How should I store and maintain a hand forged tachi?

Long-term storage of a hand forged tachi requires controlling two primary threats: moisture and skin oils. After handling, wipe the blade with a clean, lint-free cloth to remove fingerprints, then apply a thin, even coat of traditional choji oil (or a quality mineral oil) using a soft cloth or dedicated uchiko application. This preserves the steel's surface and prevents oxidation. Store the tachi horizontally on a dedicated sword stand or in its saya in a climate-controlled environment - avoid basements or spaces with fluctuating humidity. If storing long-term in the saya, leave a very slight gap at the koiguchi (saya mouth) to allow air circulation and prevent moisture buildup inside the saya. Inspect the blade every one to two months, re-oiling as needed. Lacquered saya should be wiped with a dry cloth only; avoid oil on lacquer surfaces as it can cloud the finish over time.

What is clay tempering, and which tachi pieces in this collection feature it?

Clay tempering is a heat-treatment technique in which a mixture of clay is applied along the spine and flat of the blade before the quench, leaving only the edge area exposed. During the rapid quench in water or oil, the uncoated edge cools faster and achieves greater hardness, while the clay-insulated spine cools more slowly, remaining tougher and more flexible. The result is a blade with a visible hamon - the wavy or straight line separating the harder edge from the softer body - which is one of the most prized visual features in Japanese sword collecting. The clay tempered 1095 carbon steel tachi with teal ito wrap in this collection explicitly undergoes this process, producing a blade with both authentic structural character and strong display appeal.

How should I store and maintain a lacquered saya tachi?

Lacquered saya are sensitive to humidity fluctuations, which can cause cracking or lifting of the lacquer surface over time. Store your tachi horizontally on a display stand in a climate-controlled room, away from direct sunlight and heating vents. For the blade, apply a thin coat of choji oil or neutral mineral oil every few months using a soft cloth to prevent oxidation, especially if you handle the blade directly (skin oils accelerate surface rust). Never leave the blade seated in the saya for extended periods without occasional airing, as trapped moisture inside the wooden scabbard can mark the steel. White gloves are recommended for any handling session.

How should I store and maintain a display tachi long-term?

Proper long-term care for a display tachi focuses on three priorities: controlling humidity, preventing surface oxidation, and protecting the saya. For the blade, apply a thin coat of choji oil or a neutral mineral oil every two to three months using a soft, lint-free cloth - this creates a protective barrier against moisture and airborne contaminants. Store the tachi horizontally on a dedicated sword stand in a climate-controlled environment, ideally between 40-60% relative humidity. Avoid placing it in direct sunlight or near heating vents, as temperature fluctuations can warp the wooden saya and cause the lacquer or finish to crack. When handling, use cotton gloves or hold the saya rather than the blade - skin oils accelerate surface oxidation on high-carbon steel. For long-term storage, wrapping the saya in a silk or cotton sword bag adds a further layer of protection without trapping moisture.

How should I maintain a 1060 carbon steel tachi on display?

Updated Mar 2026

Carbon steel requires more active care than stainless alternatives, but the routine is straightforward. Every two to three months - or whenever you handle the blade directly - apply a thin, even coat of choji oil (traditional camellia oil blend) along the entire blade surface using a soft cotton cloth or dedicated nuguigami paper. This creates a micro-thin barrier against oxidation. Store the tachi in a stable environment: target indoor humidity between 40-60% RH and keep the piece away from exterior walls, air conditioning vents, or direct sunlight, all of which cause temperature and humidity fluctuations that accelerate surface oxidation. If the saya is lacquered wood, avoid sealing it in an airtight case - wood needs to breathe. Periodically inspect the blade for any rust spots; early-stage surface rust can typically be addressed with a light application of oil and gentle removal with a clean cloth.