Import BDNA-20785 Straight Flute Tap 10-32 Unf Bottoming Hss

Product Description

The IMPORT BDNA-20785 is a straight flute bottoming tap designed for cutting internal threads in through-holes and blind holes where full thread engagement close to the bottom is required. Manufactured from high-speed steel (HSS) with a gold oxide coating, this tap handles a 10-32 UNF thread profile with 4 flutes and a right-hand thread direction. The H3 thread limit designation indicates a tighter tolerance range suitable for standard UNF threading applications. Machinists, maintenance technicians, and tool and die professionals reach for bottoming taps when a plug or taper tap has already started the thread and the job requires threading as deep as possible into a blind hole.

This tap is suited for use in machine shops, maintenance and repair operations (MRO), and fabrication environments where 10-32 UNF threaded holes are required in steel, aluminum, and similar machinable materials. The bottoming chamfer — typically 1 to 2 thread leads — allows the tap to cut threads very close to the bottom of a blind hole, making it the final step in a standard three-tap sequence or a direct-use option in through-hole applications where full depth is needed.

Key Features

• 10-32 UNF thread form with 32 threads per inch for fine-pitch threading
• Bottoming chamfer geometry enables threading to near-full depth in blind holes
• 4-flute straight flute design provides chip clearance and thread accuracy in shorter-chipping materials
• High-speed steel construction offers heat and wear resistance for general-purpose tapping
• Gold oxide coating reduces friction and provides mild corrosion resistance during storage and use
• H3 thread limit for consistent fit within standard UNF tolerance classes
• Right-hand thread direction — standard for the vast majority of fastener applications

Compatibility

Designed as a direct-use straight flute bottoming tap for any application requiring a 10-32 UNF right-hand internal thread. Compatible with standard tap handles, T-handle wrenches, and machine tapping chucks sized for the tap shank diameter.

Installation Notes

Use of cutting fluid or tapping oil is strongly recommended to extend tap life and improve thread finish, especially in ferrous materials. Ensure the workpiece is securely fixtured before tapping to prevent tap breakage from misalignment. When tapping blind holes, periodically back the tap out to clear chips from the flutes. Broken tap removal in hardened workpieces is difficult — never force a tap that has stopped advancing.