Jacobs JCM3639P Drill Chuck Key K0M 1/8 in Pilot

Product Description

The JACOBS JCM3639P is a drill chuck key designed to tighten and loosen drill chucks in workshop and field drilling applications. Designated as key number K0M, it features a 1/8 inch (0.1200 inch decimal, 3.17 mm) pilot diameter that seats securely into the chuck pilot hole to prevent slippage during chuck adjustment. This key is compatible with 0 Series Stainless chucks. Machinists, maintenance technicians, and trade professionals who work with JACOBS chucks will find this a direct-fit replacement or spare for standard bench drill presses and handheld drilling equipment.

The JCM3639P is suited for use wherever a K0M-style chuck key is specified. It applies to benchtop drill presses, magnetic-base drills, and similar equipment fitted with a compatible JACOBS 0 Series Stainless chuck. The 1/8 inch pilot diameter is a precise fit for the matching chuck pilot bore, ensuring full gear engagement and consistent torque transfer when setting bit clamping force. This key is a standard single-piece item sold individually.

Key Features

• Key number K0M with a 1/8 inch pilot diameter for precise chuck engagement
• Decimal pilot diameter of 0.1200 inches (3.17 mm) for consistent seating
• Compatible with JACOBS 0 Series Stainless drill chucks
• Sold as a single unit - suitable as a replacement or on-hand spare
• UNSPSC Code 27112800 for procurement and catalog matching

Compatibility

Designed for use with JACOBS 0 Series Stainless drill chucks requiring a K0M key with a 1/8 inch pilot diameter.

Installation Notes

Chuck key service is typically performed by machinists or maintenance technicians working on drilling equipment. Before changing or adjusting chuck tooling, ensure the drill press or power tool is fully powered down and unplugged or locked out per OSHA lockout/tagout procedures. Insert the pilot pin fully into the chuck pilot hole before applying rotational force to avoid gear skipping or pilot damage. Inspect the key periodically for worn gear teeth, which can strip the chuck ring and make future adjustment difficult.