has a better chemistry for steel.


Bob

[Gary Herrmann]

Micromesh is probably the most practical answer, but I'm not expert. I use it on some of my turnings. If you can get a glass smooth finish on wood, I imagine you can do the same on metal - but what do you gain from going that fine?

Didn't know about Linde. Interesting. I wouldn't mind seeing a study of all this ultrahigh grit stuff, but purely from an informational standpoint.

[Zach England]

And my J-knives say a big "Thank you!!" to Joel for stocking a nice supply of the finishing films. I can't imagine needing anything finer than a .3µ

You literally cannot feel the grit and, at least for me, it's even hard to tell which side is the film and which side is the PSA!!!!!!!!

Rich

When i first got the .5 micron paper I was not immediately sure which side was which.

That 30,000 shapton suddenly seems cheaper...

[Bob Strawn]

When i first got the .5 micron paper I was not immediately sure which side was which.

That 30,000 shapton suddenly seems cheaper...

I had exactly the same experience. How can you tell when .5 micron paper, or plastic film, is worn down or clogged?

Bob

[harry strasil]

Roll your own cigarette papers are the finest, that's what they use to polish injection molding dies with.

[Joel Moskowitz]

if you use the finer papers wet - oil is best - they will last longer and clog less.
incidently the sub micron films were introduced to take the place of hand polishing - they are used for example to automatically polish the platters of hard drives.

[Glenn Vaughn]

This is a link to LV, they say that the 12000 is less than .1 micron?! http://www.leevalley.com/wood/page.aspx?c=1&p=62146&cat=1,42500

I have diamond powder for gemstone polishing and .5 micron is 60,000 mesh.

Diamond Powder 0-1/2 Micron 60,000 0-1/2 micron 10.00 CTS
Diamond Powder 0-2 Micron 14,000 0-2 micron 10.00 CTS
Diamond Powder 1800 Mesh 1,800 6-12 Micron 10.00 CTS
Diamond Powder 4-8 Micron 3,000 4-8 Micron 10.00 CTS

[Zach England]

I am starting to think this whole thread is unhealthy and indicates mental instability.

[glenn bradley]

I am starting to think this whole thread is unhealthy and indicates mental instability.

Quite possibly ;-) I have been using .3 micron on glass for my scary sharp setup for quite awhile. It does indeed feel finer than typing paper but, it is a better abrasive.

[Zach England]

OK. Thanks, all. i had forgotten about micromesh. I actually think I have some I ordered and stashed in a drawer somewhere.

[Matt Meiser]

Roll your own cigarette papers are the finest, that's what they use to polish injection molding dies with.

At least that's what the maintenance guys told their boss when he walked in. :D

[Harlan Barnhart]

Quite possibly ;-) It does indeed feel finer than typing paper...
I have heard of people using typing paper for a final strop.

[Jim Koepke]

Roll your own cigarette papers are the finest, that's what they use to polish injection molding dies with.

When I was a smoker, Bugler was my tobacco of choice. I have used many different cigarette papers through out the years and can tell you that some would be rather abrasive and some might not be much more abrasive than tissue paper.

A lot of the papers have clays and other things in their list of ingredients. Some are pure fiber.

I was also in printing paper sales many years ago.

jim

[James Carmichael]

Paraphrasing from a recent thread, how did our predecessors produce such beautiful work without the sharpening technology we have today?

Really, I think too many woodworkers obsess about sharpening to the sub-atomic level, getting the absolute perfect primary, secondary, tertiary, et al bevels, and the bright, mirror finish someone says you should have to keep your edge from simply bouncing off of hardwood.

"Sharp enough" is sharp enough to do the job at hand. I keep pieces of corian in my sharpening drawer loaded mostly with Norton SC paper from my local AutoZone store in grits from 600-2000. I have a few adhesive-backed sheets up to 2500 I bought a few years ago, but other than the convenience of not needing adhesive to stick them, I see no performance difference. The fine grits last a very long time, I replace them when they don't seem to be honing well, or I feel like it.

Before using a tool, I take out whatever grits seem appropriate and hone it. If it's not cutting well enough, or sees prolonged use, I touch it up. Freehand, the bevels on plane irons and especially chisels are plenty long enough to do this with.

Not bragging or claiming expert status, but this works fine for me. I started woodworking about 6 years ago and have spent maybe $60 total on hand tool sharpening equipment and supplies.

[Bob Strawn]

"Sharp enough" is sharp enough to do the job at hand.

Not bragging or claiming expert status, but this works fine for me. I started woodworking about 6 years ago and have spent maybe $60 total on hand tool sharpening equipment and supplies.

I am all for what works for people. I am also all for crazy levels of sharpness. Not that you have to achieve them all the time, but I do like to have all my tools sharper than they need to be, all the time.

Part of the issue here are all the claims of sharpness out there that are plain crazy. It is rather nice to know what sharp really is, so the silly brags can be looked right past.

Of course it is really easy to show what sharp really is. Take a piece of high flint glass. Break it. if you get a nice edge on it, then you will know what sharp is. At this sharpness, the flow of glass will dull it considerably in less than a day. Any claims of sharper than this steel, can be dismissed out of hand.

Bob

[Halgeir Wold]

Supply houses for fiber optic cables should be able to get you .1 micron dry paper. Some years ago when manually connecting and polishing fiber conenctors 0.5 and 0.1 was usually the last step....

[Graham Hughes (CA)]

With the .5µ paper, the best way to tell the abrasive from the film side is the abrasive is actually smoother.

[Mark Stutz]

Of course it is really easy to show what sharp really is. Take a piece of high flint glass. Break it. if you get a nice edge on it, then you will know what sharp is. At this sharpness, the flow of glass will dull it considerably in less than a day. Any claims of sharper than this steel, can be dismissed out of hand.

Bob

Back in the Dark Ages, when I was in college, I did some work with an electron microscope. I suspect things have changed quite a bit, but in order to cut the thiiiiiiiiiiiiiiiin sections, we used a freshly broken piece of glass. Actually more complicated because it had to be exactly right, but it was able to cut sub micron thick sections.

Mark