"Mirror" finish

[milkbaby]

I was goofing off looking at knives and saw this pic of a Shiraki forged honyaki from K&S:

As you can see from the photo, it's nicely reflective and shiny but not a "true mirror" finish. I want to finish some monosteel knives with sandpaper and have gone up to consistent 1500 sandpaper grit finish which gave a nice reflective and shiny surface which also is not a true mirror.

So my question is about how high a finish you can get with typical sandpaper? I have 1000, 1200, 1500, 2000, 2500, 3000 grit but any higher it seems I will have to try micromesh pads?

 

[mikaelsan]

i'd hate to give the obvious answer, but if you got it to 1500 already you'd might as well continue and see where the grits up to 3000 will lead you. If you have done a thorough job up to this point, you should be through the worst part
but as you might already know the system we use to count grit is not the same as the Japanese whet stone grit system, once you get past a couple of 100 units of grit, don't remember when, the size of the abrasive particles in the western system starts being significantly smaller then in the Japanese system. Further more the American system is finer then the European at the same grit level.
Point being without having ever tried going that high with sandpaper, let alone fine micro mesh pads, 3000 should be pretty damn fine, i'm guessing that should be adequately high

Seems what i remembered was only half true:
https://www.fine-tools.com/G10019.html

 

[Matus]

I recall that is takes about grit 7000 to get finish where the scratch pattern becomes invisible to the human eye.

 

[HRC_64]

There are some amazing mirror polishes out there for sure,
i'd be curious to hear a japanese traditional sequence.
(and equivalent in sandpapers/etc)

This one looks relatively close to near/actual mirror...

 

[nutmeg]

I was goofing off looking at knives and saw this pic of a Shiraki forged honyaki from K&S:

As you can see from the photo, it's nicely reflective and shiny but not a "true mirror" finish. I want to finish some monosteel knives with sandpaper and have gone up to consistent 1500 sandpaper grit finish which gave a nice reflective and shiny surface which also is not a true mirror.

So my question is about how high a finish you can get with typical sandpaper? I have 1000, 1500, 2000, 2500, 3000 grit but any higher it seems I will have to try micromesh pads?

Not sure but I could bet I see scratches from coarser grit under the #1500.
It is tricky with mirror because one can't really hide the scratches like on a kasumi. There is nothing that can "trap" the light.
On pictures, it's possible but in reality, a scratch free mirror is very time consuming to achieve.
I guess you could have a kind of mirror with #5000 but the problem is to remove every time scratches from earlier stages..

 

[milkbaby]

Not sure but I could bet I see scratches from coarser grit under the #1500.
It is tricky with mirror because one can't really hide the scratches like on a kasumi. There is nothing that can "trap" the light.
On pictures, it's possible but in reality, a scratch free mirror is very time consuming to achieve.
I guess you could have a kind of mirror with #5000 but the problem is to remove every time scratches from earlier stages..

I'm not actually trying to get full mirror, from what I've read it's very time consuming and many people will use a buffer for the final steps, a piece of machinery I don't have. I also don't have fingerstones or diamond compounds. But I'm still curious as to how far to progress with sandpaper and what other people's experience has been. The Shiraki honyaki I posted was an example of how I saw it wasn't really mirror finish. I'm curious if this is the typical finish for many honyaki as sold?

For using sandpaper, I alternated sanding directions switching from left to right about 45 degrees angle to the edge. This way I didn't stop sanding until I no longer saw the scratches from the previous grit because they are perpendicular to the new scratches. Going to much higher grit, I'm not sure at what point it will be difficult to see the scratches, but I definitely could see the difference between 1000, 1200, and 1500 grit scratches.

 

[GorillaGrunt]

The highest grit I ever found sandpaper was Starcke Matador 7000 grit. According to their document here:

http://armes.com.pl/files/STARCKE szlifowanie precyzyjne (EN).pdf

That is 2.5 micron, or around JIS 5000. After that I used micro mesh. If you have a natural stone that produces the finish you want, you can use the mud with a cloth or spent mesh pad or some non-scratching applicator. I got pretty well close to a proper mirror finish this way once or twice, and just the 7000 was darn good, to the point where environmental contamination in the room, loose grit from earlier steps, etc., was blocking further progress.

 

[RDalman]

Really a buffed out 600 will look mirror to most folks. If you got it to 1200, you can finish it shiny from there with buffer or autosol on a rag. I prefer the looks of that kind actually over a obsessively rubbed mirror up to micromesh 12k.