03B163 - Walter 1"-8 NC HSS Bottoming Tap for Blind Holes

Precision Threading with Walter High-Speed Steel Technology

The Walter 1-8 NC Bottoming HSS Tap (SKU: 03B163) is a premium-grade cutting tool engineered for industrial professionals who demand accuracy and longevity. Manufactured from superior High-Speed Steel (HSS), this tap is designed to withstand the rigorous demands of metalworking environments. Unlike standard carbon steel taps, Walter's HSS composition retains hardness at higher temperatures, allowing for faster cutting speeds and a significantly longer service life. The tool undergoes a specialized hardening and tempering process, ensuring it maintains a sharp cutting edge even when working with tough materials like stainless steel.

This specific model features a bottoming chamfer, characterized by a very short lead of only 1 to 2 threads. This geometry is critical for threading blind holes—holes that do not pass completely through the workpiece. A bottoming tap allows the user to cut threads almost entirely to the bottom of the hole, maximizing the thread engagement length and ensuring a secure fastener fit. It is typically used as the final step in a three-stage tapping process, following a taper or plug tap, to finish the threads at the bottom of the bore.

Precision is at the core of the Walter 03B163. The threads are precision-ground rather than cut, which provides a smoother finish and reduces friction during the tapping operation. This results in cleaner, more accurate internal threads that meet strict tolerance requirements. Whether you are fabricating new components or repairing damaged threads in maintenance operations, this tap delivers consistent performance across a variety of materials, including aluminum, mild steel, and stainless steel.

Key Technical Benefits

Investing in Walter tooling means investing in efficiency. The superior chip evacuation and reduced friction of the ground threads minimize the risk of tap breakage—a common and costly issue in deep hole tapping. The robust shank and drive square are dimensioned to standard specifications, ensuring compatibility with standard tap handles and tap wrenches. For optimal results, use with a high-quality cutting fluid or tapping paste to further extend tool life and improve surface finish.