Collis Tool 78917 Tapping Adapter 3/8 Inch Through Coolant

Product Description

The COLLIS TOOL 78917 is a tapping adapter designed for use with 3/8 inch taps in quick-change tooling systems. It accepts a tap with a 0.381-inch shank diameter and a 0.286-inch square size, providing a secure, positive drive connection. The adapter supports through-coolant delivery, directing coolant fluid directly through the tool to the cutting zone for improved chip evacuation and tap life. It is sized as a Number 1 adapter and is installed by machinists and toolroom technicians on CNC machining centers, tapping machines, and manual turret lathes.

This adapter is suited for production tapping applications in job shops, manufacturing facilities, and toolrooms where quick-change tap holders are used. The through-coolant feature makes it well suited for deeper tapping operations or materials that generate heat and require active cooling at the cutting edge. The compact projection of 0.28 inches and a tap depth capacity of 1.05 inches allow it to fit into tight setups without sacrificing reach. A flange diameter of 1.18 inches provides the seating surface for secure engagement with compatible quick-change toolholding systems.

Key Features

• Accepts 3/8 inch tap with 0.381-inch shank diameter and 0.286-inch square size
• Through-coolant design channels coolant directly to the tap cutting zone
• Quick-change compatible for fast tap swaps without removing the holder body
• Tap depth capacity of 1.05 inches for adequate reach in standard tapping applications
• Flange diameter of 1.18 inches for stable seating and drive engagement
• Compact 0.28-inch projection minimizes interference in close-clearance setups

Compatibility

Designed as a Number 1 size quick-change tapping adapter for use with 3/8 inch taps in compatible quick-change tap holder systems.

Installation Notes

Installation is performed by machinists or toolroom technicians. Always de-energize and lock out the machine before changing tooling. Verify that the tap shank diameter and square size match the adapter specifications before seating the tap. Confirm coolant passages are clear and free of obstructions before running through-coolant at operating pressure.