New Moro kris

[apolaki]

I have left the blade in a vertical bath of 5% vinegar for a couple days and tried to clean it a couple times by running water over it and scrubbing.

The dark smudge develops really fast after resubmerging in the vinegar. It develops thick again at both sides, and when I take it out of the bath to rinse it off with water and scrub it smells REALLY RANCID AND PUNGENT!!!! (Is it a toxin or hazardous to inhale)? My mind may be going overboard, but I wonder if it's arsneic or something? Any way, I was scrubbing it with a plastic brush very hard with citric dish soap thinking it will scrub the black smudge away, but it didnt seem to do much.

Then I realised that the black smudge actually fades away when the blade dries. The last photo shows what it looks like when it is almost completely dry. Is the rust not being removed or am I making some progress?

Thanks!

[Battara]

Uh..........maybe a little over etched. You may want to repolish and etch with a little distilled water, or don't leave the blade in that long.

[Sajen]

Originally Posted by Battara

Uh..........maybe a little over etched.

Hello Jose,
I think that we don't see an intended etch, it will be the result of the bath in 5% vinegar solution to loosen the rust.
That's what I said before, the blade need to get polished anyway after the bath. The blade wasn't corroded so much that the bath was required.

Regards,
Detlef

[Ian]

I agree Detlef. This blade needs some sand papering and polishing, then a final etch. The red area in the bottom picture is active oxidation that needs rubbing off also.
Ian

[Battara]

Oh.........I misunderstood.

[apolaki]

Hello all,

Is sand papering the only solution to this?

I thought vinegear will losen rust and it can just be scrubed with a hard brush and then dried with hair dryer and fonally oiled down.


But many are stating sand papering woth dofferent grades. What are some alternate solutions?

[apolaki]

Is the black smudge a result of zinc coating on the blade? I saw a video where vinegar turns zinc coated screws black. So did i essentially strip thhe zinc off the blade?

[Ian]

Originally Posted by apolaki

Hello all,

Is sand papering the only solution to this? ...

Manual removal with mild abrasive materials is standard operating procedures for this process. The same is true for Japanese swords, which use a slightly different abrasive method that (for me) is even more demanding and tedious.

... I thought vinegear will losen rust and it can just be scrubed with a hard brush and then dried with hair dryer and fonally oiled down. ...

Oh, if it were only that easy! There are no easy and quick short cuts I'm afraid. Not if you want a good result.

... But many are stating sand papering woth dofferent grades. What are some alternate solutions?

Manual removal, as has been suggested, is the simplest way to proceed. An alternative is to use mild abrasive blasting in a cabinet, BUT this takes experience (you need the right abrasive material, right flow rate, correct nozzle, etc.) and of course the necessary equipment including an abrasive blasting cabinet big enough to fit your work piece. The final result is a clean surface with a slightly matte finish. This will still need hand polishing and etching if you want an excellent result.

Some degree of manual work is necessary IMO if you want to achieve a good result that will be relatively maintenance free. Working the blade with your hands also gives a sense of what the original panday was trying to achieve, and an appreciation for the skill in forging these weapons. I always have a stronger sense of ownership when I have worked for several hours polishing and cleaning, and bringing an antique blade back to its earlier condition. Some people say they can feel the "spirit" of the blade when they are working on it. Can't say that I have, but I do have a greater affinity for a piece when there has been some sweat equity gone into making it look beautiful again.

Ian

[kai]

Hello Detlef,

The blade wasn't corroded so much that the bath was required.

I beg to differ: There are several deep cracks which surely were filled with rust. There is no way that a gentle polish of the surface would have removed these pockets of residual rust. Thus, for long-term preservation a limited acid soak was not a wrong strategy; with good planning, the process could have been shortened though.

Hardly any harm done in this case - we all have seen much worse restoration attempts, I believe!

Regards,
Kai

[kai]

Hello Apolaki,

Please try to answer those questions raised in post #18.

Regards,
Kai

[Sajen]

Originally Posted by kai

I beg to differ: There are several deep cracks which surely were filled with rust. There is no way that a gentle polish of the surface would have removed these pockets of residual rust. Thus, for long-term preservation a limited acid soak was not a wrong strategy; with good planning, the process could have been shortened though.

Hello Kai,
I have polished several moro blades with a much harder grade of corrosion without a bath in a vinegar or citric acid solution before, not one of this blades show until now new active corrosion.
But in general I agree, it can't hurt! I only want to state that it wasn't really required. And a more easy way would have been a direct polish.

Originally Posted by kai

any harm done in this case - we all have seen much worse restoration attempts, I believe!

For sure! So please don't push Apolaki to remove the hilt. Who get a small shock when he realize that he need to polish a blade (sorry Apolaki ) will have a great problem to fix the hilt later again proper. All my Moro kris blades I have restored by self never I have dismantled the hilt, the result is in many cases visible at this place, just search a little bit.
Yes, it's a little bit circuitous to polish a kris blade with attached hilt but for sure more easy as to dismantle a hilt and more to reattach it proper again IMVHO.

Regards,
Detlef

[Sajen]

By this pictures (taken from Gustav) you can see, how a kris hilt is constructed in many cases and I think Apolakis kris hilt as well. When the brass bands get broken when you want to dismantle the hilt you need to open the binding and you have a difficult restore object. It can be done but only for experienced persons.

Regards,
Detlef

[Battara]

Just a side note, Gustav's Moro hilt looks like it comes from Tawi-Tawi. Their hilts are made in this fashion.

Also Sajen is right - I've done a couple of Tawi-Tawi hilts before and it is a lot of work and time consuming.

[Ian]

Originally Posted by apolaki

... when I take it out of the bath to rinse it off with water and scrub it smells REALLY RANCID AND PUNGENT!!!! (Is it a toxin or hazardous to inhale)? My mind may be going overboard, but I wonder if it's arsneic or something? ...

Foul smelling liquids are often contaminated with bacteria and molds. Vinegar contains plenty of nutrients for microorganisms to grow in an aqueous medium. When you say it smells "rancid," I think you are referring to products resulting from microbial contaminants rather than a toxic gas being emitted from acid contacting the metal of the blade.

One possibility might be hydrogen sulfide ("rotten egg gas") if there is any sulfur in the metal. I've not heard of this being a problem with acid etching of steel/iron. Perhaps others have some more information on that possibility. Otherwise, I think your term "rancid" probably covers what is happening here.

Ian