Juuma Cobalt Blue - How to hone Yasuki/Hitachi Steel

[lightfoot]

Honestly I would consider painting the Bevel with a sharpie followed by a few strokes on a 5000 grit stone. If you’re missing the edge by a decent margin there is a possibility that it was honed on tape at some point in the past.

Occasionally these particular Kamisori razors can have oddities in the grind that make getting out to the edge a little bit of a puzzle.

I would definitely try to get some idea as to whether or not someone might have used a layer of tape to overcome this at some point in the past.

I would do this little check first and get back to us here on this thread.

 

[alex1921]

His razor is a NOS(well not anymore since it was honed) Manaslu M500. Those are western style razors.

 

[Patrice]

@lightfoot I realise that my post was confusing.

I have set the bevel on the Shapton pro 1k, I did the overall progression and had a good shave (King 4K, Naniwa Snow 8K, Nakayama, linen, leather, hair test and shave Ok).
I was puzzled that it was unusually difficult to hone on the 1K Chosera and King Hyper 1K hence my question about the stones, I thought maybe this Cobalt stone is much more efficient.
BTW it was OK on the King 4K and Naniwa 8K snow but I'm doing circles on those stones which is more efficient to wear some steel according to my experience than linear strokes.

They say on the website:

"Why Cobalt Blue? Juuma Cobalt Blue stones are made of aluminum oxide and a bonding material. They add a little cobalt to the stones to reduce wear and dishing, and to increase the sharpening speed. You’ll notice this especially if you’re sharpening tools edged with blue paper steel, an alloy often found on Japanese edge tools. The stone simply cuts much better. Cobalt gives the stone its blue colour."

I'll answer other questions after my day work if I can today otherwise a bit later with pictures, I'm very interested in your feedbacks, thank you to all.

@alex1921 It was not NOS but almost. Very good condition, no mark of honing according to my poor expertise.

 

[Patrice]

BTW @lightfoot, what you suggest is certainly what I should have done but I like to restart from scratch.

 

[lightfoot]

BTW @lightfoot, what you suggest is certainly what I should have done but I like to restart from scratch.

I had gotten my hands on one a couple of years ago and for some reason had a very peculiar grind and the actual bevel facet was it a slightly steeper angle than it should’ve been based on its alignment with the spine. I suspect that somebody probably honed with a layer of tape so that was ultimately what I continue to do and I made a big difference in how fast the honed up.

If I recall I believe that was something I got out in front of as soon as I got my hands on the Razor though. Really saved me a bunch of time and steel loss for sure.

I don’t think I ever took that particular razor below 5K to be honest…

Keep us posted!

 

[Patrice]

Hi @Gamma

Western razors are designed to be honed with the spine on the stone. The spine and edge wear identically and this maintains the bevel’s angle. The wear is not damage, its just a wear pattern.

Got it!

I use 3M electrical tape; either Super 33, Super 88, or Temflex 1700.

Thank you, when do you use tape, then? When people ask you to?
BTW I saw on your website you used a Chosera 400 to set a bevel. Is there a particular configuration for this choice?

If you were attempting to set a bevel on a razor using a 1kC and there was no swarf, the issue is your technique, not the brand of stones, or the type of steel, or bevel angle, etc.

I think I have not been specific enough.
When I do my strokes on the 1k, I do like @alx gilmore, linear strokes, 2x10, 2x5, 2x3, 2x2 and then 2x1 two or three times.
I want the razor to cut my forearm hair easily at the end of the 1k process.
Usually I use the King Hyper and I see the color of the steel after the first set of strokes (2x10) I guess.
For this razor, there was nothing.
So I decided to go for another stone to see how it goes, I tried the Chosera 1k - same.
Then I tried the Shapton pro 1K and I quickly saw some steel on the stone (I don't remember number of strokes, etc. but there was a clear difference compared to the two others).
Yet, it has been more difficult to set the bevel than usual, and I remembered I had seen those "cobalt" stones on Dieter tools and was wondering if I should not try them. Hence this initial message.

When I say I used 4 or 5 kapton during the 1k process, I didn't wait that the tape was worn to replace it, it's just that the usual 21 strokes didn't make it even on the Shapton pro.

 

[Patrice]

I had the same razor. I agree that steel is hard but I managed to hone it, probably starting with a chosera 1k then 3k and 8k superstones

It's a great razor, isn't it? I love this brand.
I managed too but I have the impression that it was more difficult then necessary.

 

[Patrice]

Can you show a picture of the razor. I am curious how it looks up close after all these attempts.

Will do tomorrow at sunlight.

 

[Frank Shaves]

How are you lapping the Chosera 1k.

I use a 400-grit diamond plate to lap my Chosera 1k. When I use a 1000-grit diamond plate to lap the 1k, the stone face feels too smooth and does not grab the steel as well as the 400-grit finish.

 

[Patrice]

How are you lapping the Chosera 1k.

I use a 400-grit diamond plate to lap my Chosera 1k. When I use a 1000-grit diamond plate to lap the 1k, the stone face feels too smooth and does not grab the steel as well as the 400-grit finish.

Ah yes interesting. I'm lapping it very thin. First on a glass with 180 grit carbide grain and then with another 1k or directly on the glass. But the Shapton receives the same treatment. I see what you mean though, it's indeed a good way to make a stone more efficient. Other mean is to create a slurry, right?

 

[Gamma]

Thank you, when do you use tape, then? When people ask you to?

I usually don't use tape actually.

BTW I saw on your website you used a Chosera 400 to set a bevel. Is there a particular configuration for this choice?

Was an old video, I haven't had a 400x Chosera in a long time. Typically I don't use anything significantly lower than a 1k to set bevels unless the blade is damaged; rust, chips, frowns, etc.

I think I have not been specific enough.
When I do my strokes on the 1k, I do like @alx gilmore, linear strokes, 2x10, 2x5, 2x3, 2x2 and then 2x1 two or three times.
I want the razor to cut my forearm hair easily at the end of the 1k process.
Usually I use the King Hyper and I see the color of the steel after the first set of strokes (2x10) I guess.
For this razor, there was nothing.
So I decided to go for another stone to see how it goes, I tried the Chosera 1k - same.
Then I tried the Shapton pro 1K and I quickly saw some steel on the stone (I don't remember number of strokes, etc. but there was a clear difference compared to the two others).
Yet, it has been more difficult to set the bevel than usual, and I remembered I had seen those "cobalt" stones on Dieter tools and was wondering if I should not try them. Hence this initial message.

When I say I used 4 or 5 kapton during the 1k process, I didn't wait that the tape was worn to replace it, it's just that the usual 21 strokes didn't make it even on the Shapton pro.

Counting strokes to hone is not really a good plan. I would suggest finding another source of bevel-setting information. You can't set a bevel, or hone, in an optimum sense, by counting anything. It doesn't work that way. I mean, you can count all you want but the number of strokes has absolutely nothing to do with what the condition of the bevel is. I've had bevels that needed 20 minutes of continuous intense honing on a 1k without interruption except to clear the stone; hundreds of passes. About 90% of the time someone contacts me with honing issues, they are a lap counter and don't understand why their bevel isn't set after 75 passes on a 1k. The only real 'method' of setting a bevel is to just set it and when it's done it's done and it ain't done until it's done. Learn to set a bevel so you can shave with it, then you're 'there' or at least very close.

As I mentioned earlier, if you are honing on a 1k Cho/Pro and there is no swarf, it's not the steel or the stone, it's your technique.
When asking or seeking help in these threads, being specific is advisable.

 

[Patrice]

The beast...

 

[Patrice]

Counting strokes to hone is not really a good plan. I would suggest finding another source of bevel-setting information.

Would be thrilled to see some links.

You can't set a bevel, or hone, in an optimum sense, by counting anything. It doesn't work that way. I mean, you can count all you want but the number of strokes has absolutely nothing to do with what the condition of the bevel is.

I get it, I guess it's pedagogical to present it this way and it makes sense + it works very well on "easy" blades. But when it's more difficult it requires more finesse.

I've had bevels that needed 20 minutes of continuous intense honing on a 1k without interruption except to clear the stone; hundreds of passes.

I would think that in that case the problem is that the stone is not adapted to the steel and I should either use coarser stone or a more efficient stone such as DMT or Naniwa Diamond stone. At my very early beginning, I tried to set a bevel on a French vintage razor, it was very hard too. I have set the bevel on my DMT fine stone and it worked well. I didn't dare to it on the M500 because it's too precious and I didn't want to try anything bizarre. But I still have the question in my head and I'd love to read your reasons for doing it this way.

About 90% of the time someone contacts me with honing issues, they are a lap counter and don't understand why their bevel isn't set after 75 passes on a 1k. The only real 'method' of setting a bevel is to just set it and when it's done it's done and it ain't done until it's done. Learn to set a bevel so you can shave with it, then you're 'there' or at least very close.

That definitely makes sense and I can sense the experience here. I would love to be able to do it this way. That's how I try to do for the knives I hone for some friends. I only take a Tiger 220 and do it on the 220 from bevel setting to finishing (it's not for art it's for day to day kitchen job) and I find it very satisfactory to be able to deal with it with a minimum of tools.
When I do my progression, I pass the hair test with the 4k + leather but not with the 1k. That's a good challenge, though. Here again if you have some advice for some videos, I'd be thrilled to try it on my Grelot honing test razor.

As I mentioned earlier, if you are honing on a 1k Cho/Pro and there is no swarf, it's not the steel or the stone, it's your technique.
When asking or seeking help in these threads, being specific is advisable.

Yes, sorry about that, I popped in with a hey guys what do you think of this stone without questioning my technique. Beginner error, won't do it again!

 

[Patrice]

@Gamma OK I have found some stuff to read

Bevel Setting | TomoNagura.Com | Keith V. Johnson

Some think the finisher is the most important stone. Factually – sharpness and smoothness is established at the bevel-set stage.

www.tomonagura.com

There's a lot of very interesting articles, it's a mine!
I'll dig into it.
If you had a specific video to suggest for bevel setting, I'd be happy to have some guidance, there's so much to see.
Thank you for sharing.

 

[Gamma]

Would be thrilled to see some links.

I get it, I guess it's pedagogical to present it this way and it makes sense + it works very well on "easy" blades. But when it's more difficult it requires more finesse.

Counting laps is guess work, regardless of difficulty level. Unless you can tell by feel that the edge is where you want it, it's just guessing that it is done.

I would think that in that case the problem is that the stone is not adapted to the steel

Nope. Besides lap counters and their inherent honing quandaries, knife guys are the second biggest milieu to struggle with razor honing. It makes sense because the thinking is very different on both sides of that fence. We are honing a razor, not sharpening a chef's knife. Most of the time we have all of 18-20mm of blade width to work with. Minimizing wear and focusing on smoothness are two main facets of the job. A steak doesn't care how the edge feels, my face does. Honing razors on very coarse stones can be done, but with extreme care, and skills are needed to not create issues. Normally, it's best to stay around 1k for most work and only going lower when absolutely necessary. Sometimes, it takes time to sneak up on the edge. When I have a very difficult blade I will drop down in grit but it will still take time to get things done sometimes. We can't use the same levels of pressure to cut, like with knives - we have to balance the equation. Diamond plates and very coarse stones leave deep fingerprints that can run below surface level. So sometimes things take longer to do, it's just the nature of the beast. The only real point in any of this though, is there there is no formula. Things are done when they are done. Someone counting 20 laps may miss the edge's max because that blades needed a few more minutes to level the feedback out. It's not a linear equation, things do not follow a previously prescribed progress.

 

[cugel]

I don't count on any stone. There are too many variables: steel, razor's condition, pressure, torque, skill, stone's condition (loaded up with swarf?, freshly lapped?, water vs. oil?). I am sure I am overlooking some.

 

[Patrice]

All this makes sense, I get it that being fast in the first step may make it more difficult for the rest of the journey and is not necessarily the good approach.

It's not that you guys like when it's tedious!

And about torque, if I may ask, is it a shared practice? I have the feeling that it's adding a layer of difficulty because it's already difficult to be even on the whole length of the blade but if in addition I have to torque I fear that I may not be able to be qualitative enough and that it may be counterproductive, like putting too much emphasis on a portion of the length of the blade and creating an irregular bevel.

 

[Darth Scandalous]

All this makes sense, I get it that being fast in the first step may make it more difficult for the rest of the journey and is not necessarily the good approach.

It's not that you guys like when it's tedious!

And about torque, if I may ask, is it a shared practice? I have the feeling that it's adding a layer of difficulty because it's already difficult to be even on the whole length of the blade but if in addition I have to torque I fear that I may not be able to be qualitative enough and that it may be counterproductive, like putting too much emphasis on a portion of the length of the blade and creating an irregular bevel.

You need enough torque to ensure that the bevel is making good contact with the stone all the way to the apex. Too much, especially on a thinly ground blade, will actually flex the apex off the stone. It comes with practice. Using a Sharpie marker to ink the bevels will show you how you are doing.

 

[JPO]

I have the feeling that it's adding a layer of difficulty because it's already difficult to be even on the whole length of the blade

I don't own a single razor I can lay flat on the stone and go up and down. Even if the geometry was perfect, I would hone in a frawn if I did, because you will get more wear in the middle. You can see this as you lap the stone. The stone wears more in the middle.
Torque is used to shift the pressure down to the bevel, and direct it along the bevel. This can be judged by the undercut of water as you shift the pressure.

 

[Patrice]

I don't own a single razor I can lay flat on the stone and go up and down. Even if the geometry was perfect, I would hone in a frawn if I did, because you will get more wear in the middle. You can see this as you lap the stone. The stone wears more in the middle.
Torque is used to shift the pressure down to the bevel, and direct it along the bevel. This can be judged by the undercut of water as you shift the pressure.

Ah yes I can relate, and it's annoying especially for the nose which is not as sharp as the middle (I don't use the heel that much). So it does not come from the geometry and it can be solved by torquing the razor. Is that correct?