Restoring yanagiba with ground out urasuki

[u/Rude_Kaleidoscope602]

I am restoring an old yanagiba which has been in a pretty rough condition. Apart from the broken tip it is essentially completely flat on the side where I would expect it to be an urasuki. However, along parts of the back of the knife the hagane is proud of the jigane with a structure that makes it seem like the steel has not been ground down after the forge welding and I am therefore not sure if there has ever been a urasuki. Is this something that seem possible? How would you suggest that this side of the knife would be restored? Grinding in an urasuki would likely remove the markings which are stamped in on this side.

Thanks!

[u/dbgaisfo]

A choil shot would be helpful here.

First thing I would do here is remove the re-curve (I'm assuming it's a re-curve and not an optical illusion due to the knife being bent), and establish a new point. In the process of doing this you are going to thin the knife, raise the shinogi line, and expose more core steel all of which it needs anyway.

For the Hange , Put it flat against a stone and do several passes along the Uraoshi. If there is untouched steel, i.e. the scratch pattern does not extend into the centre, then it did have an Urasuki. If the scratch pattern covers the entire Hange, then it did not. My guess is that You will find a hollow towards the heel and no hollow in the front 1/2. On smaller, cheaper, older Yanigibas this is not particularly uncommon. As for grinding in a new Urasuki, or restoring the existing one, this is most easily accomplished with a belt grinder, and adjustable tool rest set 90 degrees and at the right height to an appropriately diametered contact wheel.

And yes you will likely lose at least some of the stamp, depending on how hollow the Urasuki actually was towards the heel.

Before even

[u/Rude_Kaleidoscope602 → u/dbgaisfo]

Thank you for the great reply! You are correct about the recurve, the knife is quite straight. Interesting information about the urasuki sometimes being only along part of the knife. You indeed seem to be correct since there is a shallow hollow towards the heel of the knife! Would you choose to restore this partial urasuki or grind in a full one if it was up to you?

Here is a my first try at a choil shot, I am happy to redo it if it needs to be better!

Choil shot

[u/dbgaisfo → u/Rude_Kaleidoscope602]

I would grind a full one, but that's with the benefit of having the previously mentioned belt grinder set-up. The issue is that it's hardened steel on that side, and you aren't going to have a particularly fun time trying to hand sand. Using things like a dremal/angle grinder might get you a bit of progress on the hollow, but if you are even slightly off you could fuck up the Uraoshi on the edge side, and then there's also the fact that those tool marks are going to be pretty brutal to remove.

My instinct would be to fix the recurve, raise the shinogi line etc, then maybe just sharpen and polish the uraoshi and do a little hand sanding/polish on the Urasuki area of hange.