Corrosion / Rust On Blade

[GARY WORTHAM]

      After 20 plus years of study / collecting, I have a sword in mounts that after 15 years of ownership has developed a light coating of film that looks to be rust on the last 4 - 5 inches of the blade. It cleans off with ease with chogi oil and uchiko, but has reappeared each time upon examination. It is a 1536 koto KIyomitsu that was polished over 20 years ago, and has since my ownership, never been anything but in perfect condition. 

 

     I used a cleaning extension, deep into the end of the saya, and produced no oil residue, corrosion, or contamination. This is a mystery to me, as I have not seen this with any of my swords. My cleaning efforts are routine and spot on.

 

Any and all thoughts and guidance are deep appreciated

[Greg F]

Hello Gary, it may be where and or how you store your swords. If a sword is kept standing up with the tsuka pointing up any moisture may colect in the lower area on the blade. I was having a similar problem and when i got a gun safe and put moisture absorbing products from the local hardware in tha safe with the sword it has sorted the prblem out. The amount and type of oil used can also be a factor. When cleaning a blade the oil all is pushed towards the kissaki so it is important to make sure it is a thin even layer. I hope this helps. All the best.

 

Greg

[Shamsy]

As Greg has stated, a desiccant in a small area will help (moisture hippos from the supermarket (not scented unless you want flowery swords)), or if you're really serious about preventing rust, check out these http://www.zerust.com/diffusers

 

Oh, you said saya... Saya are not ideal for blade storage and don't allow the air to breath, so that could be part of the problem.

[Stephen]

. Saya are not ideal for blade storage and don't allow the air to breath, so that could be part of the problem. 

 

yet swords are stored in saya's for years with no problems 

[Shamsy]

Correct, hence them not being ideal. A shirasaya is the best option.

[GARY WORTHAM]

Ok, took some good advice from some of the NMB folks, and went to Home Depo, also presenting them with the problem.

 

They refered me to their on staff specialist in this type issue who was very knowledge, and full with many similar stories from customers with other items of this type problem.

 

 

His recommendation was a product called DampRid manufactured by Airscapes, which fit nicely into the floor of my safe / vault.

 

If anyone has had experience with this product, I would appreciate their thoughts.

[Ken-Hawaii]

There are quite a few similar products, Gary, but be careful with products like DampRid that collect water, because they will eventually deliquesce. I use a Dri-Rod in my vault (https://smile.amazon.com/DRI-ROD-DR-12-Dri-Rod-Dehumidifier-12/dp/B002A6RSA2), & it's worked well for 25 years. The only downside is that you need to drill a hole in your vault, but the trick is to remove the power plug, stick the cord through a 1/4" hole, & rewire the plug. If it works in Hawaii's tropical humidity, it should work anywhere!

 

Okay, that said, I keep my lower-value blades in an Edo-era katanadansu, & have never seen a bit of rust - those old workmen knew what they were doing!

 

Ken

 

[Gordon Sanders]

After all of this being said, what is the ideal humidity to keep the swords in?  I live on Hong Kong island at the base of the mountain. Two dehumidifiers run continuously to keep my humidity at approx 40-50%.  Some days they can each pull out about 1 liter or more.  

 

Will this be a good humidity level?

 

My swords are still having the Koshirae being made by Hans, so I don't have any direct experience

[Ken-Hawaii]

We've given up on trying to dehumidify the whole house, Gordon, as we live across the street from the Pacific Ocean. We kept the closet with the katanadansu as dry as possible with a dehumidifier, but after Sears recalled three of our devices in a row, we said the hell with it. And I honestly haven't seen any sign  of rust on any of my blades. I don't have a hygrometer that will fit inside my vault, & so don't know what the RH is inside there. I don't have an answer to your question, although it's a good one. I did find a note that the NBTHK Japanese Sword Museum keeps its blades at 55% humidity and 78° Fahrenheit (22.5° C).

 

My katanadansu looks a lot like this one (http://www.ebay.com/itm/Japanese-Katana-Samurai-Geisha-Zen-Tansu-Box-Wood-chest-Cabinet-Furniture-RX-/182222745650), but cost a whole lot less. I got it from an NMB member, BTW. A shirasaya is supposed to give humidity protection to a sword, but as I don't leave my blades sitting out with just shirasaya, I wouldn't bet on it if you have a decent blade. Guido, what do you use? You're in the tropics, too. This (http://www.ebay.com/itm/Japanese-katana-sword-wooden-case-Tansu-Chest-W110-H15-D16cm-EMS-1week-arrive-/152038020694) looks like it could work, but as you live in Hong Kong, Gordon, where anything can be made, you might want to ask around if something like either of those could be made reasonably.

 

Of course the best protection is a light film of oil, but you probably knew that.

 

Ken

 

[Guido]

I did find a note that the NBTHK Japanese Sword Museum keeps its blades at 55% humidity and 78° Fahrenheit (22.5° C).

 

Actually the NBTHK/Sword Museum keeps the blades below 55% RH, and at about  21° Centigrade - that's why you should wear a sweater when visiting them  .

[drbvac]

I have one of the electric heater rods in the bottom of my storage / display case and the humidity is never above 50% and it seems to be fine - too dry and you will have problems with the saya as they get too dry they can twist and warp or crack. I found for the cost they work very well. 

 

Why the stupid pic is sideways is beyond my computer skills 

[Ruben]

Hi Gary,

 

is the sword mounted with a soft metal tsuba?

 

Greetings

 

ruben

[Alex A]

Impressive display Brian, I tried sort your pic but it did same with me lol

[Brian]

Fixed the pic. iPhones (and other cellphones) leave certain EXIF info that cause them to rotate depending on various unknown factors and how the pic was taken. This is something that is camera related, not forum related.

People need to try and open pics in an image editor, and you will see it is rotated. Open in image editor, rotate, save and upload. Like I just did

[GARY WORTHAM]

Greetings to Ruben,

 

The tsuba is Moyomama and iron.

[Ruben]

Ok Garry,

 

thank you for posting a picture.

I often questioned my self if soft metal like shakudo or copper alloys cause some damage to iron or steel if its conducted.

But obviously not, or not much in long term.

 

Greetings

 

ruben

  Abducted

[GARY WORTHAM]

Ok, got the DampRid from Home Depo, and been using in the sword storage area for about 10 days.

 

Brought out the problem sword blade for examination and cleaning; seems to be the answer and solved the problem.

[Greg F]

Hi Gary glad to hear it. Its a good idea to keep eye on the Damprid as it can be dry for a while then seem to gather moisture suddenly. Enjoy.

 

Greg