When you need fast, reliable internal threading, this Wiseman Threading Tools Second Lead Metric HSS Tap in M39x4 is engineered to deliver clean, accurate threads with every cut. Crafted from high-speed steel and ground for precision, it’s built to withstand the demands of everyday metalworking while maintaining consistent performance across multiple jobs.

• High-speed steel, ground and uncoated. A robust, general‑purpose tap designed to shrug off heat and wear when paired with standard cutting fluids, keeping thread quality high and setup simple.
• ISO 529 dimensions. Precisely shaped to industry standards, ensuring reliable mating with nuts, bushings, and other components that rely on accurate M39x4 threads.
• Right-hand thread, second lead. The two‑start design advances more material per turn, speeding up tapping without sacrificing thread form—ideal for production runs and quick turnarounds (requires proper alignment and adequate rigidity).
• USA plug lead end. Compatible with common tapping tools found in North American shops for quick, straightforward setup and predictable performance.
• General purpose versatility. Suitable for steel, cast iron, and many nonferrous materials, making it a practical choice for repairs, prototyping, and routine maintenance tasks.

Use cases and practical scenarios:

• In a metalworking shop, you’re machining an internal M39x4 thread inside a 39 mm hole to accept a precision fastener or coupling, with dependable results from first cut to final finish.
• Repair projects where threads are damaged or worn—this tap helps reproduce true thread geometry for secure, reliable assemblies.
• Prototype and production setups where speed matters; the second‑lead design reduces cycle time while preserving thread integrity.

Tips for best results:

• Use a compatible cutting fluid to control heat and improve chip evacuation, then back off slightly to break chips and prevent binding.
• Secure the workpiece firmly to prevent deflection and maintain accurate thread alignment throughout the cut.
• Choose the appropriate pilot and hole size per the M39x4 standard to ensure clean start and full thread engagement.
• Begin with a light touch and progressively increase cutting depth to maintain precise thread geometry and surface finish.

Wiseman Threading Tools stands for precision, consistency, and reliable performance in everyday metalworking tasks. This M39x4 second‑lead HSS tap is a dependable choice for maintenance shops, machine setups, and DIY enthusiasts who demand accurate internal threads and a tool you can trust across multiple projects.