Machine Tap JIS B-4430 Form C 35° Spiral Flute HSSE - NPS 1" x 11.5

• General workshop and production use
• Materials: machinable, unalloyed & low-alloy steels up to 900 N/mm²
• Hole type: optimized for blind holes (35° spiral flute evacuates chips upward)
• Operation: hand tap holders and machine tapping
• Single-cut design for efficient, accurate thread production in one pass

Key benefits:

• Smooth cutting action and high dimensional accuracy
• Reliable chip control, reduced risk of jamming
• HSSE substrate for edge stability and tool life
• Medium lead (Form C) supports a clean thread start in blind holes

• Thread type: NPS (American straight pipe)
• Standard: JIS B-4430
• Form / flute: Form C, 35° spiral flute
• Execution: Single-cut machine tap
• Material: HSSE
• Size: NPS 1" x 11.5
• Overall length (L1): 95 mm
• Thread length (L2): 45 mm
• Shank Ø (D2): 26 mm
• Square: 21 mm
• GTIN (EAN): 4022835997382
• Article No.: 99738

1. Preparation: Drill to the correct core diameter and add a light 30–45° chamfer; clamp securely.
2. Clamping: Fix the tap via the 21 mm square in a suitable hand holder or tapping chuck; check alignment.
3. Lubrication: Apply appropriate cutting oil/coolant to hole and tool.
4. Tapping: Start at low speed with steady feed; keep the tap perpendicular and avoid tilting.
5. Retract & clean: Back out carefully, remove chips and deburr if required.
6. Inspection: Verify with gauges or a mating part; clean the thread.

JIS B-4430 defines dimensions, tolerances and geometries for machine taps to ensure repeatable thread quality and interchangeability.

Form C with 35° spiral flute combines a medium lead with active chip lift. This keeps blind holes clear, protects cutting edges and produces clean thread flanks.

Which materials is it designed for?
Machinable, unalloyed and low-alloy steels up to 900 N/mm².

Is it suitable for blind holes?
Yes. The 35° spiral flute evacuates chips upward, ideal for blind holes.

Hand or machine use?
Both. Use a suitable hand tap holder (square 21 mm) or a tapping chuck on a machine.

What does “single-cut” mean?
Threads are produced in one pass without separate roughing and finishing taps, improving efficiency and accuracy.

Which lubrication is recommended?
Use appropriate cutting oil/coolant for better surface finish, chip control and tool life.