Wiseman Threading Tools Second Lead Metric HSS Tap Left Hand - M24x1 is a precision hand-tap engineered for clean, reliable metric left-hand threading. Ground high-speed steel, uncoated for general-purpose use, this tap follows ISO 529 dimensions and is designed for robust performance in metalworking applications that require a true left-hand thread with efficient material removal. The “second lead” design (often referred to in industry as a plug/second lead) helps you cut deeper threads in fewer passes, speeding up your work without sacrificing accuracy. (USA plug lead)

• Materials and standards: High-speed steel ground tap that’s uncoated for versatile use across steels, cast irons, and non-ferrous materials. Sized to ISO 529 dimensions, ensuring compatibility with standard cutting drills and threading tools.
• Thread direction and lead: Left-hand thread with a second lead, enabling efficient chip ejection and quicker progression into deeper holes. This configuration is ideal when the application requires reverse-threaded fasteners or assemblies that resist loosening under vibration.
• Size and fit: M24x1 form, designed to create precise metric threads with a 24 mm major diameter and 1 mm pitch. The tool is built to deliver consistent thread form in a single hole, reducing trial-and-error attempts.
• Construction and usability: Hardened, ground flanks provide repeatable cuts and extended life in demanding shop conditions. A conventional tap body and drive end are compatible with standard tap wrenches, promoting straightforward hand tapping and light machine tapping workflows.
• Ideal for professionals and hobbyists: Perfect for machinists, maintenance technicians, and fabricators who need reliable left-hand metric taps for repair work, fixture construction, or components that rely on reverse-threaded fasteners.

Why this Wiseman tap stands out: the combination of high-speed steel, precise ISO 529 geometry, and the second-lead design translates to faster threading with smooth chip clearance. The uncoated finish invites you to pair it with your preferred cutting fluid or oil, maximizing tool life without the constraints of coatings that can trap debris in tough jobs. For anyone tackling left-hand threads, this tap offers predictable performance and repeatable results in a wide range of metals.

Use cases and practical tips

• Use in straight, properly aligned holes for clean, true threads. Begin with light, steady cuts and maintain even pressure to avoid cross-threading.
• Lubricate generously with a suitable cutting oil to reduce heat and extend tap life; back off slightly to break chips and prevent tap binding.
• Apply gentle, consistent motion when cutting left-hand threads—rotate in the direction appropriate for your left-hand application and back off as needed to clear chips.
• Pair with a robust tap wrench or handle for precise control, especially in larger sizes like M24 where stability matters for thread accuracy.

In practice, this Wiseman left-hand, second-lead HSS tap is a dependable choice when you need strong, accurate left-handed metric threads in steel and similar materials. Its design supports efficient work in repair and fabrication environments where reverse-threaded assemblies are common, while ISO 529 compliance ensures compatibility with standard tooling and gauges in professional shops.