Value Collection MSC-04480216 1/4-20 Unc Bottoming Tap Hss

Product Description

The VALUE COLLECTION MSC-04480216 is a straight flute bottoming tap designed for cutting 1/4-20 UNC internal threads in through-holes and blind holes where threads must extend close to the bottom. Ground from high-speed steel with a bright, uncoated finish, this tap produces clean right-hand threads to a 2B class of fit with an H5 thread limit. The bottoming chamfer — typically 1 to 2 threads — allows the tap to engage the workpiece at the base of a blind hole, making it a common third-tap choice in a plug-then-bottom sequence. Machinists and maintenance technicians use this tap in hand-tapping operations and low-speed machine setups.

This tap is suited for general metalworking applications in job shops, maintenance facilities, and production environments. It threads stock materials including mild steel, aluminum, brass, and plastics where a 1/4-20 UNC thread form is required. With a thread length of 1 inch and an overall length of 2.5 inches, it fits standard tap handles and collet-style holders used in drill press and CNC tapping applications at appropriate reduced speeds.

Key Features

• Bottoming chamfer allows threading to the base of blind holes
• 4 straight flutes for efficient chip evacuation in through-hole and shallow blind-hole applications
• High-speed steel construction provides durability across a range of common workpiece materials
• Bright, uncoated finish suitable for use with cutting fluid in standard tapping operations
• 2B class of fit with H5 thread limit meets standard tolerance requirements for most general-purpose assemblies
• Right-hand thread direction compatible with conventional tap handles and tapping heads

Compatibility

Designed as a standard 1/4-20 UNC bottoming tap compatible with tap handles and tapping attachments that accept straight-shank taps of this size and overall length.

Installation Notes

This tap is installed by a machinist or maintenance technician using a T-handle tap wrench or appropriate machine tapping attachment. Always use a cutting fluid or tapping compound suited to the workpiece material to reduce heat and extend tool life. In a blind-hole sequence, use a taper or plug tap first to establish the thread, then follow with this bottoming tap to extend threads to the required depth. Do not force the tap against the bottom of a blind hole, as this may cause tap breakage.