Japanese Sword Care — The Complete Collector's Guide to Handling, Maintenance, and Long-Term Preservation

A genuine nihonto — a blade forged from tamahagane steel, polished by a certified tōgishi over weeks of careful work — is one of the most precisely finished metal surfaces in existence. Genuine Japanese swords are typically polished using more than ten different types of grinding and polishing stones, creating a surface of extraordinary smoothness and sensitivity. That surface requires specific care. Not complicated care — but specific care, applied consistently. This guide covers everything: how to handle your blade safely, how to perform full maintenance, and how to preserve a nihonto for the long term — whether it has been with you for a year or is accompanying you for the next fifty.

Part One — Handling Your Sword Correctly

Every interaction with your sword is a maintenance moment. The way you store it, carry it, draw it, and sheath it determines whether the blade, the scabbard, and the fittings remain in the condition they deserve. The following principles apply whether your sword is a Kamakura-period antique or a recently forged modern blade — and whether it is in shirasaya or full koshirae.

Storage and transport

Whether your sword is in shirasaya or koshirae, it should always be stored in a katana bukuro — a sword bag. When placing the sword in the bag, insert it kojiri (scabbard end) first. This is not ceremony; it is practical safety. If the blade slips from the saya unexpectedly, inserting the kojiri first means the sword exits the bag handle-first rather than blade-first.

Store your sword in a katana bukuro — always kojiri first, never blade first

When carrying a sword, hold it in your right hand with the tsuka facing upwards and the tip pointing downward. This prevents the blade from sliding out of the saya under its own weight. The same orientation applies when drawing the sword from its bag.

Always carry the sword in your right hand with the tsuka upwards and the tip pointing toward the ground

Before drawing — a moment of respect

Before drawing your sword, remove any jewellery, watches, rings, or bracelets. Metal against the blade surface can cause scratches that a certified polisher will need to address. Bow to the sword before drawing — this is not empty formality. It creates a moment of focused attention that prevents the rushed, careless handling that causes damage.

A bow before drawing — the pause that focused attention requires

Drawing the sword

Grip the saya with your left hand from underneath, with your fingers supporting the mune (spine side) and the cutting edge facing upwards. Your right hand grips the tsuka from above, fingers on the ha (cutting-edge) side. Gently ease the sword out of the saya — never force it.

Left hand supports the saya from underneath; right hand draws the tsuka gently from above

The first action is koiguchi wo kiru — draw the sword just until the habaki (blade collar) becomes visible. Pause there. Confirm your grip, confirm the blade's orientation, and then continue drawing slowly, allowing the back of the blade to follow the curve of the saya interior without rattling. Never draw or carry the sword with the cutting edge facing down or sideways.

Sheathing the sword

Sheathing uses the same grip as drawing. Bring the tip of the blade to the koiguchi with the cutting edge facing upwards and the back of the blade leading. Allow the mune to follow the inner curve of the saya as the blade slides in. Once the blade is fully seated, press the habaki firmly into the koiguchi to lock it in place.

Sheathe slowly and deliberately — the back of the blade leads, following the saya's curve

Part Two — Complete Blade Maintenance

The purpose of blade maintenance is straightforward: remove old oil and replace it entirely with fresh oil, covering every part of the blade's surface. Oil that has degraded or become contaminated is worse than no oil — it can trap moisture against the steel and accelerate the corrosion it is supposed to prevent.

Because a genuine nihonto's polished surface is sensitive to any particles on maintenance tools, inspect every piece of nuguigami and your abura-nuguishi carefully before use. A single piece of grit on a maintenance cloth can scratch a surface that took a polisher weeks to create.

How often to perform maintenance

The complete maintenance sequence — step by step

Lay the sword horizontally on a clean surface. Use the mekugi-nuki (peg remover) to tap the bamboo mekugi out of its hole. With the mekugi removed, the tsuka can be released from the nakago.

Use the mekugi-nuki to push the bamboo peg (mekugi) out before removing the tsuka

Draw the blade using the technique described in Part One. If the blade is stuck in the saya, grip the koiguchi firmly and apply pressure to loosen it.

Draw the blade slowly and carefully — do not rattle it inside the saya

Hold the tsuka with your left hand on the mune side, blade angled slightly upward. Use your right fist to tap your left wrist lightly — the nakago will gradually work loose inside the tsuka. Repeat until the nakago can be gripped and withdrawn. Begin gently — short tanged blades such as tantō can spring out entirely if struck too hard.

Right fist taps left wrist lightly — the nakago loosens gradually. Start gently.

If the nakago is firmly stuck, a wooden mallet (kizuchi) can be used — cover the tsuka with cloth first

For swords in full koshirae, the sequence after removing the tsuka is: seppa (washers) → tsuba → habaki. If the habaki is stuck, lightly tap the back of the habaki through a cloth with the kizuchi.

A light tap at the nakago end helps loosen a stuck habaki — protect the habaki with cloth

Take the first sheet of nuguigami and fold it in half toward the cutting edge with the blade's spine side up. Grip the paper-covered blade gently from above — thumb and forefinger either side of the cutting section. Wipe from habaki toward the kissaki in one smooth, unhurried motion. At the kissaki, lift the paper away rather than turning it around — never drag nuguigami back across the kissaki tip. Keep this first sheet clearly separate from the second sheet used in Step 6.

First nuguigami sheet — preliminary cleaning to remove old oil and surface particles

At the kissaki, lift the paper away — never drag nuguigami back across the tip

Pat the uchiko ball lightly against the blade surface — starting from the habaki end, working toward the kissaki on the sashi-omote (front face). Then turn the blade over and pat from kissaki toward the habaki on the sashi-ura (back face). The powder should coat the surface in a thin, even layer. Do not press — the uchiko works through contact, not pressure.

Uchiko applied lightly from habaki to kissaki on the front face, then kissaki to habaki on the back

Using the second, clean sheet of nuguigami, wipe the blade in the same manner as Step 4. This removes the uchiko together with the final residue it has lifted from the surface. If the blade does not clean completely after one pass, reapply uchiko and repeat Steps 5 and 6. The first sheet (from Step 4) and this second sheet must never be swapped. Label or mark them to keep them distinct.

Second nuguigami sheet — final cleaning to remove uchiko and all surface residue

Fold a piece of abura-nuguishi (oiling paper or clean flannel) to approximately 3cm × 6cm. Apply a small amount of chōji-yu — enough to dampen the paper but not saturate it. The oil should spread in a thin, even film; excess oil risks contaminating the saya and koshirae when reassembled.

A small amount of chōji-yu on the abura-nuguishi — enough to dampen, not saturate

Draw the blade from the saya and apply oil using the same wiping motion as the cleaning steps — from habaki to kissaki on the front face, kissaki to habaki on the back. Repeat to ensure complete coverage. The film should be visible as a slight sheen, not as pooling or running oil.

Oil applied in the same motion as cleaning — thin, even coverage across the entire surface

Replace the habaki. Temporarily sheath the blade while you prepare the tsuka. Hold the nakago upright in your right hand and lower the tsuka onto it with your left hand. Tap the end of the tsuka lightly with the palm of your right hand to seat the nakago fully. Replace the mekugi and confirm it is seated — the nakago must not move inside the tsuka.

Lower the tsuka onto the nakago, then tap the end lightly to seat it fully

Replace the mekugi — confirm the nakago seats firmly with no movement

Sheath the blade cutting edge upward, allowing the mune to follow the saya's curve. Push the habaki firmly into the koiguchi to lock the blade.

Return the blade to the saya cutting-edge up — the mune leads, following the saya's curve

Part Three — Long-Term Preservation

The maintenance process in Part Two addresses the blade's surface. Long-term preservation addresses the environment in which the blade lives — the conditions that determine whether rust, contamination, and physical damage accumulate between maintenance sessions. Four principles govern this.

• Store in shirasaya for long-term preservation. Koshirae — particularly older koshirae — can accumulate rust and contamination on the interior of the saya over decades, which then transfers directly to the blade. Magnolia wood (ho-no-ki) is the traditional material for shirasaya precisely because it is soft, non-abrasive, and regulates moisture naturally. If you think of koshirae as formal wear for the blade, shirasaya is its resting state. Any sword that will be in storage for more than a few months should be in shirasaya if at all possible.
  

  Shirasaya — the blade's resting scabbard. Magnolia wood, fitted precisely to the individual blade. Note the sayagaki inscription by a scholar appraiser, which is one of the features that makes shirasaya significant beyond simple storage.

• Store horizontally. A blade stored vertically or at an angle causes oil to migrate toward the lowest point — pooling at the kissaki or collecting in one area of the saya interior. This uneven distribution leaves parts of the blade unprotected and can cause accelerated corrosion at the pool point. A horizontal sword rack or a paulownia wood box in which the sword lies flat are the correct storage solutions.
  

  Horizontal storage on a proper sword rack — the only correct orientation for long-term preservation

• Control humidity. High humidity accelerates rust. Low humidity protects the steel but can damage wooden components — old koshirae with lacquered scabbards and decorated fittings may crack or warp in excessively dry conditions. The ideal environment balances low humidity for the steel against moderate humidity for the wood and lacquer. Avoid basements, bathrooms, and any space where humidity fluctuates significantly.
  

  The kissaki — the tip — is among the most vulnerable areas of the blade to rust and physical damage. Correct storage and consistent oiling are both essential.

• Never attempt rust removal yourself. If rust appears on the blade surface, do not attempt to remove it with a spatula, sandpaper, or any abrasive material. Amateur rust removal almost invariably causes further and deeper damage to the polished surface — often far more costly to correct than the original rust. Take the blade to a qualified tōgishi (certified sword polisher) immediately. The cost of professional rust removal is a fraction of the cost of repolishing a blade that has been scratched by inexperienced repair attempts.

In Closing — Care Is Relationship

The maintenance of a Japanese sword is not a chore. It is the ongoing relationship between the collector and the blade — the moments of direct attention in which you learn what the sword looks like, how its surface responds to light, what the ji and hamon reveal at different angles. A collector who maintains their own blade regularly develops an eye for it that no amount of reading can substitute for.

The polisher who spent weeks creating the surface you are maintaining did so with the understanding that the surface would be cared for. The smith who forged the steel worked with the understanding that the blade would be preserved. Every session of correct maintenance honours both — and extends the blade's life by another increment toward the centuries it was built to last.

Handle it carefully. Maintain it consistently. Store it correctly. These three things are all a genuine nihonto requires — and they are within the reach of any collector willing to give the blade the attention it deserves.