Yakut - For the ethnic series

[Niles]

I have recently started investigating and making Yakut (or possibly Saha) knives, and am ridiculously impressed with their performance. Consequently, I think it'd be a great addition to the ethnic series.

The yakut has a flat face with a groove on one side, and a convex face on the other. This chisel grind thusly makes a knife specifically right or left handed. The hollow on the flat face makes the knife quick and easy to sharpen.

The handles are simple, usually pretty large, with an egg/oval profile.

I have never made a sharper knife. The ease of sharpening a convex chisel grind makes it simple to get a wicked sharp edge.

Below are a couple pictures of one of mine (made from an old file). I'm still learning to make these, so don't take mine as a historically accurate example, but I don't think I'm far off.

[twinboysdad]

Other than blade geometry, seems an awful lot like a Puuko or Nilakka

[Niles]

Yeah. It's the groove and the grind that sets it apart.

[TomAiello]

What is the purpose of the groove?

[J D Wijbenga]

An interesting, purpose, driven design. I to have investigated is a bit. There are some nice youtube video's of this knife style.
https://youtu.be/zXvirUvF3Co

[TomAiello]

I'm wondering if the groove is just a result of being the way that a flat piece of metal got bent into the convex shape for the other side. It's a nice way to lighten the knife, though.

[nicked.onaut]

I suspect it is for the same reason that Japanese chisels have hollow backs. Flattening the entire surface area of a fully-flat back is much more laborious in time and stone-wear than for a blade with a hollowed portion. Quicker and easier when hollow ground.

Some of the wider Japanese chisels will even have multiple hollow grooves, which also makes paring cuts a bit easier espec. past an edge.



Niles, in making your blade from a file, how did you dish out the central portion while leaving the file teeth present?

If one "pounded down" the central portion, one would first have to soften the file, then re-heat treat, aye?

[Niles]

I suspect it is for the same reason that Japanese chisels have hollow backs. Flattening the entire surface area of a fully-flat back is much more laborious in time and stone-wear than for a blade with a hollowed portion. Quicker and easier when hollow ground.

Some of the wider Japanese chisels will even have multiple hollow grooves, which also makes paring cuts a bit easier espec. past an edge.



Niles, in making your blade from a file, how did you dish out the central portion while leaving the file teeth present?

If one "pounded down" the central portion, one would first have to soften the file, then re-heat treat, aye?

As for the purpose of the groove, you've pretty much nailed it's main reason for being, but I think it's also supposed to add strength to the blade...but this may be more wishful thinking than anything.

As I understand it, these knives were historically tempered fairly soft so they were easier to field sharpen.

As to making it...I first forged the profile, but made it skinnier than I wanted the end product to be. Then I hammered the central portion to widen the blade and thin the hollow a bit. Then I put the blade on the step of the anvil and hammered the hollow and made the convexity. After that it's a matter of flattening the parts that needed to be flat.

I was a little disappointed how prominent the file teeth remained, despite the hammering. I suspect they folded over a bit. And, a file doesn't require a lot of pounding to become knife shaped really.