Simply treating your edged weapons with respect and care will easily keep them looking brand new for many years to come.
Sword Wielding
All edged weapons, battle ready or not, may injure, kill and/or become damaged if used improperly. Follow these simple do's and don'ts to safely enjoy your sword(s) for years to come.
Use common sense
Do not swing any edged weapon carelessly. Keep in mind that your sword, battle ready or not, is still a weapon that can injure or kill someone. Although we all have a "warrior" inside of us, we are not always on a battlefield. Make sure you are in an area where you can swing your weapon without hitting someone or something. Swords can also slip out of your hands. Selling your sword to pay for a lawsuit settlement is a big bummer. Be very careful and use common sense when handling your sword.
The Samurai respects his swords' edge and protects it at all costs
No matter how tough or strong the steel is in any sword, it will nick when struck against something equally hard. Do not bang your sword against another sword in theatrical-style duel. Do not bang your sword against any hard object to test its strength or the "sound" of the steel as it hits a hard object. In stage plays or in movies, theatrical swords with wide, thick edges are used. The edges are flat and often as much as 1/16 inches wide. Such theatrical swords are designed to take the flashy looking punishment of banging edges together. Your sword is not a theatrical sword. Your sword is a real weapon, designed so that they could fight in the manner that the originals were actually used. Since the cutting edges could easily be sharpened and were often used for slashing, parries were made with the flat of the blade (not the edges) or were simply avoided altogether. Real swords were never used for the theatrical style sword banging that movies or stage plays rely on to liven up action sequences.
Reasonable Use
Do not attempt to chop down a tree with your sword. Such an activity is guaranteed to damage your sword. Axes and machetes are well designed for this with the weight of the steel concentrated over the point of percussion. When you strike a firmly fixed object like a tree or a thick branch with a sword, a great deal of the blade projects past the object being cut, causing the blade to bend or torque. It should be pointed out that the Japanese, who believe in a lot of practice with the sword, used thick bamboo. The bamboo was resistant to a cut, but didn't have the rigidity of a tree, and so would not have damaged a valuable blade. For a Japanese warrior to cut in to a tree would have been unthinkable.
Sword Maintenance
What should you do first with your new sword? Proper sword care begins as soon as your new sword arrives.
Immediately After Receiving Your New Sword
# Factory direct swords will probably come to you with a light oil or a heavy coat of grease to protect the blades during transcontinental transport. To remove the grease you may use a solvent such as lacquer thinner or mineral spirits.
# Once you have finished this, apply your light coat of oil or a silicone spray. You can also wipe it with a silicone coated gun/reel cloth. In many respects, the gun/reel cloth is preferred as there is less tendency for dust to accumulate and trap oxygen to cause pitted areas in the blade.
# Since it is the natural propensity of steel to rust, you must properly care for your blades. Blades must be protected from moisture at all times. If surface rusting occurs, it can be removed with 600 grit or finer wet/dry sandpaper and some lightweight oil (i.e. gun oil, etc.). If you are consistently using the blade, the oil will work nicely. (Hint: wipe the blade with a soft cloth before using it, then apply a light coat of oil before storing the blade.) For display and decorative purposes, a carnuba-based wax (i.e. car wax) or a spray lacquer will work quite well.
How to Treat Wood or Leather
# Wooden handles may be treated with a light coating of lemon oil or tung oil to help prevent cracking.
# Leather scabbards and sheaths as well as leather covered handles should be treated with a good paste wax. The scabbard can also be treated with neatsfoot or mink oil for water proofing, although this is not recommended for gripping surfaces. Do not store your sword in its scabbard for long periods of time since the leather traps moisture which can produce rust spots on the blade.
Rust Prevention & Removal
Rust may be removed from your swords by either chemical or abrasive cleaning. Regardless of method, cleaning has its risks. Proceed with caution. Improper use or attention may damage your blades and/or their temper.
Rust Prevention
# All exposed steel will want to rust. Touching any exposed steel, such as your blade, with your bare hands will leave oils and salts that will eat their way into your blade and eventually leave pits. The best way to avoid this is not to touch the blade and to wipe off the blade if it is touched. It is also a good idea to inspect your swords at least annually to check for new rusty areas and to use fine steel wool or Nev-R-Dull on them. Don't forget to change the oil, too.
Rust Removal
I know of two methods of cleaning the rust off of steel -- chemicals and abrasion. I'll try to give several examples of each, in order of weakest method to harshest. Always start with something weak -- it's easier to take rust off than to put steel back on. BTW, we haven't tried most of these, and use caution with any chemicals.
Chemical Cleaning
# You can use a Sword Cleaning Kit or Nev-R-Dull for a mild chemical cleaner. It removes light surface rust and dirt, and is safe to use. It is available at your local automotive store and I believe it is cotton with a penetrating oil. It is oily feeling and leaves a slight residue on anything it is rubbed against. Rub the rusty area with a small piece and then wipe it off. Great for removing rust caused by light handling or humidity. Always test it on a small area if in doubt. Not recommended for blued blades (haven't tried it). I have also heard of a product called Flitz Metal Polish . ( recommended by the manufacturer in Toledo , Spain )
# Acids. Yup, you read that right, just be careful and go slow. Start with some mild household acids -- try lemon juice first. It may take a few days, but check it periodically. Next would be vinegar (mild ascetic acid), and then Worcestershire sauce. My preference is a mild solution of carbonic and phosphonic acids that goes by the trade name of Diet Pepsi (takes about 3 days, followed by some steel wool and nev-r-dull). If those don't work, A 1 molar solution of a medium-strong acid, such as muriatic or phosphonic acid, will slowly eat away the rust. Check your pool supply store for these. They may take a few hours, but check them regularly! They will eventually eat into the blade if left too long. Strong HCl will eat the rust off in seconds (I use it to clean rusty tools at work), but I do not recommend this method for use on a sword. A strong acid will leave microscopic etching, which will give a dull, leaden look to the blade.
# Electrolysis is the process of breaking apart the rust molecules into iron and oxygen, then binding the oxygen to a more active metal. One method is to immerse the blade (remove the handle first) in a slightly basic solution (caustic soda or lye) while it is surrounded with metallic zinc. The reaction will eat the rust and produce zinc oxide. It is important that a basic solution is used to prevent further rusting of the steel, and make sure that the surface to be oxidized is a more active metal than iron. Check a college chemistry book when in doubt. Do not use aluminum foil, because it is more stable than iron and will cause the iron to rust away. The process takes a few hours, so check it regularly. The process can be speeded up by connecting a car battery to the apparatus as such: negative to iron, positive to zinc. I have been told that electrolysis can leave a blade looking 'cooked,' and that it destroys the original temper of the blade.
I've been told that exposure to high heat will remove rust, but this will discolor the blade and destroy the temper.
Abrasive Cleaning
# Oil and steel wool is the most often prescribed way to remove light surface rust. You know how to use it already, so there is no need to say more. Scotch-brite pads and olive oil make a good alternative, for the more kitchen inclined collectors.
# Rubbing the steel with a piece of copper will remove rust as well. Since copper is softer than iron, it won't scratch the surface, either. I have never tried it before, but I don't think it would take off any patina.
# A soft wire brush works the same way, and may be useful for a sword that is already heavily pitted or scaled with rust. The bristles shouldn't put enough pressure on the steel to scratch it, so it should be ok. I have seen wire wheels for drills, and they might work as well. Test it on a small area first before attacking the whole blade.
# Polishing stones are used in knife making, and will give a mirror finish to the blade. Remember, though, that this may actually detract from the value of the sword. Also remember this -- it takes a 5-year apprenticeship to learn to make a Japanese sword, and a 10-year apprenticeship to learn to polish one. 'Nuff said.
I assume that abrasive cleaning compounds might work, but that they would leave scratches on the blade. Test a few out if you want to try this method.
Very fine grit sandpaper will leave scratches, but it is good for a hard assault on scaled rust. Be careful to only be rubbing the rust, though.
Sword Storage & Feeding
Just because you don't own a museum-quality display case doesn't mean that your swords are at the mercy of the elements. Lacking a museum-quality temperature and humidity controlled lockable display case does not mean that your collection can't be displayed safely. The average collection is not damaged by being hung on a wall with steel hooks (not aluminum) or on wooden display racks. In high humidity areas, though, it is best to keep your collection stored in a sealed case with enough desiccants to keep the humidity beneath about 30% to hinder rust.
It is also very important to KEEP SWORDS OUT OF THE HANDS OF CHILDREN. Children will destroy a sword in a fraction of the time it takes rust. Also keep swords out of reach of people who want to clash blades like in the movies or cut down trees with them.
Long Term Storage
If you do not wish to display your swords, the most important ways to protect your collection are to protect it from rust, skin contact, and theft. A gun safe will protect it from all of these. If that route is unavailable, however, we recommend either using a gun sock or making a sword bag. In either case, we recommend placing a few packages of desiccant in with the sword to keep humidity down.
Blade Coatings
# Your blade, being steel, will appreciate regular coats of a clear, non-organic, oil. This prevents moisture from reaching the blade, as well as giving a nasty sliming to anyone who touches it. Collectors of Japanese swords recommend choji, which is mineral oil with a small amount of clove oil for scent. We also recommend a light oil such as sewing machine oil or gun oil. We've heard of using 10W30, but can't comment as its usefulness. Oil should be changed regularly by wiping the blade with a soft cloth until dry, then applying more.
# Cosmoline, a Vaseline like substance, and grease were often used in the past, but now are getting looked down upon. If you have an old blade covered in it, rest assured that it will still be protected, but there may be microscopic pits in the blade that would make a collector of Japanese swords cringe. The stuff is quite ugly as well, but at least it keeps hands off…
# Another option is to apply a wax coating. We've heard of using carnauba wax (like on your car), but cannot comment to its long term effects. You might want to check your local automotive store/department to ask about which waxes are best on steel.
# The final viable option is a clear varnish. Del Tin, a respected maker of medieval replica swords, puts a coat of varnish on their sword blades. We recommend making sure there are no fingerprints or specks of dust on the blade first, or else they will eat into the blade from beneath the coating.