Iron Tsuba , cleaning?

[GRC]

For IRON tsuba, I'm having some nice success with antler.

Don't go anywhere near soft metal inlays with an antler!

Here's about three hours of antler work (before, during, after):

Procedure I used:

1-Did 2 hours of scraping with antler 

   *There was a lot of "bubbly" looking surface rust and crud to deal with

2-Soaked in mineral oil for about 5min

3-Scrubbed tsuba with an old toothbrush to get as much rust-dust off of it as possible

    *Oil "disguises" the rust, so don't fool yourself after the oil & scrub steps, by thinking everything is perfect

4-Wiped/dabbed as much oil away with paper towel so I could see if it needed more work... and yes it did.

5-REPEATED STEPS 1-4 [One more hour with the antler tip to hit target areas, followed by oil soak, toothbrush scrub, wipe with paper towel]

 

Pretty happy with the results so far...

Now one of my other tsuba has a "big brother".

 

[Surfson]

Nice Glen.  It's very gratifying.  I sometimes bring a tsuba to work or while watching TV or whatever, along with some ivory (I find that sometimes antler has some harder inclusions that can scratch patina).  The time goes by faster and there is less suffering if I am distracted by a lecture or a film or whatever.  

[GRC]

Thanks Bob.

It really is satisfying isn't it 

 

I thought I may have gone through the patina in a spot or two on another tsuba, but wasn't sure if it's because the antler had gotten through an area where maybe the rust went deeper into the tsuba? I'm not sure if it works like that because the patina itself is just its own form of oxidation (similar, but different to red rust).

Anyway, I'll have to keep an eye on that in the future, so thanks for tip 

[Surfson]

Yes, I think that ivory may be just a little softer than deer horn, but I'm sure that somebody has measured them, and obviously, ivory is one type of horn!

[ROKUJURO]

8 minutes ago, Surfson said:

 I think that ivory may be just a little softer than deer horn, but I'm sure that somebody has measured them, and obviously, ivory is one type of horn!

Robert,

Ivory is one type of tooth, while deer horn is a kind of bone (basically calcium phosphate). Ivory can have different hardness depending on the location in the elephant tusk. The exterior portion is a bit harder, as far as I know.

[mas4t0]

1 hour ago, Surfson said:

Yes, I think that ivory may be just a little softer than deer horn, but I'm sure that somebody has measured them, and obviously, ivory is one type of horn!

 

Antler and bone are primarily ossein, and have a Mohs hardness of around 5.

 

Ivory, tusk and tooth are primarily dentin, and have a Mohs hardness of around 3.5.

 

Horns and claws are made up primarily of keratin (the protein found in hair, fingernails, and animal hooves), surrounding a core of live bone. Keratin has a Mohs hardness of around 2.5.

 

[JohnTo]

 Sorry I’m a bit late getting into this discussion (poor vision due to cataract surgery).  Simply put, my philosophy when it comes to rust on iron tsuba is that if it is outside the seppadai and can be easily removed with cotton wool, wooden toothpicks and oils, then do so.  IMHO Iron rust scabs allow moisture to remain trapped and if salts (from the general environment, sweat, etc) have also found their way in the iron is going to continue to rust.  Harder objects like ivory, bone and antler may be used for stubborn spots, but nothing harder than that.

I don’t understand why Jim Gilbert has an aversion against cleaning sukashi piercings.  Swords are repolished to remove rust, paintings are stripped of old varnish, museums clean their exhibits.  What is special about tsuba?

While I would not clean sukashi with a file, sandpaper or steel pick (which would damage the patina and expose bare iron), I regularly use a wooden toothpick with a small piece of cotton wool attached or a tooth flossing brush (see pics) with a bit of WD-40 to remove loose (red) rust and general detritus.  Why would anyone want to leave rust, bellybutton fluff etc. (possibly impregnated with soy sauce or other corrosive chemicals) within the piercings?  Most of my sukashi tsuba were obtained from old collections and have obviously been neglected.

I would remind those non-chemists amongst you that the black and brown patinas found on iron tsuba are essentially the same thing as rust (iron oxides).  However, patinas are created in a controlled fashion so that the oxide forms a tight bond with the iron hindering further corrosion.  When bare iron corrodes the rust does not adhere strongly, flaking off, exposing more iron which continues to oxide.  Moisture and ionic chemicals, e.g. salt, getting trapped in the rust will accelerate corrosion.  Remember, rust never sleeps, but removing moisture and salts will slow its progress.

To illustrate, attached is a senbikizaru (1000 monkey) tsuba that had a lot of loose red rust in the sukashi.  I cleaned it using just a toothpick wrapped in cotton wool and a dental flossing brush with WD-40.  I don’t think that I have damaged the remaining patina.  If I find signs of rust reappearing I will repeat the treatment and apply a thin coating of Renaissance wax polish, using a cocktail stick wrapped in cotton wool, which is claimed to be used in many museums.

 

Best regards, John

[JohnTo]

Like most tsuba collectors I have acquired some rusty junk examples.  One that I have been experimenting with is a circular plate tsuba, covered with rust when I bought it as ‘the freebie’ in a mixed lot.  It is round (8.3 x 8.2 x 0.45 cm) depicting a Chinese landscape with figures next to huts and a boat on a lake.  Probably not commercially worth having it professionally restored.

My first stage was to clean the surface with cotton buds soaked in WD-40 to remove most of the red surface rust.  I like WD-40 (the name stands for Water Displacement formula #40) as it was designed for the aerospace industry and seems to be able to seep in between the rust particles and the iron and loosens them enough to be wiped off with a cotton bud.  At this stage the reverse side in particular seemed to have a grey-green colour and this led me to believe that a previous owner had removed the rust  and patina with acid, or Cocoa-cola, but the exposed iron had rusted again.  The little copper and silver tagazogan figures did come up nicely. After this and all liquid treatments I dry the tsuba with tissue (kitchen roll) and leave overnight on a hot radiator.

My next stage was to use WD-40 and penetrating oil, separately, and an old electric toothbrush and this removed more light surface rust (you can see the rusty oils soaking into the kitchen roll) but did not seem to touch the heavy patches.

My last stage was to try Renaissance Metal De-corroder, an amine complex of hydro-oxycarboxilic acid in aqueous solution at a pH of approximately 4.0 (i.e. slightly acidic), applied with a cotton bud.  It is claimed that this material ruptures the bond between the base metal and corrosion layer, reducing iron oxide to sludge, which can be wiped away. Rust was certainly evident on the cotton bud, but a more liberal covering on the more corroded areas together with use of a piece of bone did not get down to base metal.

As the tsuba was effectively junk I decided to try something more drastic.  There were several heavily corroded areas and I dripped some De-corroder on these patches.  I then placed the tsuba in a plastic box (CD case) to prevent the De-corroder drying out and left it overnight.  The areas covered with De-corroder had swelled into a black jelly and wiping this off with cotton buds soaked in water revealed that the rust had been largely removed exposing the bare iron (see pics).  I have not carried out this process any further, but I expect that I could end up with a rust free piece of shiny iron, which I would either protect using Renaissance wax polish, or try to repatinate.

Please note that I am not recommending the use of De-corroder on areas of tsuba that still have some of the original patina.  I have not tried it, but I would expect that long exposure would result in the patina being removed as well as the rust.  Remember, rust and patina are both iron oxides.  However, this product does appear to remove rust from iron while leaving the underlying metal untouched, which is more that can be said for use of hard abrasives or steel picks.

Best regards, John

Pic 1 and 2 Before cleaning

Pic 3 and 4 After WD-40, penetrating oil with electric toothbrush

Pic 4 and 5 before and after De-corroder

 

[ROKUJURO]

Thank you John!

Good examples of corrosion treatments to avoid on TSUBA!

[Bugyotsuji]

At the joint NBTHK meeting yesterday I pulled out an iron Choshu (?) tsuba with some unsightly rust spots, and plenty of heavy gold/silver zogan of grasses, birds, moon, etc., and we had an instant huddle of tsuba afficionados eagerly discussing their methods of rust treatment. What was most apparent was the difficulties involved and the concern that people feel when confronted with the problem.

 

"I mash the rust first with a hammer", said one. "Brass hammer?" I asked innocently. "No, not necessarily."

"After applying some kind of oil?" I enquired. "Oh, no, you must hit/tap it first, and then apply the oil afterwards" came the reply. 

"Hmmm..., horses for courses around here," I thought.

Having listened to all of them, I began to feel fresh hope in my breast. There is no 'Royal Road to Rust Removal', but there are tools and methods and considerations.

 

Before I left, my sword teacher added, "If you get too enthusiastic with the antler or ivory and reveal bright glinting bare iron below, bring it to me and I will repatinate those areas for you."

[Mark S.]

22 hours ago, Bugyotsuji said:

 

…bring it to me and I will repatinate those areas for you."

 

Now THAT would be information this group would find VERY interesting.  

[Bugyotsuji]

Mark, you’d have to go and become an apprentice methinks.