Jacobs 30427DN Morse Taper Reducing Sleeve MT1 MT4

Product Description

The JACOBS 30427DN is a standard Morse taper reducing sleeve designed to adapt tooling with an MT1 inside taper to a spindle or socket with an MT4 outside taper. The body is soft steel with a hardened tang, providing durability at the drive point while allowing straightforward removal with a drift. Overall length is 4.88 inches with a 0.25-inch projection. This sleeve is used by machinists, tool-and-die workers, and maintenance technicians to mount smaller-shank tooling in larger machine spindles without adapter loss or chatter.

Morse taper reducing sleeves like the 30427DN are commonly installed in drill presses, lathes, milling machines, and boring machines where the spindle taper is larger than the tool shank taper. The MT1-to-MT4 configuration is a typical requirement when running smaller drills, reamers, or center points in heavy-duty spindles. This sleeve suits both production and job-shop environments where mixed tooling sizes are routine.

Key Features

• MT1 inside taper accepts standard MT1-shank tooling
• MT4 outside taper seats directly in MT4 spindles or sockets
• Soft body with hardened tang for reliable drift removal
• 0.25-inch projection for consistent tool positioning
• 4.88-inch overall length for proper spindle engagement depth

Compatibility

Designed as an OEM-style reducing sleeve for machine spindles requiring an MT4 outside taper with MT1 inside taper tooling fitment.

Installation Notes

Installation is performed by machinists or maintenance technicians. Power down and lock out the machine spindle before seating or removing the sleeve. Clean both the sleeve and spindle socket thoroughly before insertion to ensure full taper contact and prevent fretting. Use a proper drift bar and soft mallet to eject the sleeve - never strike the tooling directly.