Somta Somta Series 541 - HSS Straight Flute Short Hand Bottom (Finishing) Tap UNC 1 3/8" x 6 TPI

HSS Bottom Tap UNC 1-3/8’ x 6 – Somta Series 541

The SOMTA 5413493 – 1-3/8’ x 6 UNC HSS Bottom Tap is a heavy-duty threading tool designed for precise thread cutting at full depth in blind holes. Manufactured from high-speed steel (HSS), it features a short chamfer ideal for threading close to the bottom of a drilled hole. Conforming to the Unified National Coarse (UNC) thread profile, this tap delivers accurate and clean threading performance in a wide variety of industrial and fabrication applications.

• Bottoming Chamfer (1-2 Threads) – Optimized for threading to full depth in blind hole applications.
• Unified National Coarse (UNC) – 1-3/8’ diameter with 6 TPI for coarse-thread fastener compatibility.
• Straight Flute Geometry – Provides controlled chip flow and consistent cutting action.
• High-Speed Steel (HSS) – Delivers superior durability and cutting efficiency under high-load conditions.
• Bright Finish – Minimizes friction and promotes smoother threading.
• Versatile Tapping – Suitable for use with tap wrenches, tapping machines, and other threading tools.

• Part No: 5413493
• Thread Size: 1-3/8’ x 6 TPI
• Thread Standard: UNC – Unified National Coarse
• Tap Type: Bottoming (short chamfer for blind holes)
• Flute Style: Straight flute
• Cutting Direction: Right-hand
• Material Finish: High-Speed Steel (HSS), Bright
• Standard: ANSI / Unified Inch

• Maximum Thread Engagement – Reaches near the bottom of blind holes for strong thread integrity.
• Coarse Thread Capability – Suited for applications requiring robust, high-load threads.
• Reliable HSS Tooling – Built to withstand demanding industrial use over time.
• Trusted by Professionals – Ideal for machining, repair, and heavy fabrication work.

The SOMTA 5413493 bottom tap is the professional’s choice for accurate coarse-thread tapping in large-diameter blind holes. Engineered from tough HSS and designed for precision, it delivers consistent performance across steel, aluminum, and other machinable metals.