First Jnat. It’s gorgeous but I have a few questions.

[MG31]

Hello dear friends,

I’ve taken a hiatus from the hobby, but have since fell off the wagon. I’m looking forward to sharing some new additions with the community once I get this Jnat squared away.

I picked up this Jnat as my first, Ozuku Asagi, as well as a Giyo Nagura (pictures attached). I’ve done a lot of research but I still have some things I have questions on if anyone can help.

1. Should I lap the whole top/honing surface (diamond plate) or should I avoid the stamps? I’d sure like to keep them on, not sure if they’ll completely come off after lapping. Diamond plate is fine to use, correct?

2. Should I lap a flat surface on the nagura or can I use it roughed up on the Ozuku? There are no flat surfaces on it so it’s going to be some work to get a side flat (not happy about that).

3. I have cashew oil en route. When I watch videos, a lot of guys seal all sides of the stones, including the tops. Not sure what the methodology is there, but should I do all surface areas on both the Ozuku and Nagura? Or leave tops unsealed?

4. From what I’m reading on this particular stone, some people just raise a slurry on the Ozuku with a diamond plate and prefer that. I’m assuming that’s fine but just wanted to double check. The Nagura doesn’t have any stamps, so I’m not sure if I trust it just yet (also not happy about that).

I got the stones from chefsknives2go, the Ozuku has a chip on the top near one of the stamps. Is this something to get worked up about? I can easily avoid it and I know natural stones aren’t perfect, but it obviously was not cheap so opinions on that are welcome. Any advice, thoughts, or criticism is welcome. I appreciate it and Happy New Year!

 

[Herrenberg]

Saying goodbye to stamps on the working surface is inevitable.

I'd assume you'd want a flat side to the nagura; I think I'd expect that otherwise, chunks of it might break off. In your position, I guess I'd try it and see, though. Might work just fine.

If you are asking about sealing the actual working surfaces of the stones with laquer: definitely do not do that. Never heard of such a thing, and it sounds crazy. Maybe I did not understand your question.

As for nagura slurry vs. diamond plate slurry, try both and see what you think. There is no universal best answer.

 

[MG31]

Saying goodbye to stamps on the working surface is inevitable.

I'd assume you'd want a flat side to the nagura; I think I'd expect that otherwise, chunks of it might break off. In your position, I guess I'd try it and see, though. Might work just fine.

If you are asking about sealing the actual working surfaces of the stones with laquer: definitely do not do that. Never heard of such a thing, and it sounds crazy. Maybe I did not understand your question.

As for nagura slurry vs. diamond plate slurry, try both and see what you think. There is no universal best answer.

Appreciate the help immensely. I’ll try and flatten that Nagura; I’m going to have to find a means other than the diamond plate though, that’ll be rough on it.

As for the sealing, yes that was my question. I found it strange, but I’ve watched two videos where they seal all sides of the stone. I’m not sure, maybe they just lap it off after for a cleaner look? Anyways I just won’t do that.

 

[MasterOfPups]

I like a slightly rounded surface on the nagura myself. It will still slurry just fine, but is not as likely to stick or scratch your base stone as a flat surface might.

 

[MG31]

I like a slightly rounded surface on the nagura myself. It will still slurry just fine, but is not as likely to stick or scratch your base stone as a flat surface might.

Much obliged, I’ll get working on that soon. Excited to try them out!

 

[gbupp]

There is only one time I would seal the top of the stone, and that is if the stone looks like it is going to crack on the current sharpening surface. If the crack seems fine but you are worried it will expand and you want to get rid of it, you can seal the top and then diamond plate/sic powder your way through it. The lacquer in the crack will reinforce it and ensure it does not spread as you work past it.

Otherwise, I would just seal the sides. Sorry for the little bit of thread necro. I do not think your stone needs the treatment where you seal the top and sand through it. I would do sides and back though.

 

[lloydw]

if you don’t see any fissures on the sides or bottom, don’t stress about sealing it right away - you need to lap the honing surface flat to use - which means your stamps come off. Take photos of the original condition and all stamps for your records.

Nagura don’t need sealing but many do this anyway. With the shape - get a few ‘mostly’ flat edges that enable you to rub without being too harsh in sharp edges making contact - a few flatter sections to rub together is all you need for slurry. Sharp corners could be a concern

 

[MG31]

There is only one time I would seal the top of the stone, and that is if the stone looks like it is going to crack on the current sharpening surface. If the crack seems fine but you are worried it will expand and you want to get rid of it, you can seal the top and then diamond plate/sic powder your way through it. The lacquer in the crack will reinforce it and ensure it does not spread as you work past it.

Otherwise, I would just seal the sides. Sorry for the little bit of thread necro. I do not think your stone needs the treatment where you seal the top and sand through it. I would do sides and back though.

Thanks for the feedback! I’m in the process of sealing it now. I ended up lapping it first, gave it a couple days to dry, then applied the first coat of cashew lacquer (thinned with distilled turpentine). I applied the second coat yesterday, so just going through the motions.

I’m contemplating doing 5 coats….. but mannnn is it a process. The black cashew lacquer is gorgeous though, so I really want to make it pop with a few more coats!

 

[MG31]

if you don’t see any fissures on the sides or bottom, don’t stress about sealing it right away - you need to lap the honing surface flat to use - which means your stamps come off. Take photos of the original condition and all stamps for your records.

Nagura don’t need sealing but many do this anyway. With the shape - get a few ‘mostly’ flat edges that enable you to rub without being too harsh in sharp edges making contact - a few flatter sections to rub together is all you need for slurry. Sharp corners could be a concern

Appreciate it! I posted an update in a reply above with the progress. Yep, I took all photos before, and taking photos during sealing too.

The stone is pretty much flawless. There was a small chip on the top as seen in the original post, but that lapped off which I’m happy about. I’ll post pics up once complete.

 

[gbupp]

Appreciate it! I posted an update in a reply above with the progress. Yep, I took all photos before, and taking photos during sealing too.

The stone is pretty much flawless. There was a small chip on the top as seen in the original post, but that lapped off which I’m happy about. I’ll post pics up once complete.

Nice! Glad its coming along well. Usually the reason why people will seal up their nagura is so they can soak them without issue. Often these are softer stones and can crack apart if soaked and not sealed.

 

[lloydw]

Good luck and enjoy the new stones

 

[MG31]

Nice! Glad its coming along well. Usually the reason why people will seal up their nagura is so they can soak them without issue. Often these are softer stones and can crack apart if soaked and not sealed.

Makes sense! I don’t suspect I’ll seal the Giyo Nagura yet. I’m honestly kind of reluctant to use it as it doesn’t seem like a consistent hardness (based off looks, I may be completely wrong). I may seal if I end up liking it.

In the example of the nagura pictured, do the different areas/colors have different properties /density? I really can’t find any examples of something similar.

 

[gbupp]

Makes sense! I don’t suspect I’ll seal the Giyo Nagura yet. I’m honestly kind of reluctant to use it as it doesn’t seem like a consistent hardness (based off looks, I may be completely wrong). I may seal if I end up liking it.

In the example of the nagura pictured, do the different areas/colors have different properties /density? I really can’t find any examples of something similar.

I am guessing the Giyo is a Gujo nagura, though I've seen Chefknivestogo also sell Chu nagura in this format. Often they aren't very clear about what it is. Either of those nagura, especially the Gujo, tend to be very nice nagura or most general work or the step before the tomo/diamond plate phase. They often soften up *a lot* when soaked, and this results in them performing finer as well. They are worth experimenting with!

 

[MG31]

I am guessing the Giyo is a Gujo nagura, though I've seen Chefknivestogo also sell Chu nagura in this format. Often they aren't very clear about what it is. Either of those nagura, especially the Gujo, tend to be very nice nagura or most general work or the step before the tomo/diamond plate phase. They often soften up *a lot* when soaked, and this results in them performing finer as well. They are worth experimenting with!

Fantastic information, thank you! It did soften up a lot when I lapped it so that makes sense. Good deal, that makes me feel a lot better lol.

 

[GreazyThumbs]

1.Take pictures of the stamps for provenance, but if you want to use it they are toast. I recommend a 400 atoma lapping plate and or higher if it is in your budget. I have an 800 and 1200 plate for final finish and creating slurry.

2. I would not waste any slurry stone, if your base stone is hard. Soak your nagura in a small bit of water on a flatish side. Then use the same spot to develop slurry. It will naturally develop a flat spot during use. If your scratching your base stone, then you could flatten out a spot.

3. I normally tape the top and seal all sides. Once you are done with your sealing, lap the top and then champfer the edges of the stone. You will be good to go from there.

4. Experiment with both nagura progressions and or just slurry from your basestone. You will not know what your base stone is capabale of until you try it. JNAT slurry is friable and will break down over use. So feel free to work that slurry, in theory it will continue to get finer during use.

For your chip address this after lapping your stone and champfering your edges. See how much is left and you can address with a small file and some sandpaper. I would not try and lap out a small chip near the edge. Just sand below it and it should not impact your honing. It will naturally work itself out as you use and continue to lat the stone.

Congrats on your first JNAT its a beaut, alot of good knowledge in this forum to get you sorted!

 

[Steve56]

Good advice, lap the honing surface and chamfer the efges. If the chip is still there, just smooth the edges of it with sandpaper. You can seal the edges and/or back anytime, just make sure the stone is dry.

I’d lap a spot flat on the nagura, you can use sandpaper on a flat surface if you don’t want to use a diamond plate. I’d also run a piece of sandpaper over all the nagura surfaces, bits of grit could fall off into your sluryy,

Nice looking hones, congrats !

 

[Tomo]

If you want to save the stamps, you could always lap the bottom and make that the honing surface.

 

[alex1921]

That would be way too much work for the generic stamps on the stone. Just lap it and start using it.

 

[cugel]

take a pic of the stamps, lap it, and get honing. The stamps could well be fake anyways. I daresay most stamps on stones are recent. If not there are sure a lot of freshly mined Nakayamas...

 

[gbupp]

take a pic of the stamps, lap it, and get honing. The stamps could well be fake anyways. I daresay most stamps on stones are recent. If not there are sure a lot of freshly mined Nakayamas...

"Fake" is really hard to discern now adays. Is a wholesaler faking the stamp if they have a stockpile of old Nakayama that they mark as such? Difficult to say, but a healthy does of skepticism is always valuable as you can't really authenticate between vendors with old stockpiles honestly marking stock or unknown stockpiles being marked with good names. Just worth noting that newly stamped stones may not necessarily be incorrectly labelled.

It gets even more confusing with the concept in Japanese culture of "naming things for uses" such as Nakayama sometimes being a synonym for good. It's not exclusive to Japan (just as Coke in many places means Cola) but it is a bit more prolific there.