Nakago care

[drbvac]

In the hundreds of documents including one from NBTHK on care of swords many mention applying oil to the tang. Considering one thing often used to date swords we are holding for the present time is the level and color of rust on the nakago, how will that practice affect those caring for these a century from now?

 

I would think if not stopping the rust it will certainly affect the rate at which the tang oxidizes so it could remove appearance as a criteria for dating and in fact may account for the appearance of newer swords that have been oiled in the last hundred years.

 

Just wondering if others oil the nakago?

[Stephen]

Just wondering if others oil the nakago

 

Yes, very gingerly. Its a age old issue youll hear from both sides im sure.

[drbvac]

I know Stephen , that said as I pmd to Guiseppe who PM'd me I wonder if that could account for the fresh appearance of some Shin-shinto blades? It would throw me off for sure if someone had actually kept tangs from aging as you would expect.

[nagamaki - Franco]

Hello Dr.,

 

I won't speculate on how things will go 100 years from now as I have enough trouble just speculating about today . The objective of applying oil to the nakago is not to disturb and/or prevent continued aging (black rust) from occurring, but rather to arrest active (red rust) from beginning or advancing. An already healthy nakago coated with a fine layer of black rust only requires careful vigilance. When there is evidence of "active red rust" apply a light coat of oil to the area in question as described in the article of how to care .... written by the NBTHK, leaving just a thin film of oil to prevent oxygen from reaching the metal surface giving the black rust time to take over. If this is done properly the natural aging process continues with hardly any notice that oil was ever applied. Heavier active rust on the nakago is a different story, requiring experienced attention and even professional help.

[nagamaki - Franco]

I know Stephen , that said as I pmd to Guiseppe who PM'd me I wonder if that could account for the fresh appearance of some Shin-shinto blades? It would throw me off for sure if someone had actually kept tangs from aging as you would expect.

 

Hello again,

 

What you're discussing here can be a real problem. Some owners have the misconception that things are supposed to look "as knew". This is true of both nihonto and tosogu as well, in fact we see the results of this behavior at times on items posted here. Education is one answer to the problem. When in doubt leave it alone .

[drbvac]

Thats great advice for almost any situation - known in dentistry "if it aint broke - don't fix it!"

[Ted Tenold]

The objective of applying oil to the nakago is not to disturb and/or prevent continued aging (black rust) from occurring, but rather to arrest active (red rust) from beginning or advancing. An already healthy nakago coated with a fine layer of black rust only requires careful vigilance. When there is evidence of "active red rust" apply a light coat of oil to the area in question as described in the article of how to care .... written by the NBTHK, leaving just a thin film of oil to prevent oxygen from reaching the metal surface giving the black rust time to take over. If this is done properly the natural aging process continues with hardly any notice that oil was ever applied. Heavier active rust on the nakago is a different story, requiring experienced attention and even professional help.

 

Franco has touched on a good point here; prevention. The care that has been given to nihonto has also, to a greater or lesser extent, been drawn from the centuries and become traditional application as well. That said, we should remember that we live in a time of temperature controlled environments, enclosed transportation, improved roads and buildings, etc., that weren't part of daily life in old Japan. The swords were worn in the rain, snow, heat, humidity, cold. Houses in Japan weren't exactly a testiment of good R-factor insulation. All these things were contributory to the preventative maintenance implemented to prevent deterioration. Foul weather covers, transportation boxes, even lacquered samegawa, ito, and tsubas are examples of protection against the elements. All this considered, I think the swords have survived the centuries amazingly well.

 

So, returning back to the oiling question, putting a light coat of oil on the nakago certainly neither harms the blade, nor prevents the aging process from occuring, though in the latter it likely extends the period of time it takes to acquire that "tincture of time", but that isn't a bad thing.

 

Just as an additional note; for practitioners it's a different story because oiling the nakago inhibits the frictional contact with the tsuka foundation important to retaining the blade. This frictional contact is what keeps stress off the mekugi when everything is properly made and maintained. The Mekugi only prevents forward movement that would break this contact between the tsuka and the nakago. But then deterioration of the nakago of the sword isn't really the first area of concern on a practitioners blade anyways.