Hand Tap set of 3 pieces ISO 529 HSS-G left hand thread - UNC 3/4 x 10 LH

This hand tap set is perfectly suited for:

• General Use: In the workshop, in skilled trades, and in industry.
• Materials: Ideal for well-machinable materials up to 900 N/mm², such as unalloyed and low-alloy steels.
• Holes: For cutting threads in through holes and blind holes.
• Usage Type: Specially optimized for manual use with a tap wrench.

The set consists of three perfectly coordinated taps, each cutting a specific part of the thread. Important: This set is designed for left-hand threads, which are tightened by turning counter-clockwise.

• Taper Tap (Vor): With one ring marking on the shank. This tap starts the cut and cuts the first threads.
• Second Tap (Mittel): With two ring markings. It deepens the pre-cut thread.
• Bottoming Tap (Fertig): Without a ring marking. It cuts the thread to its final depth and correct profile, indispensable for blind holes.

Thread Type UNC: The abbreviation stands for "Unified National Coarse" and describes an American coarse thread according to the ANSI B 1.1 standard. It is often used for connections where high strength and easy assembly are a priority. The designation UNC 3/4 x 10 LH means:

• 3/4: The nominal diameter of the thread in inches (approx. 19.05 mm).
• 10: The number of threads per inch (tpi).
• LH: Stands for "Left Hand" and indicates a left-hand thread.

Standard ISO 529: This international standard defines the dimensions of hand taps, particularly the length, diameter, and square drive. Compliance with this standard ensures that the tap fits into standard tap wrenches with the correct square drive (in this case, 11.2 mm), which enables safe and effective handling.

ANSI B 1.1: This is an American standard that specifies the exact specifications of Unified threads (like UNC), including the profile shape, tolerances, and dimensions. VÖLKEL therefore combines the thread type according to the American standard (ANSI) with the tap dimensions according to the international standard (ISO) to create a precise and compatible tool.

1. What do "UNC" and "LH" mean?

UNC stands for "Unified National Coarse," a coarse thread widely used in the USA. "LH" stands for "Left Hand" and denotes a left-hand thread. Unlike a right-hand thread, this one is tightened by turning counter-clockwise.

2. Why do I need a 3-piece set?

A 3-piece set allows for a step-by-step cutting of the thread, which reduces the load on the tool and ensures a clean and dimensionally accurate result. The taper tap starts the cut, the second tap deepens it, and the bottoming tap brings the thread to its final shape.

3. What does the material HSS-G mean?

HSS-G stands for "High Speed Steel, Ground." The "G" means that the cutting surfaces are precisely ground. This ensures sharper edges, higher dimensional accuracy, and a longer tool life compared to unground (HSS-R) tools.

4. What is the difference between this set and machine taps?

This set is specifically designed for manual use with a tap wrench. Machine taps often have a different geometry (e.g., spiral flutes or points) for automatic chip evacuation and are optimized for use in a drill press or tapping machine.

5. How do I identify the individual taps in the set?

The taps are identified by ring markings on the shank end: The taper tap (for starting) has one ring, the second tap (for deepening) has two rings, and the bottoming tap (for finishing) has no rings. This applies to both right-hand and left-hand threads.