Rusty Moro Kris

[mrwizard]

Recently i rescued this moro kris.
For my untrained eye it looks like Maguindanao and (because the ganja seem to be seperate) before 1900.
The hilt is not original to the blade as i can see traces of previously attached baca-baca in the black rust on the blade. The hilt is wrapped with cotton thread and covered with a kind of natural gum. Not pretty but very functional in my opinion. As the cotton is still white, i believe the blade has never been used after it got its latest outfit.
Compared to my WW2 kris the blade is very light and narrow and it seems to be far better balanced.

When i got it the blade was covered with a layer of active red rust. I carefully removed most the red rust and oiled the blade but as you can see on the photos there is still red rust left in some cavities.
For further cleaning i intend to take chemical measures (pineapple juice or diluted vinegar).
A problem is the hilt. The options as far as i can see is to either remove the hilt or to put the sword in an upstanding tube, so that the hilt is not covered by the solution.
What are your opinions on this matter?

Best Regards,
Thilo

[Sajen]

Hello Thilo,

you are also infected?

I use for cleaning a standing tube (a drain pipe from plastic, sheap to get in a do-it-youself-store, together with a fitting closing) and attach in up a wire. So you are able to hang the blade inside without the liquid have contact with the handle. As cleaning liquid I use lemon acid from the supermarket (it's here in Germany cheaper than pineapple juice and do the same job). When you control it good there is no risk for the blade and it works fast and good. Take it time by time out and pick away the rust with a hard needle. Like this I have cleaned a lot of blades with very good effort.

I agree with you that this isn't the original hilt and there have been two baca-baca. I can't say something to the origin but I am sure that Jose or Kai will be able to determine the derivation.

Regards,

Detlef

[tunggulametung]

Hello mrwizard, I guess different method suit different case but in my opinion you might want to consider "electrolysis rust removal" for this particular case. There are several threads on this forum mentioning this method, or google for it. I've tried this method with much success on keris blade as well as for other purposes (gas tank cleaning etc)

I'm lazy with setup so usually I just use whatever lying around, but a tube should be good idea for broader item like this particular.

When we mention the word rescue/preserve I guess we should avoid acid as much as possible. I consider myself as conservative but I really don't look into fruit acid anymore.

I'll post result on keris if needed.

Note: this method did not remove pitting, it will expose good metal/anything below the rust, and also keep in mind that you need to gently scrap/brush the left over carbon into beautiful shiny metal after the process.

Good luck if you consider this method

[tunggulametung]

On my second thought I really encourage any member who has not try to look into this method. I think I really should post before and after picture, and I'll do that tomorrow.

[Spunjer]

Yes, look into that process, the electrolysis method. Check out my post "winter project". It does wonder...

[mrwizard]

Thanks a lot for all the interesting input.

@Sajen
Yes, i fear i'm infected... and all because i was looking for a new pocket knife...
The advice of using citric acid instead of pineapple juice is very good. I'm always reluctant to waste the delicious juice.

@Tunggulametung & Spunjer
Electrolysis is of course a very gentle and elegant method of rust removal. On the other hand it is always a big mess and takes some extra effort.

The kris blade has a surface of roughly 400cm^2 if i assume a current density of at least 20mA/cm^2 this would require 8A and for ramp up and closure of the process i would need to be able regulate that current. My lab power supplies won't do, so i would have to build a custom one (not a big deal for me but still some effort).
What current density did you use for your winter project, Spunjer?

For now i still think fruit acid is the most appropriate way to go as the rust isn't as bad as on Spunjers kris. But i will look further into this topic. I have time the kris won't rust away within the next days...

...and if i'm really infected as Sajen said, building a custom power supply will quickly pay off

Best Regards,
Thilo

[tunggulametung]

Originally Posted by mrwizard

@Tunggulametung & Spunjer
Electrolysis is of course a very gentle and elegant method of rust removal. On the other hand it is always a big mess and takes some extra effort.

Well life is a lot more practical here in the East. I never read safety note when I read article on the internet
For my case, I don't know how many power I got, just the oldest small battery charger in the planet with no indicator, I don't even know which lead is positive and which is negative, just see how they react if the bubble is on the wrong side, switch it the worst case isn't electrical shock but merely sparks when the two lead short circuited

This is A LOT simpler then you thought. The internet guide might be looks complicated, but it is actually peanut. Just use whatever charger available (I read somebody do that with computer power supply he has lying around), use as little water as possible (covering all blade surface), as much as sacrificial iron as possible, add a dash of washing soda, you can leave it and do your activities, you'll likely going to clean it off in less than half day, with little or no effort. You can pause and repeat the other day if necessary. I read on the internet it looks like they took days, this is not true for may case. You need to check after several hours, clean off the carbon, if you find red rust under the carbon repeat after you clean the remaining carbon. No need to do it too often.

I swear result is better compared to acid. I believe once you try it, you'll never look back into acid.

[Battara]

Nice piece! I think the blade is older, say, early 1800s. I agree that it originally had 2 baka-baka and that the scabbard is Maguindanao. The blade could be, but it could also be Sulu (they did a lot of trade). The hilt, there was something around the top, perhaps a band of metal. It also may have originally had metal ferrul too, but this is now covered by the later wrap.

A nice piece. Good luck with the "power etching"!

[tunggulametung]

Ok here is quick shot of before and after of last attempt. On macro there are some left over carbon in small cavities that need to be clean, but that can be done with oil easily later using softer small wire brush (need to find that for myself). Overall result is better in person/day light photo. This one take about two hours. Forget to mention, I use boiling water to start with. I guess you can also use quick and mild acid etch at this point so the blade didn't stays too long in acid such as in heavy cleaning.

Good luck.

[Battara]

Well, the etch for Moro swords is different and not as strong nor deep as it is for Indonesian pieces.

[Spunjer]

like tunggulametung said, you don't have to be specific. i used an ol' cheapo batt charger from sears, with 2Amps/8Amps switch, with it switched to 2 amps. then five 3/4" iron rebars and small gauge copper wires. i used carbonate soda (from walmart; brand name Arm and Hammer) for electrolyte and there you got it. just check up on it every 15-20 minute or so, depending how bad the rust is.

[mrwizard]

@Spunjer & Tunggulametung
Thanks for the pictures and detailed instructions.
I will definitely build a test-setup ( I have more than
enough rusty stuff lying around). If i will use it for the
moro kris i will decide later.

@Battara
Thanks for dating the kris. After looking at some picture
it may indeed be a sulu blade. I see no evidence of former metal applications on the hilt (nails, rifts, holes, etc.)
If there were any, the must have either been glued or the hilt must have been recarved after their removal.

I will keep you informed about the further progess.

Best Regards,
Thilo

[Sajen]

Originally Posted by mrwizard

I will keep you informed about the further progess.

Best Regards,
Thilo

Do you can post some results?

Regards,

Detlef

[mrwizard]

Originally Posted by Sajen

Do you can post some results?

Ooppss, sorry. The last year was a quite busy one and i'm just catching up on reading all the posts on this forum.

I built a test-setup large enough to contain a rusty crow-bar. As power-supply i used a computer power supply that is able to deliver 5A @12V. The counter electrode was a steel-band roughly the same length of the crow-bar and placed parallel to the crow-bar. The electrolyte used was sodium carbonate. And this is what happened: The power supply immediately switched off. I guess it detected a short. So i started pulling the setup out to see at what length of crow-bar could be cleaned with my setup (don't try this at home!). Turns out 40cm of crow-bar can be cleaned with this rather primitive setup. Putting in a high-power resistor that limits the current to 5A (2.4Ohms) would probably allow larger items at the cost of speed and isotropy.

However, i didn't follow that path because i didn't manage get the hilt off and i didn't want to stain the hilt with the rather nasty electrolitic solution. So i went to the classic approach with low concentration citric acid...

The results can be seen in the attached photos. The blade lamination that is not really visible on the photos shows a small edge around a uniform core.

[Sajen]

Good result!

[Indianajones]

are you going to give it an etch also? Although actually I do not see any 'activity' of lamination it might anyway improve the metal shine/appearance of the blade, and who knows . . . .
(am sure Sajen was about to ask the same?!? )

[mrwizard]

Hello Indianajones,

As i wrote i gave it very long etch during cleaning about a year ago. The lamination was easily visible back then... sadly i didn't make any photos.
Then i scrubbed it with steel wool and oiled it. Now the lamination is barely visible with the eye and very difficult to capture in photo.
But i will etch it again when i have time.

Originally Posted by Indianajones

are you going to give it an etch also? Although actually I do not see any 'activity' of lamination it might anyway improve the metal shine/appearance of the blade, and who knows . . . .
(am sure Sajen was about to ask the same?!? )