Handmade Octagonal Wa-Handle 115mm - Solid Bubinga Wood (Mono-Construction)

Proportioned specifically for compact cutlery, nimble paring work, and off-the-board peeling, this 115mm octagonal (Hakkaku) Japanese knife handle is carved from a single, unbroken block of select African Bubinga wood. By utilizing a seamless mono-construction design with no composite ferrule joint, this handle preserves the continuous flow of natural grain from the blade collar through to the butt, ensuring structural strength, clean lines, and an uninterrupted tactile feel.

Often dubbed "African Rosewood" for its rich burgundy hues and fine, interlocking grain, Bubinga (Guibourtia demeusei) is naturally dense and resinous. It resists ambient kitchen humidity, juices, and warping while providing just enough counterweight mass to anchor small, featherweight blades comfortably in the palm without making them handle-heavy.

Engineered specifically for custom petty builds, fruit knives, and fine restoration work, the collar is pre-machined with a narrow 9mm x 1.75mm tang entry slot backed by an internal secondary relief chamber. This opening is precisely scaled for thin-stock forged petty tangs and laser-ground utility blades, while the relief reservoir allows displaced epoxy or hot-melt adhesive to expand freely without inducing hydraulic pressure splits in the dense natural timber.

Key Features

• Seamless Mono-Construction: Carved entirely from a single solid block of dense Bubinga wood. Completely eliminates glue joints, material seam lines, and unequal expansion rates between wood and horn.

• Continuous Natural Grain Figure: Unbroken grain runs the full 115mm length of the handle, highlighting Bubinga’s characteristic crimson-to-espresso undertones and subtle chatoyant luster.

• Scaled 115mm Petty & Paring Profile: Proportioned specifically to avoid throwing off the balance of short blades. Delivers optimal fingertip dexterity and palm clearance for 75mm–120mm Pettys, paring knives, and compact fruit knives.

• Natural Moisture & Fluid Resistance: Naturally dense and oily, Bubinga resists kitchen moisture and staining, maintaining a smooth, tactile surface during delicate, high-moisture prep work.

• Ergonomic Octagonal (Hakkaku) Geometry: Symmetrical eight-faceted geometry naturally seats into the joints of the fingers, providing crisp edge-angle feedback and positive traction during intricate peeling, coring, and trimming.

• Precision 9mm x 1.75mm Tang Entry: Tailored specifically for delicate, thin-tang petty and paring profiles, avoiding loose fits or excessive gap filler.

• Internal Relief Chamber: Bored with a secondary expansion cavity behind the primary entry slot to safely catch displaced adhesive during installation, preventing hydraulic pressure splits inside the solid timber.

Technical Specifications

Installation & Fitting Guidelines

• Tang Sizing & Rasp Adjustment: The 9mm x 1.75mm slot is designed for slender petty tangs. Because dense Bubinga wood has minimal elasticity, never force an oversized tang into the mortise. If your blade's tang spine sits slightly thicker than 1.75mm, use a narrow diamond needle file to ease the wood entry until achieving a snug friction fit.

• Relief Channel Dynamics: When inserting the tang with hot-melt glue or epoxy, the integrated internal relief cavity allows displaced bonding agent to expand safely, eliminating internal hydraulic back-pressure that could otherwise stress the wood grain.

• Adhesive Selection:

  • Traditional / Reversible: Jeweler’s hot-melt glue or wood glue blended with fine matching wood dust allows for clean, heat-reversible removal in the future.

  • Permanent Installation: Marine-grade two-part epoxy (e.g., G/flex 650) creates an impervious, 100% waterproof seal against internal moisture intrusion.

• Solid Hardwood Care: Solid timber should never be soaked in standing water or run through a dishwasher. Maintain moisture resistance and highlight the deep burgundy tones of the grain by periodically conditioning the handle with pure camellia (tsubaki) oil, food-safe mineral oil, or board wax.