Guhring 9039100222250 Spiral Flute Tap 7/8-9 Unc Tin

Product Description

The GUHRING 9039100222250 is a spiral flute tap designed for blind hole threading in demanding materials including aerospace alloys and stainless steel. It cuts a 7/8-9 UNC right-hand thread to a 2B class of fit using a modified bottoming chamfer, making it suitable for threading holes that require full thread depth close to the bottom. The tap is manufactured from powdered metal for increased wear resistance and is coated with TiN (titanium nitride) to reduce friction and extend tool life. With a 40-degree helix angle and fast flute style, it efficiently evacuates chips upward out of the hole during the cut. Licensed HVAC techs and machinists in aerospace and industrial fabrication shops are the primary users of this tool.

This tap is applied in blind hole threading operations on aerospace alloys and stainless steel where a UNC 7/8-9 thread form is required. The modified bottoming chamfer allows threading closer to the bottom of a blind hole than a standard plug or taper tap. The 4-flute, right-hand spiral design with a 40-degree helix angle provides positive chip ejection in these tougher materials, reducing the risk of chip packing and tap breakage. It is suited for use in machining centers and manual tapping operations where consistent 2B thread fit is required.

Key Features

• 7/8-9 UNC right-hand thread, 2B class of fit with H6/H7 thread limit tolerance
• Modified bottoming chamfer for threading close to the bottom of blind holes
• Powdered metal construction for superior wear resistance in hard and abrasive materials
• TiN coating reduces friction and extends tool life in aerospace alloys and stainless steel
• 40-degree helix angle with fast flute style promotes upward chip evacuation
• 4-flute, right-hand flute direction for balanced cutting action

Compatibility

Designed for blind hole threading applications in aerospace alloys and stainless steel. Suitable for use in machining centers and manual tapping setups requiring a 7/8-9 UNC, 2B class of fit thread with H6 or H7 thread limit tolerance.

Installation Notes

This tap should be installed and operated by qualified machinists or tool-and-die professionals familiar with tapping speeds, feeds, and cutting fluid requirements for stainless steel and aerospace alloys. Always ensure the workpiece is securely clamped and the spindle is properly aligned before beginning the tapping cycle. Use an appropriate cutting fluid rated for the workpiece material to prevent galling and premature tool wear. Do not reverse direction before the tap has fully entered the cut, and inspect the tap for wear regularly when working with abrasive or work-hardening materials.