1000 grit sandpaper and above.

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TL;DR what sand paper do you guys use for blades above going from 1000 grit and above?

I've been working on a bunka honyaki (a medium sized kitchen knife similar to a santoku with a hamon) and I've been stuck on the polishing stage for about 2 weeks now specifically at around the 1000 to 1500 point in my progression.

I've had to start over a couple times because the knife will end up with a random scratch from setting it down, and just handling it in general. So that's part of the problem. The other part of the problem is that the 3m wetordry slows down significantly after 800 grit.

I use 3m cubitron up until 320 grit then go over to 3m wetordry which is fine because I normally don't mirror polish.

I've tried taking it over to the buffing wheels a few times, but even at 1000, and 1500 my coarsest buffing compound seems to have trouble getting the scratches out.

So I'm starting to get a bit desperate now, because I want to move forward with this project. So does anyone have any better >1000 sandpaper, and what does your mirror polish progression look like for hardened steel?
 
If I go 1000, 1500, 2000 Rhynowet, then 4000, 6000 3M polishing sheets, that's pretty much mirror by my standards.
Making a hamon look it's best is another question. Joshua Fisher Joshua Fisher does some at only 400 grit with light high grit polishing between etches and they look great. I did one like that also that turned out well. Nothing to lose by testing, you can always sand it some more.
 
Richard338 said:
If I go 1000, 1500, 2000 Rhynowet, then 4000, 6000 3M polishing sheets, that's pretty much mirror by my standards.
Making a hamon look it's best is another question. Joshua Fisher Joshua Fisher does some at only 400 grit with light high grit polishing between etches and they look great. I did one like that also that turned out well. Nothing to lose by testing, you can always sand it some more.
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Thanks. I might have to get some ryhnowet for the 1000-2500 grits. Then I have some trizact to sand with once I hit 3k.

As far as the hamon. I'm trying to get a specific look from it. I'm going for more like a mirror look you would see on a japanese style kitchen knife, than the untra high contrast, look that you see with western blades. So far I've tried etching at different grits as I progressed up, along with various other things I've tested, and it looks like my best bet might be to do the lemon juice etch method, or to dilute my ferric chloride, and to a light etch.
 
I have used the trizact 3000 and 5000 with the spongy backing. They are nice for lightly removing oxides between etches, but I don't think they would be part of my progression to mirror.
I think you are on the right track. I did a tanto a few years ago that I got to mirror and then used vinegar and lemon juice to slowly bring out a subtle hamon with wispy white aspects. It takes a lot of patience. I had my backing wear through a polishing sheet late in the game and scratch the bevel... devastating.
 
Richard338 said:
I have used the trizact 3000 and 5000 with the spongy backing. They are nice for lightly removing oxides between etches, but I don't think they would be part of my progression to mirror.
I think you are on the right track. I did a tanto a few years ago that I got to mirror and then used vinegar and lemon juice to slowly bring out a subtle hamon with wispy white aspects. It takes a lot of patience. I had my backing wear through a polishing sheet late in the game and scratch the bevel... devastating.
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That's rough. If something like that happens to me I think I'm just going to set down the knife and not touch it for a week while I recuperate. Lol.

Yeah I honestly wouldn't know about the trizact. I had just heard they were good for a progression a while back, but I haven't had a chance to actually use it yet.
 
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Ken H> said:
That's my problem with a mirror finish for anything but a display knife.
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Yeah. It's not really a practical finish by any means. Generally I do satin, or etched and stonewashed finishes.

The only reason I'm bothering with this knife is to fit the style I'm going for. I can't see myself doing something like this again any time soon.
 
The trizact work great to remove oxides between etches if your finish is only 400. I tried it on a 2000 grit finish and it just smeared everything. I was puzzled why Josh likes them, but when I tried it on a 400 finish I could see why.
 
DBFCE825-A2EB-40EB-BC73-C02E7852553D.jpeg
This is a 400 grit finish followed by several short etching cycles, lately I’ve been doing 10-15 second dips in 50/50 Ferric/vinegar between each dip I use a 3000 grit then 5000 trizact pads. Like Richard said they are great for scrubbing oxides off, I wanted a polished low contrast after my final etch I’d use the 5000 again until it’s polished as much as I want, the ashi will go from dark to white. I normal use a automotive compound which keeps the ashi dark.
 
Joshua Fisher said:
View attachment 1860881
This is a 400 grit finish followed by several short etching cycles, lately I’ve been doing 10-15 second dips in 50/50 Ferric/vinegar between each dip I use a 3000 grit then 5000 trizact pads. Like Richard said they are great for scrubbing oxides off, I wanted a polished low contrast after my final etch I’d use the 5000 again until it’s polished as much as I want, the ashi will go from dark to white. I normal use a automotive compound which keeps the ashi dark.
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Joshua Fisher Joshua Fisher that’s gorgeous man. Perfectly executed. Almost looks like a digitized hamon 🤯
 
Get yourself a grit conversion chart so you can tell when "1000 grit" isn't the 1000 grit you expected. ANSI (wet-or-Dry) and FEPA-P (Rhynowet) have different classification systems such that you could easily go backwards in absolute grit when you didn't expect it.
 
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Joshua Fisher said:
View attachment 1860881
This is a 400 grit finish followed by several short etching cycles, lately I’ve been doing 10-15 second dips in 50/50 Ferric/vinegar between each dip I use a 3000 grit then 5000 trizact pads. Like Richard said they are great for scrubbing oxides off, I wanted a polished low contrast after my final etch I’d use the 5000 again until it’s polished as much as I want, the ashi will go from dark to white. I normal use a automotive compound which keeps the ashi dark.
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Yeah I want the white ashi, and also the hagane (I guess you would still call it that on a honyaki) to be mirror finished. Above the hamon, a kasumi like finish is fine. Maybe some light reflectivity.

Maybe today after I get back home ill drop back down to 800 then I'll do some quick etches followed by ppolishing with some higher grits, and see if it gets me anywhere close to where I want to be.
 
Blankblank said:
Yeah I want the white ashi, and also the hagane (I guess you would still call it that on a honyaki) to be mirror finished. Above the hamon, a kasumi like finish is fine. Maybe some light reflectivity.

Maybe today after I get back home ill drop back down to 800 then I'll do some quick etches followed by ppolishing with some higher grits, and see if it gets me anywhere close to where I want to be.
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You will likely need to do some differential polishing, Id start by establishing a good kasumi finish on the entire blade with stones then selectively polishing with finger stones along the edge to get the desired finish. Namikawa Heibei has a good selection of natural and artificial polishing stones for Japanese blades. I’d start there and get some different polishing stones and pastes.
 
Joshua Fisher said:
You will likely need to do some differential polishing, Id start by establishing a good kasumi finish on the entire blade with stones then selectively polishing with finger stones along the edge to get the desired finish. Namikawa Heibei has a good selection of natural and artificial polishing stones for Japanese blades. I’d start there and get some different polishing stones and pastes.
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I have some japanese natural stones, and finger stones. I've literally worn away all of my better synthetics for polishing, right now I'm stuck with a bunch of stones that are good for edges, but not so good for polishing.
 
Blankblank said:
I'm actually getting good results using flitz. I'll update with another picture after a few more rounds of polishing with it.
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It looks really good, if you keep etching and polishing for short cycles it should develop the hamon further. When you are happy go back over with the 3k or a 5k pad then flitz. Usually I do 4-5 cycles but have done as many as 7-8 depending on how the hamon is looking. Keeping each cycle to 10-15 seconds tops helps prevent over etching with a stronger etching solution.
 
Ok, here's what I've got. I'm happy with the amount of definition in the hamon. I did some differential polishing on the hagane with the flitz, probably 4 applications of polish. I might polish further, but I'm really liking the way its starting to look.

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I took pictures from a few angles to give an idea of what it looks like. Not even close to a perfect mirror, but I'm ok with that at this point, seeing the 800 grit scratches is fine. I did my best to keep the scratch pattern consistent before etching so it's not a problem.
 
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