Yanagiba - WIP

[Cushing H.]

I have long wanted to own a Yanagiba, but never took the plunge. a while ago I bought some 26C3 from AKS with the intent of taking a stab at a Yana. I thought my skills were at a point now that I could take a stab at it ... and so recently profiled it, and today did my pre-HT initial grind on the bevel. Pictures below. the steel is really too short (200mm blade) for a true Yanagiba, and the profile I now see is not really quite there (the spine is straight for too long a stretch - but I can re-profile that down after HT. Mostly I was concerned about trying to keep a clean Shinogi, and it turned out .... not bad. Just a little wave, but I have post HT refinement (and likely EDM stones) to get the final product clean. Will post again later. If this turns out ok - I will likely take a stab at a longer 270mm or so blade
(dimensions: thickness - 0.145 (a little too thick), pre HT edge ~0.024, pre HT grit - 120)

Oh - I do have a contact wheel, but I am not sure at all how to go about grinding a clean concave urasuki on the back of the blade. recommendation would be most welcome!

 

[FredyCro]

You have probably seen Stacey's thread on Yanagiba (very old!). He explains ura there. I think the easiest way would have been a jig and do it while it was still just a bar of steel. I think you could still put in a jig and adjust the angle accordingly, often the ura doesn't exactly follow the line of spine. Mind you, I have no experience what so ever doing this. Looking forward to results!

 

[Cushing H.]

You have probably seen Stacey's thread on Yanagiba (very old!). He explains ura there.

thank you for the reminder. I did look through Stacy's thread - but it has been a while. I will need to review

I am also really curious about the steel also (it does definitely rust while grinding......)

 

[Stacy E. Apelt - Bladesmith]

You will love 23C3 for a yanagiba. It will take a very nice hamon.
At 200mm, I would call it a shobu … which is basically a short yanagi.

 

[Cushing H.]

Thank you stacy. Lol - i have never heard of a a shobu - but i am now so taught! After reviewing your teachings, i am no sure if i want to invest in a radiused platen ... but we will see!

(unfortunately, i still do not have my own ht oven ... so this sample will go to JT!. Perhaps on my (next) longer sample (after i have built my proposed oven) i will experiment with hamon

 

[Stacy E. Apelt - Bladesmith]

For the urasuki, you can try the below "cheat". Results vary with skill and what size contact wheel you have.:
Put your largest contact wheel on the grinder - 10" minimum, but 12" to 16" is better.
Take some scrap steel the same width as the blade and practice this technique.
Hold the steel as if you were going to make a hollow grind down the center of the ura ( back side).
Make a shallow pass.
Turn the bar so it is at a slight angle to the wheel ( lift one end and drop the other). Make a pass. This pass should make a hollow wider than the first. Try various angles until you get the feel of it. When done you usually have to do some cleanup, but the basic metal removal is done.

You can rough the urasuki in with a curved coarse sharpening stone or modified half round metal file.

To finish the urasuki, use sandpaper with a curved wooden backing block.

 

[Cushing H.]

Hmmm. Thanks stacy. Looks like i will need to go get some mild steel bar and see how well i can hold that line.

 

[Stacy E. Apelt - Bladesmith]

Just remember that the urasuki is very shallow. You could leave it off and you would be fine … but where's the fun in that!

I read where a follow in the UK made a radius platen out of wood (Lignum vitae, IIRC) and used it. He sanded the radius by temporarily putting the piece of wood on a 24" board and swinging it back and forth (pivoted on the other end) across a hand held sander. No reason that wouldn't work for a person only doing a couple urasuki a year.

 

[Cushing H.]

Just remember that the urasuki is very shallow. You could leave it off and you would be fine … but where's the fun in that!

I read where a follow in the UK made a radius platen out of wood (Lignum vitae, IIRC) and used it. He sanded the radius by temporarily putting the piece of wood on a 24" board and swinging it back and forth (pivoted on the other end) across a hand held sander. No reason that wouldn't work for a person only doing a couple urasuki a year.

I did see the references to a radius platen from wood - i will try your trick first on mild steel and see what it looks like. If it totally fails i might well try a wood platen (likely just 2x1). Like you said - what is the fun in not trying?

i will definitely wait for post HT though to do anything on the blade

 

[Cushing H.]

Now that I have finished that first "learner" yanagiba (and learned mis-steps along the way), I am going to resurrect this thread for next steps - my "holy grail" of a 300 mm Yanagiba (this time with correct blade dimensions). Given that Yanagiba are usually much less high than my first attempt, here is a proposed profile for a 300mm blade this is meant to follow more correctly the typical profile. 1.4" high at the heel, the tang is 3" long.

Any comments/suggestions for changes? I have the steel in now, so can cut this out any time.....

 

[Daniel Carraher]

I want to tackle one of these soon

 

[Joshua Fisher]

Now that I have finished that first "learner" yanagiba (and learned mis-steps along the way), I am going to resurrect this thread for next steps - my "holy grail" of a 300 mm Yanagiba (this time with correct blade dimensions). Given that Yanagiba are usually much less high than my first attempt, here is a proposed profile for a 300mm blade this is meant to follow more correctly the typical profile. 1.4" high at the heel, the tang is 3" long.

Any comments/suggestions for changes? I have the steel in now, so can cut this out any time.....
View attachment 1695954

My suggestion as far as shape is to slightly increase the length between the machi and the heel and I would tighten the radius of the choil, looks like maybe a 1/2” radius, I’d try a 1/4” or 1/8” radius for a more defined look.

 

[Cushing H.]

My suggestion as far as shape is to slightly increase the length between the machi and the heel and I would tighten the radius of the choil, looks like maybe a 1/2” radius, I’d try a 1/4” or 1/8” radius for a more defined look.

Yeah - I see the more typical smaller radius on the choil. I do have one smaller small roller - i'll adjust the radius so I can use that smaller roller. Thanks.

I'll need to think about/play with whether to increase the distance between machi and heel. I pretty much settled on that distance for my own comfort a year or so ago, and since this blade is for me...... Nevertheless, I will take a second look at how a longer distance feels to my hand.

Thanks again Joshua!

 

[Cushing H.]

I want to tackle one of these soon

It actually was easier for me than I thought it would be. The thicker stock makes it easier to pin the shinogi and keep it straight. grinding the Urasuki also was much easier than I thought it would be .... but you DO need a radius platen to do it.

This is a longer blade - so we will see how grinding it goes. I AM going to try the "metal tab on the tip" approach on this one - it seems like using that will make things much more stable when grinding at the tip....

 

[Cushing H.]

My suggestion as far as shape is to slightly increase the length between the machi and the heel and I would tighten the radius of the choil, looks like maybe a 1/2” radius, I’d try a 1/4” or 1/8” radius for a more defined look.

Ok - I have a 1/4" small roller, and modified the choil to reflect that smaller radius. I like it - thank you for bringing that to my attention!

 

[FredyCro]

It actually was easier for me than I thought it would be. The thicker stock makes it easier to pin the shinogi and keep it straight. grinding the Urasuki also was much easier than I thought it would be .... but you DO need a radius platen to do it.

This is a longer blade - so we will see how grinding it goes. I AM going to try the "metal tab on the tip" approach on this one - it seems like using that will make things much more stable when grinding at the tip....

Since the blade has almost constant width and the tip comes more or less in the middle why not grind/cut the bar to width and do the urasuki on a rectangular bar. Match the rest and center of the knife to the middle of the platen and grind away. With table and push stick you will have the rough hollow in 5 min. Leave about 2 mm on the sides for the finer grits. Grind the tip to shape and flaten the ura side on the coarse diamond plate.

On the first knifemaking course I ever did I wanted to do a deba with ura, so this is also on my bucket list.

What steel are you going for?

 

[Cushing H.]

Since the blade has almost constant width and the tip comes more or less in the middle why not grind/cut the bar to width and do the urasuki on a rectangular bar. Match the rest and center of the knife to the middle of the platen and grind away. With table and push stick you will have the rough hollow in 5 min. Leave about 2 mm on the sides for the finer grits. Grind the tip to shape and flaten the ura side on the coarse diamond plate.

On the first knifemaking course I ever did I wanted to do a deba with ura, so this is also on my bucket list.

What steel are you going for?

Hmmmm. That might well work ... i'll need to think about that. I do all (or most) of my grinding post heat treat, so i would mostly be worried about killing the temper when grinding away all that edge material...

Grinding the ura *really* was easy ... it was just the long lever arm from the handle out to the tip when grinding the tip that made for keeping it centered a challenge. I am hoping that using the "tip tab of metal" will help a lot with this.

This may sound strange ... but i found making this style of knife to be much less challenging than making a long, thin, full flat grind blade. The thick stock makes keeping that relatively short bevel uniform and the shinogi crisp *much* easier, and as i said, grinding the ura was surprisingly easy (not a lot of material to remove, and because you are grinding against a *thick* piece of metal, heat buildup was hardly a concern). That first attempt of mine took so long because other stuff kept getting pushed up as higher priority, not because it inherently took a lot of time itself.

For metal, im using 26c3 at target 65 rhc. I love the stuff. It is well behaved on the grinder, and at 64 that edge......