Cleaning an old katana?

Delzhand · July 2014

So I've got an old katana that's really seen better days. Despite this, I really love the weight of it, and wouldn't mind if the blade shone a little brighter. I obviously don't need to retain a killing edge or need to slice tanks in half, but if there's anything I can do to improve the way this thing looks, I'd love to hear it. The blade is spotted with... well, I don't know. It's not foreign material, but I'm not sure how deep the stains go.

hsu · July 2014

That's rust.

Nocren · July 2014

If you wanna give it a shine, I suggest steel wool and a product called Nev-r-dull (or something to that effect). The product was what we used in boot camp to polish the recruit leaders' saber (they got a symbolic officer's sword/saber that they had to keep clean).

knitdan · July 2014

Is it like an antique, or just something from a mall ninja store?

I've heard that for old weapons, things like polishing and cleaning can actually decrease the resale value. Just something to keep in mind.

Delzhand · July 2014

It's an antique. I'm not actually worried about resale value - it's probably not worth much in its current state. I'm more interested in undoing some of the neglect I inflicted on it in my youth.

Pics of the other end if anyone is interested - it's got this neat thumb clasp that prevents it from coming out unintentionally:

knitdan · July 2014

That's pretty cool looking. I personally would leave the stains and discolorations because I think they add character, but Nocren's advice should work if you want to clean it up a bit.

Gonmun · July 2014

If you don't mind me asking Delzhand, how did you come to acquire it? The width of the blade and the styling of the handle with the one pin might suggest it's a Korean jingum rather then a katana. Slightly different methods used in making them but both have their own advantages and disadvantages in combat. As well, Korean jingums are rather rare to see overseas unless specially ordered through suppliers or schools as the actual method for making the original ones was nearly lost during the Japanese occupation of Korea. Based on the rust though I'd say your blade is either carbon or spring steel as stainless steel is normally less prone to it.

As far as cleaning, there are liquids like Pikal which is a metal polish used primarily for swords is one a lot of people seem to lean to. You can also try Metal Glo ( http://kultofathena.com/product.asp?item=UC136&afid=22347&tm=14&im=1 ) which seems to be highly recommended for general purpose polishing and has been said to get rid of some rust as well.

Choji oil you can also try for blade preservation to make sure it doesn't rust further. If that isn't readily available light mineral oil is a good alternative like liquid paraffin.

Delzhand · July 2014

I more or less inherited it from someone my mom knew. It's a type-95 Guntō (aluminum, not copper), but it's possible "katana" isn't accurate. I'm no expert.

Since it's in remarkably poor shape I might try steel wool. Even if I don't polish it just getting it down to a consistent surface and maybe fixing some of the worst defects on the edge I'll be happy. I'm considering cleaning up the scabbard and painting it black. I'm not holding onto this for historical or sentimental value, but of all the pointy objects in my house, it might be the only one worth a shit as an actual weapon (that's not true I could probably club someone with my Master Sword replica), and I wouldn't mind it looking like I didn't pull it out of an abandoned toolshed.

Hawkstone · July 2014

I would like to suggest one quick thing first...all of the above ideas are great for cleaning it up, but by all that is holy in case it is a legit antique take it to an antiques dealer before you do anything to it. It is entirely possible to completely devalue an item just by cleaning the patina of age from it. It is a matter of minutes that could be worth hundreds or even thousands of dollars if it turned out to be of value.

Xaquin · July 2014

Hawkstone wrote: »

I would like to suggest one quick thing first...all of the above ideas are great for cleaning it up, but by all that is holy in case it is a legit antique take it to an antiques dealer before you do anything to it. It is entirely possible to completely devalue an item just by cleaning the patina of age from it. It is a matter of minutes that could be worth hundreds or even thousands of dollars if it turned out to be of value.

PLEASE TAKE THIS ADVICE.

Delzhand · July 2014

Guys, this thing isn't a mystery sword. I know exactly what it is. These swords were mass produced just so officers would have something to carry. They're not traditionally forged. The market is flooded with fakes, and even real ones in good condition are only worth a few hundred. I'm not so hard up for cash that I'd get rid of it for even the good going price. I appreciate the sentiment, but the I don't think the standard wisdom applies here.

Nocren · July 2014

Yeah, about to say that thumb button thing is kinda the mark of a mass produced officer's katana. It might be worth something to a WW2 collector, but if he's intent on keeping it and actually using it for practice then give that thing a mirror sheen!

tinwhiskers · July 2014

Once you get it cleaned put some oil on it. Rem oil is the go to for guns, and I'd expect it to work well here too.

Psychotic One · July 2014

For Gurka Kukris they recommend using petrol to wipe down the blade to remove rust. If you need to scrub use something that would remove little to no material. Steel wool gently might work. Once you get it down to where you want it or can get it with out going crazy on the blade I'd recommend remmington oil to keep the blade from further weathering.

tarnok · July 2014

Just a quick look on ebay shows similar swords listed for over a thousand dollars. Even if it was a mass-produced piece of junk in its day it may have some value now, not just monetary value, but value as a historical object. Cleaning it could make it next to worthless.

bowen · July 2014

It could also have belonged to a specific person which would also make it more important.

Typhoid Manny · July 2014

This is one of those things that sounds like it should be simple but isn't necessarily. If you don't have access to certain tools and/or experience polishing steel, it isn't easy to take the patina off something without making it look worse than when you started. Depending on what particular kind of steel it's made of, steel wool will either be okay or it'll leave a million tiny marks on the surface of the steel itself which will then be a huge pain in the ass to get rid of. If you have access to a wire brush attachment for a bench grinder that'll make it easier, but if I were you I'd wipe it down with 3-in-1 to inhibit new rust from forming and leave the patina as-is. Making it look like it's brand new is a lost cause, you've already got some pitting which you won't be able to get rid of short of grinding down the surface a mm or two.

to summarize: you probably won't be able to make it look better than it does now, and you risk making it look way worse in the attempt. It'd be best to leave it alone but if your heart is set on cleaning it up, you need a bench grinder and a wire brush to put on it

Gabriel_Pitt · July 2014

Re: the quick look on ebay, is that completed auctions? That'd be the most relevant information.

Aside from what Manny said above, I'd recommend against cleaning it up too much because if that were mine, it'd take away a good amount of the sword's characters. Give the blade a gentle cleaning (see how a wipe down with petrol and a stiff clothes works), and light oiling to keep it from further corroding, and see where that leaves you.

Delzhand · July 2014

Well, the blade is harder than steel wool, because steel wool does nothing to it. On the other hand, the scabbard is starting to look very nice.

PedroAsani · July 2014

If you won't take it to an antique dealer, at least take it to a swordsmith. Expert advice prevents you goosing it up.

Typhoid Manny · July 2014

Delzhand wrote: »

Well, the blade is harder than steel wool, because steel wool does nothing to it. On the other hand, the scabbard is starting to look very nice.

You probably haven't even touched the actual blade yet. The patina is basically the same as the seasoning on a cast iron frying pan, and it serves the same purpose. If you manage to strip it off without messing up the steel itself, you'll then have to keep it coated in a thin layer of 3-in-1 or similar or else it'll just rust right back up. The pitting on the blade is also a Thing; even if you take the patina off and keep it from re-rusting, you'll have a very shiny blade except for spots where the rust ate in deeper. Rather than just looking like a cool old sword, it'll be a kinda-shiny sword that someone obviously tried to clean up

if you've got your heart set on cleaning the thing up, please please take it to a professional antique restorer. I've been doing metalworking for years and wouldn't try to do what you're trying to do, for fear of fucking up a cool antique like what you've got

edit: alternately, if it absolutely must be clean and you absolutely must do it yourself, practice first. Find some rusty old pieces of scrap steel and polish them up as shiny as you can. An old sword is not what you should be learning the ropes on

Psychotic One · July 2014

Be careful about removing the patina. It will make the blade much more vulnerable to rust. Patinas can be a good thing.

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