Lifespan Of A Shirasaya?

[general_piffle]

Good evening, I was wondering about the lifespan of a shirasaya? Are they only ever replaced if they become damaged or do they have a certain 'shelf life' where they're fit for purpose and need replacing every 5/10/20 years? Thanks in advance for your advice/insights.

 

[Ken-Hawaii]

An interesting question. I know that a shirasaya's "shelf life" exceeds 20 years, as I've had several blades that have been well-protected in mine for longer than that. Shirasaya are usually replaced when a blade is (re-)polished, but I honestly haven't heard of any that were replaced for any other reason besides that & damage.

 

Ken

 

[general_piffle]

Thanks very much for your reply Ken. Out of interest, do you know why the shirasaya is usually replaced when a blade is polished? Thanks.

[Ken-Hawaii]

The first reason is to make sure that the new profile of polished blade is held securely by the new shirasaya, but probably mostly because it ensures that none of the crud that gradually accumulates in the saya (oil, dust, grit, etc.) doesn't mess up the new polish.

 

Ken

 

[Michaelr]

I have a blade that was placed in a shirasaya in 1945 and both still look great.

MikeR

[Mark]

i have had swords in shirasaya 200-300 years old that were fine and still worked.