Tsuba Patina

[Ken-Hawaii]

I was looking at my tsuba collection this afternoon, & noticed a bunch of tiny pin-pricks of rust on one of them, far too tiny even for my antler & ivory to remove from the stippled surface. No idea how it got that way, because it's been in a closed box for many moons.

 

But that made me think about how to clean/maintain a tsuba, or other tosogu. I've read Jim Gilbert's treatise, & usually take his advice about leaving my tsuba alone, but, in this case, is there anything else I can do? I can't see that washing it would help, & the patina is nice & dark as it is. I could polish with choji to stop the rust from spreading, but that's generally a no-no.

 

Ford? Jean? Grev?

 

[Vermithrax16]

Interested in the response from the go to guys.

[Greg F]

Its a tough call but either very softly wipe with minimal amount of choji or wait till its a little bigger to use ivory. Im interested to see responses also.

 

Greg

[TETSUGENDO]

I live in a climate that has a fair amount of humidity, and I have never experienced rust issues with any of my tosogu.  An application of high quality wax (Renaissance/Museum wax, etc.), and storage with desiccants has served me well. Many of my pieces were waxed numerous years ago and exhibit no problems.  Constant cleaning and waxing is completely unnecessary and only invites trouble.  Re-waxing is only indicated in the case of obvious oxidation of the wax coating, or a displeasing change in appearance.

 

Cheers,

    -S-

p.s.-The only thing I might use Choji oil on, and then very sparingly,  would be a completely unembellisted iron guard.  But, it is my opinion, there are more negatives than positives with its use.

[lotus]

Ken -

 

I have the exact same issue with one of my Tsuba. I recall someone mentioning taking some baking soda and a damp cloth to it. This seems to work when the rust is of the loose type. I have not tried that on my Tsuba yet, but I plan on shortly. I have my doubts it will work as I do not think the rust is of that type.

 

Also, I fear any modern approaches will cause more harm to the patina which would force a need for repatination, which is a tricky business to attempt. Ideally, we would need an approach that removes the rust in those tiny pin-prick sports yet does not harm the surrounding patina.

[Ken-Hawaii]

Patrick, I can't figure out what baking soda would do to rust, although it might serve as a mild abrasive. Chemically, oxalic acid would remove the rust, but I'm pretty sure that the patina would be history, too.

[Guest]

 

 

Incant the mantra "Ford, where are you!!" repeatedly by the light of the waxing moon and all will be revealed.

 

You could also try emailing him......

 

See PM

 

[kissakai]

Hi Ken

I do not have any tsuba with pin prick rust

What does it look like under a loupe?

I would try a photgraph as close as possible then say after 6 months take another photo to see if there is any difference

If there 'growth' then ask the forum again

I put wax on my iron tsuba and Ford hates me doing this but my tsuba are handled my myself and other friends/collectors on a regular basis so better safe than sorry

As far as I know the wax can be removed quite easily

Sorry I can't be of much help

 

 

Grev

[TETSUGENDO]

If the affected tsuba is a plain iron one, the elusive tool you seek may be something as simple as a stiff fine bristle toothbrush.

 

-S-

[sabi]

^^^ This, an animal hair brush works well too.

 

Aside from that, periodic rubbing with a cotton cloth should be all you need to do to maintain an iron tsuba. It'll generally wipe away any tiny spots that may appear in storage, and I'm also a firm believer in taking them out of the box and letting them "breathe" every once in a while. I don't have any hard data to back it up, but I think tsuba boxes are prone to trapping moisture inside them, and from my experience a stable iron patina benefits from a little fresh air.

 

A while ago I had small spots as you describe pop up on a stored tsuba, but the one I had on display in the same room during the same stretch of time was immaculate.

[lotus]

Yeah, baking soda really only acts as a mild abrasive. I tried it last night on my pin-prick rust tsuba and it had little effect.  I am not sure if oxalic acid would remove the patina or not. Worth it to try on a test Tsuba. 

 

While a tooth brush or animal hair brush might work on some having the looser variety of rust, I do not think it would work on mine. As for Ford's opinion on wax, I thought he was pro-Ren Wax?? 

[SAS]

Oxalic acid will definitely strip patina.

[TETSUGENDO]

And, if strong enough, will probably etch the metal as well.

 

-S-

[lotus]

That is unfortunate. What is needed is a compound that will only attack the red rust and leave the patina (inactive rust) alone...

[IanB]

Ken, I once had a helmet that behaved in a similar way. There were tiny rust pits that whatever I did to stop them would persist in producing red rust. I know this is going to sound lunatic, but it may be a living organism. At the Royal Armouries Museum we had an outbreak of what we described as 'concentric rust' that started on a German breastplate in stores. By the time it was noticed it was about 2" diameter and showed irregular concentric growth rings and looked like the surface of a bracket fungus you get on old trees. This prompted a serious search amongst the thousands of bits of armour in stores and yes, we found a few other examples After a great deal of investigation that involved a university (can't remember which), it was found to be a micro-organism that metabolised iron - deriving its energy by converting iron to the oxide. On armour it was easy to just clean it off and wax the area, but it had etched the surface. I suspect the so-called 'spider rust' you occasionally find on blades that form branching patches of dark rust is related.  I am not saying your problem is the same but it is something to bear in mind.

Ian Bottomley

[TETSUGENDO]

Fascinating Ian, "clean it off" in what manner?

 

Cheers,

    -S-

[IanB]

Steven,  I do not know for certain as it was the conservation people who did it, but the usual way is to cut the rust off with scalpel followed by waxing.

Ian

[TETSUGENDO]

Thanks Ian,

 

You've peaked my interest.  I did a bit of research and found that there are numerous  micro-organisms (bacteria and fungi) that 'feed' on iron, the most prevalent of these are Thiobacillus ferrooxidans and Leptospirillum ferrooxidans.  Both of these bacteria, and many of the others (including fungi) can be neutralized with household bleach, and their handiwork removed by mechanical means, or the application of acids.

 

-S-

[Ken-Hawaii]

 

the usual way is to cut the rust off with scalpel

Okay, Ian, now that's a bit different than what I expected to hear! Yes, my tsuba has been in its box for at least a year since I last opened it, but I wasn't exactly expecting a micro-organism to be a suspect for the pin-point rust spots! I assume there would be a "film" of protoplasm on the surface, so, rather than cutting off something I can't see (at least with my 400X microscope), is there a chemical reagent I can use? Something that would kill the organism, while leaving the iron semi-pristine? Prodding around with my scalpel in hopes of attacking an invisible critter doesn't really appeal to me.

 

I do admit that I don't remove all of my tsuba from their boxes as often as I should, if only to admire them. I'll take out one of my Heianjo from time to time, but the other ones don't often catch my attention, which is a shame.

 

I did try the stiff-bristle toothbrush, which "might" have helped, but I should have taken a "before" photo to be sure. For now, the tsuba is in the pocket of the shorts I'm wearing (it's still in the mid-80s out here) so I can rub and fondle the tsuba, which should help keep the patina intact.

[TETSUGENDO]

Okay, Ian, now that's a bit different than what I expected to hear! Yes, my tsuba has been in its box for at least a year since I last opened it, but I wasn't exactly expecting a micro-organism to be a suspect for the pin-point rust spots! I assume there would be a "film" of protoplasm on the surface, so, rather than cutting off something I can't see (at least with my 400X microscope), is there a chemical reagent I can use? Something that would kill the organism, while leaving the iron semi-pristine? Prodding around with my scalpel in hopes of attacking an invisible critter doesn't really appeal to me.

 

 

Ken,

 

As I have stated, if your problem is caused by a micro-organism the application of Chlorine bleech should, in the majority of cases, kill it.  If the problem persists, look to another cause and remedy.

 

Cheers,

   -S-

[SAS]

Bleach will also attack steel. Maybe a weakened solution followed by something to neutralize it, like water and baking soda, might work, but testing on non valuable rusty stuff would be a good idea.

[Vermithrax16]

Sunlight (prolonged) will kill any non-photoautotrophic microorganisms.

[Pete Klein]

Dentists have the best toys:

 

 

Hu Friedy 11/12 EXP (explorer).  Very fine and sharp but you use at you own risk!  They can scratch the patina very easily.

[TETSUGENDO]

Gentlemen,

 

Yes Steve, a Bleach solution of 1part to 10 parts of water, followed by a neutralizing rinse, then a couple rinses in water should suffice.

Finish by heating the piece with a hair dryer till dry, wait several days before applying finish of your choice.

Jeremiah, sunlight would work but can be hit or miss depending on conditions, etc.  A strong ultraviolet light source would be more  efficacious.

Pete, try to keep Puck at bay, dental picks should be left to the professionals.....imagine the ugly possibilities!

 

Cheers,

   -S-

[Ken-Hawaii]

I have an array of dental tools from back when I was making jewelry, & I used a sharp point on one of the rust pin-pricks. Didn't make any difference, as far as I could tell with my loupe, but maybe I scared the critter!

 

I'll try the 1:10 bleach when my wife gets home, & tells me where she stashes it.

[Alex A]

Ken, I once had a helmet that behaved in a similar way. There were tiny rust pits that whatever I did to stop them would persist in producing red rust. I know this is going to sound lunatic, but it may be a living organism. At the Royal Armouries Museum we had an outbreak of what we described as 'concentric rust' that started on a German breastplate in stores. By the time it was noticed it was about 2" diameter and showed irregular concentric growth rings and looked like the surface of a bracket fungus you get on old trees. This prompted a serious search amongst the thousands of bits of armour in stores and yes, we found a few other examples After a great deal of investigation that involved a university (can't remember which), it was found to be a micro-organism that metabolised iron - deriving its energy by converting iron to the oxide. On armour it was easy to just clean it off and wax the area, but it had etched the surface. I suspect the so-called 'spider rust' you occasionally find on blades that form branching patches of dark rust is related.  I am not saying your problem is the same but it is something to bear in mind.

Ian Bottomley

 

I know someone who had a similar problem with one of their swords, spider rust that would return after a polish. Eventually ruined the blade.

 

Ken, im not saying this is whats up your tsuba, but maybe with this one, keep it in an air tight plastic box with desiccants as folk do with troublesome iron meteorites.

[Bazza]

... At the Royal Armouries Museum we had an outbreak of what we described as 'concentric rust' that started on a German breastplate in stores. By the time it was noticed it was about 2" diameter and showed irregular concentric growth rings and looked like the surface of a bracket fungus you get on old trees...

Ian Bottomley

I once saw a sword that had concentric rings of rust as Ian describes.  We thought it was JORIN MOKUME (a ring-shaped grain).  However, when the sword came back from polish it had completely disappeared.  A strange experience and feeling.  For more on jorin mokume see:

 

http://www.sho-shin.com/tokai8.htm

 

https://markussesko.com/2015/05/13/kantei-2-jigane-jihada-2/

(a very good read overall)

 

http://www.shibuiswords.com/glossary.htm

(a good link to brush up on terminology)

 

BaZZa.

[Ken-Hawaii]

Okay, I tried the bleach idea. I left the tsuba immersed for 5 minutes, then used the toothbrush, & back in the bleach solution for another 5 minutes. I rinsed the tsuba under running water for 5 minutes, & then dried it thoroughly with my wife's hair dryer. I was more than a bit surprised to find that almost half of the pin-prick rust spots seem to be gone! I'm going to keep an eye on it for a few days before doing anything else, & have it back in the pocket of my shorts, for now. Pretty darn strange! Thanks, Ian!

[TETSUGENDO]

Ken,

 

Glad to hear that you had some success with the bleach, you appear to have neglected the neutralizing rinse....I suggest you rectify this!

 

-S-

[Ken-Hawaii]

Bleach has a pH of about 12, so all that's needed is a long rinse, which I did, under running water. High pH can cause caustic embrittlement of steel, Steve, but I don't think that will happen with a tsuba. There's nothing special about neutralization, speaking as an engineer.