Polishing Stones

[guarnera]

I just received two foundation stones from Namikawa Heibei Co. They are synthetic, #80, and #120. They both say in big letters " Carborundum", with "Japan" under that. Then it says, Extra Hard & Fine Stone, with a C80 on one box, and a C120M on the other box. There is a sticker on each box that says Torajirushi #80 on one, and Torajirushi # 120 on the other. Here is my question. How long do I have to soak these stones before using them, and how wet do I keep them while working with them ?

 

Tony G

[Brian Madigan]

I leave mine in water all the time. Generally with new stones I submerge them in the morning and they are pretty well saturated by the time I get to them later that night. Keeping them wet during polishing is a matter of feel I think. I keep pouring water on all the time, but not so fast that it splashes the slurry away. It should be a wet, muddy mess in my opinion.

[John Smith]

I agree with toxonix on that water is your friend while polishing. With foundation stones they need to be clean and clear to keep removing material formthe blade. I am curious what did you pay for them as I am looking for some foundation stones to replace the ones I used up.

[guarnera]

I agree with toxonix on that water is your friend while polishing. With foundation stones they need to be clean and clear to keep removing material formthe blade. I am curious what did you pay for them as I am looking for some foundation stones to replace the ones I used up.

 

 

 

They cost me a total of $110.00 for both stone including shipping. Over half of that was shipping from Japan. I bought these from Hamikawa Heibei Co. Shipping was kind of high, but still not to bad for 2 stones. When I can afford it I'll order a couple of more in different grits.

 

Tony G

[J.S. Hill]

Tony,

 

These are synthetic stones, so you need to be careful not to soak them too much and be careful not to use too much baking soda in your polishing water. The larger the grit, the faster the water penetrates the stone and soaks it down. I would put them in cool, clean water about 1 hour before I planned to use them. It will NOT hurt synthetics to let them dry out naturally between sessions. Too much soaking and/or baking soda will make synthetics break down prematurely. With foundation polishing, the mud does not really help much--it slows down the cutting action of the stone and mars the stroke angle so it is more difficult to remove the scratches of the previous stone. So rinse your stones often. Rinse the stone and keep it well-wetted so it cuts efficiently. Rinse it off every time you splash-off the blade to check your progress.

 

These are VERY rough stones for togi. The 120 g would be close to arato. The 80 g will quickly grind off any ridges (think shinogi) with a miscalculated slip of the wrist, so practice carefully. And the 80 g scratches will be a real pain to remove. Personally, I rarely use a stone rougher than 325 g to start a polish--most of my blades have a 120 grit grinder finish. Regardless, these are very good stones and well-worth what you paid since they will return their cost in time-saved.

 

What did you plan to use to shape the stones???? I like the convoluted flattening stones for rough shaping, and an old diamond bench stone for final shaping.

 

Just my humble opinion, of course. Hope this is helpful.

 

Shannon

[John Smith]

I agree with Shannon on that as to much water is bad but really experience will help you the most learn the stones and the proper way to use them. And yes becareful not to roll the shinogi, once done it is almost impossible to get it back to the original shape.

 

Any how I still plan to buy some in a few weeks just because I will need them soon.

[Brian Madigan]

Thats good info! I didn't think soaking them continuously would effect the synthetic stones. Good to know. Maybe that's why I run through them so quickly. Do you find that the mud fills the stones and prevents cutting at the rougher stages?

Also, Japanwoodworker.com is in california I believe, so shipping should be much less. They have some good Naniwa brand water stones that are a good size, and natural stones which are around 7x2.5".

[J.S. Hill]

Yes. At the higher grits, the slurry falls into the "pores" and clogs them. This makes the stones cut inefficiently AND gouges the steel (especially on the pearlitic structures, i.e. ji), making for a scratch-pattern that is difficult to "read". You ever get up to a harder kaisei and find the ji scratched all up? Didn't see it before? This could be why. This more random pattern also hides any scratches left from the previous stones, so it makes polishing slower. You know--one step forward, two steps back...

 

Soaking them too long will make them wear out faster because it makes the binders loosen up too much and they wear away quickly. Are you finding that you have to re-shape them way too much? That is from too much soaking or a poorly manufactured stone. On the other hand, if you have stones that are too hard, over-soaking will help match them to the particular blade, but at the cost of the life of the stone.

 

I like the Japanwoodworker.com products. I like naniwa okay, prefer bester and Shapton Professional--for foundation, on monosteel, anyways. Yeah, you save a lot on shipping. Especially since we are not talking about swordstones for nihonto. That would be a different story altogether....

 

Hope this was helpful.

 

Shannon

[guarnera]

To All,

Thank you for all your helpful reply's. I probably won't use the #80. At least not till after I try the 120. Yes, I don't want to destroy the thing. Its an 11" Tanto. It has no Shinoki. But I have done that, and it is hard to get back correctly. I just have a small area that I need to remove a bit of metal from. I will be very careful. I plan to get more stones as I can afford it. I will probably get synthetics, since I will only be using them on my own stuff, and not on any antiques. I will probably get a flattening stone or plate from Japan Woodworker. Its next on my never ending list. Thanks again for the help.

 

Tony G

[Arthur]

I use EDM stones from MSC..,,I keep them in water with a little bit of water soluable cutting fluid.....Don't know if this is relative to your question.....just my $.02

[RedNeckLeftie]

Well crud,

 

Looks like I need to pull my Asahi Kongo-do #180, Bester #500, and Norton #1000 from their baking-soda water domains

in order to preserve their lives...

 

Brian K.

 

P.S. Since I work with knife-sized pieces (<6"), I also tend to use the EDM stones (Orange EDM from Boride Abrasives, + the 900F AlOx sticks).

Edited March 22, 2009 by RedNeckLeftie

[guarnera]

Yes. At the higher grits, the slurry falls into the "pores" and clogs them. This makes the stones cut inefficiently AND gouges the steel (especially on the pearlitic structures, i.e. ji), making for a scratch-pattern that is difficult to "read". You ever get up to a harder kaisei and find the ji scratched all up? Didn't see it before? This could be why. This more random pattern also hides any scratches left from the previous stones, so it makes polishing slower. You know--one step forward, two steps back...

 

Soaking them too long will make them wear out faster because it makes the binders loosen up too much and they wear away quickly. Are you finding that you have to re-shape them way too much? That is from too much soaking or a poorly manufactured stone. On the other hand, if you have stones that are too hard, over-soaking will help match them to the particular blade, but at the cost of the life of the stone.

 

I like the Japanwoodworker.com products. I like naniwa okay, prefer bester and Shapton Professional--for foundation, on monosteel, anyways. Yeah, you save a lot on shipping. Especially since we are not talking about swordstones for nihonto. That would be a different story altogether....

 

Hope this was helpful.

 

Shannon

 

 

Ok, I got my flattening stone and Shapton #320 Blue/Black stone from Japan Woodworking yesterday. Trouble is, My wife noticed the box also. And has now forbidden me to spend any more money. Can she legally do that? Never mind. But how is a made tool addict to surport his habit. I've never had to go cold turkey before. I think this may be fatal. I'm scared! I'm cold, I can't feel my legs. O.K. I'll try to get over it, but you may be reading about me in the newspaper soon. Don't be surprized.

 

Tony G

[J.S. Hill]

Tony,

 

Make her a nice hocho, or santoku, and she will hopefully realize the usefulness of your skill and the necessity of the stones. If you get desperate, remind her of her last shopping binge and tell her you were weak. Surely SHE has a passion and can relate. If nothing else works, buy her flowers, clean the house w/o her asking, do up the laundry, and then make her dinner. Then tell her you're sorry. Can't imagine that not working. Of course, she may accuse you of being unfaithful if you go too far! Of course, all legal disclaimers acquitting me of any possible responsibilities for your actions apply here...

 

Shannon

[guarnera]

Tony,

 

These are synthetic stones, so you need to be careful not to soak them too much and be careful not to use too much baking soda in your polishing water. The larger the grit, the faster the water penetrates the stone and soaks it down. I would put them in cool, clean water about 1 hour before I planned to use them. It will NOT hurt synthetics to let them dry out naturally between sessions. Too much soaking and/or baking soda will make synthetics break down prematurely. With foundation polishing, the mud does not really help much--it slows down the cutting action of the stone and mars the stroke angle so it is more difficult to remove the scratches of the previous stone. So rinse your stones often. Rinse the stone and keep it well-wetted so it cuts efficiently. Rinse it off every time you splash-off the blade to check your progress.

 

These are VERY rough stones for togi. The 120 g would be close to arato. The 80 g will quickly grind off any ridges (think shinogi) with a miscalculated slip of the wrist, so practice carefully. And the 80 g scratches will be a real pain to remove. Personally, I rarely use a stone rougher than 325 g to start a polish--most of my blades have a 120 grit grinder finish. Regardless, these are very good stones and well-worth what you paid since they will return their cost in time-saved.

 

What did you plan to use to shape the stones???? I like the convoluted flattening stones for rough shaping, and an old diamond bench stone for final shaping.

 

Just my humble opinion, of course. Hope this is helpful.

 

Shannon

 

 

 

Shannon,

What is the cut off point where you stop rinsing the stone frequently and let a slurry build up? Should I be rinsing to keep the Shapton 320 clean while using?

What grit stone should have a slurry and what grit stones should not? Thanks in advance.

 

Tony G

[J.S. Hill]

Tony,

 

Yeah. Keep the Shapton Pro 325 g. rinsed off as you polish. Anything foundation requires frequent rinsing so the scratch-marks stay consistent and the stone keeps cutting.

 

As far as when to utilize the slurry--that depends heavily on the blade, and the type of polish being done. If you are going w/ a full-stone polish, then about keisei, allow the slurry to begin to build to help with differentiating the ji from hamon. Not too much, or it hides scratches not yet removed by the previous stone. Definitely use slurry for uchigumori. And there is no water w/ fingerstones--you use a paste made by rubbing together very fine uchigomuri w/ some water to lubricate the hazuya as well as the jizuya. This really only works w/ softer steel and is only beneficial to certain softer swords. Might work for 1050 / 1045. Or some home-made orishigane.

 

I don't personally see any benefit for modern monosteel (1075 or higher in carbon). Especially if you are doing a hybrid-polish from koma-nagura up. Will just be more to clean-up w/ the papers. Personally--I find that fingerstones make a monosteel blade just look hazy. Less "clear". Maybe I just never got a good match....

 

Just my humble opinion and personal experience. Hope it helps.

 

Shannon

 

Shannon,

What is the cut off point where you stop rinsing the stone frequently and let a slurry build up? Should I be rinsing to keep the Shapton 320 clean while using?

What grit stone should have a slurry and what grit stones should not? Thanks in advance.

 

Tony G

[guarnera]

Tony,

 

Yeah. Keep the Shapton Pro 325 g. rinsed off as you polish. Anything foundation requires frequent rinsing so the scratch-marks stay consistent and the stone keeps cutting.

 

As far as when to utilize the slurry--that depends heavily on the blade, and the type of polish being done. If you are going w/ a full-stone polish, then about keisei, allow the slurry to begin to build to help with differentiating the ji from hamon. Not too much, or it hides scratches not yet removed by the previous stone. Definitely use slurry for uchigumori. And there is no water w/ fingerstones--you use a paste made by rubbing together very fine uchigomuri w/ some water to lubricate the hazuya as well as the jizuya. This really only works w/ softer steel and is only beneficial to certain softer swords. Might work for 1050 / 1045. Or some home-made orishigane.

 

I don't personally see any benefit for modern monosteel (1075 or higher in carbon). Especially if you are doing a hybrid-polish from koma-nagura up. Will just be more to clean-up w/ the papers. Personally--I find that fingerstones make a monosteel blade just look hazy. Less "clear". Maybe I just never got a good match....

 

Just my humble opinion and personal experience. Hope it helps.

 

Shannon

 

 

 

Thanks for the info. But I am taking your advise and using synthetic stones. Could you tell me what #grit I would start using the slurry. I will be doing a hybred polish. Not all stones. As I don't have but two stones for foundation that are from Namikawa. The rest will be water stones from Japan Woodworker, since I'm just doing mono steel as of right now. Thank you.

 

Tony G

[john marcus]

Well crud,

 

Looks like I need to pull my Asahi Kongo-do #180, Bester #500, and Norton #1000 from their baking-soda water domains

in order to preserve their lives...

 

Brian K.

 

P.S. Since I work with knife-sized pieces (<6"), I also tend to use the EDM stones (Orange EDM from Boride Abrasives, + the 900F AlOx sticks).

 

 

why baking soda ???

[J.S. Hill]

Thanks for the info. But I am taking your advise and using synthetic stones. Could you tell me what #grit I would start using the slurry. I will be doing a hybred polish. Not all stones. As I don't have but two stones for foundation that are from Namikawa. The rest will be water stones from Japan Woodworker, since I'm just doing mono steel as of right now. Thank you.

 

Tony G

 

Tony,

 

At about 1000 grit, allow a mild amount of slurry to help lubricate the stone. Too much and scratches will remain on the nioguchi that you might not see until the next stone. You probably know the drill on that one...go back to the previous stone--maybe even go back two stones. At 1200 grit, the slurry will begin to really show the difference between the ha and the ji. This is helpful ONLY if you are doing a mild etch between grits, because as soon as you put the blade to the 1000 grit papers to begin the hybrid polish, the demarcation made by the stones will be taken right off. So, in a hybrid polish, the slurry really doesn't do anything for the final polish at all, unless you utilize mild etches and do a super thorough job erasing all the scratches with the stones and only use papers from 2000 grit and up. But the polish will really be a slightly different process for each individual blade. Some blades you can't get all the scratches w/ stones, and you'll end up beginning w/ papers at about 500 grit on up. Sometimes the stones in the 3000 grit range smudge too much and don't help. It is different from one blade to the next. But in general, the slurry has no effect on the final appearance of a blade's polish if it is hybrid polished in the end. The slurry just helps to lubricate and to allow you to see the hamon so you can work on different parts of the blade, cataloging as you go in your mind.

 

If you are using stones to polish, you really need to focus less on the slurry and more on the technique. DON'T be rough w/ the blade on the stones. This will tear out the ji and make gouges that are really difficult to polish out. DO all your shaping on the roughest stone possible, but leave delicate areas for the next stone, i.e. mitsukado, tip of kissaki, etc. Work on "reading" the scratches so you know when to continue working a particular stone or when to move on. All these things will influence the look of the polish after using papers much more than whether slurry was utilized or not.

 

John--baking soda makes the water mildly basic and keeps the blade from rusting. Also, the water becomes "slicker" and lends to some mild lubrication on the smoother finishing stones. If the blade is made from pattern welded steel, orishigane, or tamahagane, then kizu may be present. Baking soda-laden water will not penetrate and cause rusting inside the kizu, which would ultimately lead to the blade blistering and rusting from inside-out.

 

Hope that helped.

 

Shannon

[RedNeckLeftie]

Thanks for fielding that Shannon, I'm runnin' a little slow. When I first started polishing--with just water--I actually had blades literally rust before my eyes in minutes (especially bad here in Texas). I don't like using oils, so I found out about adding baking soda.

[guarnera]

Shannon,

Thank you, that's what I was looking for. I fooled around for a few minutes with the Shapton 325 and noticed the difference in color. The first side I did with 120G sand paper, dry. The whole blade came out shinny. I could see the hamon. But the side I started with the stone, the hamon is shinny, but the rest is more a duller frosted gray. I'll let you know how it comes out. Thanks.

 

Tony G