Somta Somta Series 551 - HSS Short Hand Tap No.4 UNF Second (Intermediate)

HSS Second (Intermediate) Short Hand Tap No.4 UNF

The SOMTA 5510282 – No.4 HSS Second (Intermediate) Short Hand Tap is a precision-engineered tool designed for general-purpose hand tapping. Manufactured to ISO 529 standards and made from high-speed steel (HSS), this tap produces accurate UNF threads with a 60o flank angle. Its straight flute geometry and right-hand cutting action make it suitable for both through-hole and blind-hole tapping. This second tap is ideal for intermediate thread forming in a 3-piece tap set and is widely used in maintenance, repair, and fabrication environments.

• UNF Thread Form – Unified Fine Thread standard for precision fastenings.
• Second Tap (Intermediate) – Used after taper tap for continued thread cutting and improved alignment.
• High-Speed Steel (HSS) – Offers excellent wear resistance and tool life.
• Straight Flute Design – Supports chip evacuation in hand tapping operations.
• 60o Flank Angle – Delivers accurate, industry-standard thread profiles.
• ISO 2 / 2B Tolerance – Suitable for general-purpose internal threads.
• Right-Hand Cutting – Clockwise cutting motion for standard tap wrenches.
• Blind & Through Hole Capability – Versatile performance across common tapping tasks.
• Manual Tapping – Designed specifically for hand use in workshop settings.

• Part No: 5510004
• Tap Size: No.4 UNF
• Nominal Diameter: 2.85 mm
• Threads Per Inch (TPI): 48
• Overall Length (l1): 48 mm
• Thread Length (l2): 11 mm
• Shank Diameter (d1): 3.15 mm
• Square Size (a): 2.5 mm
• Number of Flutes: 3
• Thread Angle: 60o, UNF Form
• Material: High-Speed Steel (HSS)
• Flute Type: Straight Flute
• Standard: ISO 529
• Tolerance: ISO 2 / 2B
• Cutting Direction: Right-Hand
• Application: General-Purpose Hand Tapping

• Precision Threading – Produces clean, accurate threads for reliable fastener engagement.
• Intermediate Cutting Stage – Bridges the gap between taper and bottoming taps for smooth thread progression.
• Durable HSS Construction – Built for long service life in demanding workshop conditions.