Opinion please--Gunto w/Old blade?

[rasjid]

Yes, mine is on the left n handle rusty as shown. On the right is someone else in Japanese shop for comparison.
How to stop the rust getting worse? I understand that we should not "clean" the nakago. Maybe preserve it?

[trenchwarfare]

Don't do anything to the nakago. That rust, is considered patina on Japanese blades. It tells you the true age of the sword. Yours has some deep pitting. The nakago should be black, not gray. It has been cleaned. The only thing that is sometimes done, is to burnish the tang, with a piece of bone. This will only remove surface rust scale, so as to be able to read the signature.

[estcrh]

Originally Posted by trenchwarfare

Don't do anything to the nakago. That rust, is considered patina on Japanese blades. It tells you the true age of the sword. Yours has some deep pitting. The nakago should be black, not gray. It has been cleaned. The only thing that is sometimes done, is to burnish the tang, with a piece of bone. This will only remove surface rust scale, so as to be able to read the signature.

Red rust would be undesirable, the nakago should have an age related patina which is a form of oxidation that will not harm the underlying metal, red rust on the other hand is considered to be live and will continue to eat away at the metal underneath until it is stopped.

[trenchwarfare]

Indeed.

[rasjid]

Is there anything i can do? Anyone? To preserve or protect from rust?

Thanks

[estcrh]

Originally Posted by rasjid

Is there anything i can do? Anyone? To preserve or protect from rust?

Thanks

Here is Ian Bottomley's recommended method for treating rust on Japanese armor, you can do something similar with the nakago of your sword,

Use a mixture of boiled linseed oil thinned with white spirit in a ratio of approximately 50 / 50 - it isn't critical. The mixture was applied with a paint brush over a small area and allowed to soak in for a few minutes before rubbing the area with a chisel shaped piece of stag antler.

[rasjid]

Noted. Thank you estcrh.
Will keep the info and will do some testing with other material first.

Regards
Rasjid