# Stone powder for polishing



## Thpp9 (Oct 8, 2021)

I want to give natural stone powders a try and I found from some EU vendors Uchigumori powder and a Hitohira branded Awasedo natural powder. 

Do you have any input about those powders and how I should use them?

Thanks in advance!


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## esoo (Oct 8, 2021)

This will give you a bit of an idea.


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## Thpp9 (Oct 8, 2021)

esoo said:


> This will give you a bit of an idea.



Thanks! That clears up how to use it!


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## riba (Oct 8, 2021)

And another link



The Hitohira poeder just arrived at my doorstep


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## Knivperson (Oct 8, 2021)

Thpp9 said:


> I want to give natural stone powders a try and I found from some EU vendors Uchigumori powder and a Hitohira branded Awasedo natural powder.
> 
> Do you have any input about those powders and how I should use them?
> 
> Thanks in advance!


Why the one over the other?


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## Thpp9 (Oct 8, 2021)

riba said:


> And another link
> 
> 
> 
> The Hitohira poeder just arrived at my doorstep



Thanks for the video. What is he applying as a lubricant? What I've seen normally is water, but this liquid doesn't seem like water to me. Is it tsubaki oil?


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## Thpp9 (Oct 8, 2021)

Knivperson said:


> Why the one over the other?


Uchigumori costs like 50€ vs the Awasedo which costs 12€. If they can both polish nicely, saving some cash would be nice lol


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## Knivperson (Oct 8, 2021)

Where do you buy each from?


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## Thpp9 (Oct 8, 2021)

Knivperson said:


> Where do you buy each from?


Uchigumori from cleancut and Awasedo from karasu-knives. Haven't find anything any other EU vendor selling powder. JNS sells fingerstones but shipping is expensive just for fingerstones. Definitely there gonna be some guy on Instagram that sells for a decent price, but haven't found something


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## riba (Oct 9, 2021)

Thpp9 said:


> Thanks for the video. What is he applying as a lubricant? What I've seen normally is water, but this liquid doesn't seem like water to me. Is it tsubaki oil?


It is water (according the description)


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## EricEricEric (Oct 9, 2021)

Don’t buy it unless it’s dirt cheap, you can make your own stone powder from any stone, even synthetic

It’s only good for adding final effects


This knife is for sale


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## riba (Oct 10, 2021)

riba said:


> It is water (according the description)


I just realized you probably just played the movie in kkf. Head over to YouTube and read the description


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## migwal (Oct 10, 2021)

EricEricEric said:


> Don’t buy it unless it’s dirt cheap, you can make your own stone powder from any stone, even synthetic
> 
> It’s only good for adding final effects
> 
> ...


That’s awesome! How exactly would one make powder from a stone?


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## EricEricEric (Oct 10, 2021)

I would recommend a diamond plate to produce the slurry

This way you can make a powder out of any stone that you want






migwal said:


> That’s awesome! How exactly would one make powder from a stone?


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## drsmp (Oct 10, 2021)

The downside to a diamond plate is one spec of diamond grit in your stone mud will ruin a polish. I now use a similar grit stone or nagura to make mud for polishing


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## EricEricEric (Oct 10, 2021)

It’s really easy to use your fingers to feel through the mud, also you can use a worn down diamond plate or any other medium, endless solutions really


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## migwal (Oct 10, 2021)

Oh okay, so you’re mainly using mud then, as opposed to a dry powder. I was imagining chipping bits of stone off to put in the coffee grinder hana. Thanks!


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## Thpp9 (Oct 10, 2021)

Wait, we take grind the whetstone while it's dry, right? At least that's what I did and then collected the dust, placed it on my bevel, sprayed some windows cleaner on it (like the IG post above) and rubbed with some cotton pads. Pretty decent results honestly


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## EricEricEric (Oct 10, 2021)

That could be another solution, nothing wrong with trying new things 



migwal said:


> Oh okay, so you’re mainly using mud then, as opposed to a dry powder. I was imagining chipping bits of stone off to put in the coffee grinder hana. Thanks!


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## esoo (Oct 10, 2021)

Thpp9 said:


> Wait, we take grind the whetstone while it's dry, right? At least that's what I did and then collected the dust, placed it on my bevel, sprayed some windows cleaner on it (like the IG post above) and rubbed with some cotton pads. Pretty decent results honestly



That's what I've done. A 1K King and a diamond plate to grind it


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## BoSharpens (Oct 11, 2021)

I have bought 1 micron aluminum oxide polishing "compound" and I know the diamond producers sell the stuff. I bought various diamond dust grit sizes in heavy oil from mold base maker DME for the last 50 years. I am sure all forms from garnet to iron oxide to aluminum oxide to diamond dust are available from industrial suppliers as various industries including jewelry making need that stuff all the time.


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## Grayswandir (Oct 12, 2021)

migwal said:


> That’s awesome! How exactly would one make powder from a stone?



You can just save the honing liquid beneath the stone with some plastic wrap. Wait for it to dry out and you have Jnat powder.


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## BoSharpens (Oct 12, 2021)

Grayswandir said:


> You can just save the honing liquid beneath the stone with some plastic wrap. Wait for it to dry out and you have Jnat powder.



The only problem with saving "grit" from a polishing stone is that the particle size is NOT CONSISTENT.

You will have some large particles that 'broke off' of the edge or a small pocket in the surface of your sharpening stone and you really, really don't want those to scratch your finely sharpened edge when you go to polishing. 

Manufacturers of lenses and fine machined parts that are polished buy consistently graded particle size lapping abrasives from companies that specialize in those abrasives and they are worth the small amount of $s you have to pay for them to know you are getting exactly what you want. 

1 oz of 1/2 micron aluminum oxide powder is $6 from: Abrasive Powder

It is worth it to me to get graded polishing powders, though I often use diamond dust.


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## Grayswandir (Oct 13, 2021)

BoSharpens said:


> The only problem with saving "grit" from a polishing stone is that the particle size is NOT CONSISTENT.
> 
> You will have some large particles that 'broke off' of the edge or a small pocket in the surface of your sharpening stone and you really, really don't want those to scratch your finely sharpened edge when you go to polishing.
> 
> ...



That is a good point, but if you're using Jnat powder, the particles break down as you work them anyway, so the particle size isn't stable, just as you mentioned. The Japanese have been polishing blades for centuries, it's never really been a problem for them. I'm sure they've used powders at some point, but most of what I've seen them use is finger stones for the final polish.

I think you make a good point in regards to uniformity in particle size. Jnat particles break down, but they're unique. Most of the abrasives we use, synthetic especially, don't break down like Japanese natural stones do, or at least that's what I've read and heard. There are surface changes to the particles though, there's always going to be some degredation of the particles when you're using them to lap or polish something.


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## BoSharpens (Oct 14, 2021)

Agreed on grit breakdown, but we don't want a large "chunk" to wind up putting a new deep groove in our finished blade before the polish.


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## Grayswandir (Oct 14, 2021)

BoSharpens said:


> Agreed on grit breakdown, but we don't want a large "chunk" to wind up putting a new deep groove in our finished blade before the polish.



Yeah, definitely not. I agree with you, for what you want to do, your powder has to be pristine. no contaminants at all. I saved a little powder about a month ago. I had to lap one of my natural stones flat, so I saved as much run off as I could. All told, I think I have somewhere around a gram or so of powder. It could be more, I don't have a scale to weigh it. I'd like to run a few tests to see what type of finish it leaves. The stone is an Ohira, hardness is supposedly around 3-3.5.

I really need to buy an Atoma diamond plate (more then one actually). I don't like lapping on glass and sandpaper. It works, but I don't think sandpaper is recomended for naturals or synthetic stones. The manufacturers always mention flattening stones on other stones, or using diamond plates. Apparently the sandpaper can make a stone too slick, or leave behind contaminants. I did use ceramic sandpaper, I'm not sure if it's better then silicon carbide or not, or if it leaves less of itself behind then the carbide does?


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## BoSharpens (Oct 14, 2021)

I bought a 5 pound bottle of aluminum oxide polishing powder from a lens supply company decades ago, & used it for decades, but forgot their name. I know companies have commercial processess to segregate by grain size and guarantee their lapping powders to lens grinding & polishing operations. Wouldn't be surprised to see such on the likes of Norton Abrasives.

In the tool shop we lapped stones and tools on a finely ground cast iron lapping surface plate with crosshatched grooves on one side & smooth on the other. Any time you needed a finer flatness, you put it back on the surface grinder and took off another few thousandths of an inch.


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## Grayswandir (Oct 14, 2021)

There's a vendor on Etsy (a shop named TomoNagura) that sells lapping powder (silicon carbide) in many different grits, from 80 grit up to 1000 grit I think.


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## migwal (Oct 15, 2021)

If I was after more of the hazy finish that naturals provide, would it be better to use a natural stone powder over aluminium oxide or silicone carbide stuff? I would think they’d give you more of a mirror polish finish.


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## EricEricEric (Oct 15, 2021)

Here, use this one and you can add stone powder with it 



Amazon.com


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## migwal (Oct 15, 2021)

Nice one, cheers. I found that exact product on Amazon.com.au (I’m in Australia) and it’s only triple the price! You guys are lucky over there. Might be worth a shot tho, I had ok results using my homemade king 1000 powder…


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## Grayswandir (Oct 15, 2021)

BoSharpens said:


> I bought a 5 pound bottle of aluminum oxide polishing powder from a lens supply company decades ago, & used it for decades, but forgot their name. I know companies have commercial processess to segregate by grain size and guarantee their lapping powders to lens grinding & polishing operations. Wouldn't be surprised to see such on the likes of Norton Abrasives.
> 
> In the tool shop we lapped stones and tools on a finely ground cast iron lapping surface plate with crosshatched grooves on one side & smooth on the other. Any time you needed a finer flatness, you put it back on the surface grinder and took off another few thousandths of an inch.



Hey Bo,

I just found out that Jnat slurry particle size does NOT break down as we work the slurry. This a myth and was proven incorrect with an electron microscope. I guess it's what I get for repeating things I've heard from other people, yet never actually saw any evidence or proof that the statement was true.

Here's the evidence:

Does Jnat Slurry Break Down?

The work comes from a really fascinating blog called "The Science of Sharp". Funny enough, I've had this site saved in my browser for over a year, but just started reading his blog on sharpness/keenness a day ago. The information is interesting and very fascinating. He carries out a lot of interesting experiments. Is it scientific? I'd say it is, but he's not carrying out controlled studies or anything. It's just there for the average person to check out and learn from.

As for Jnats, there's definitely something happening when you work the slurry and the blade long enough, but it's not being caused by the abrasive particles breaking down and becoming smaller. It could be the natural binder, pressure, and other parameters, I just can't say with any certainty what's truly going on.

Maybe the particles are getting polished as the slurry is worked? I'm not a scientist, so there's only so much I can offer in regards to this subject.


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