High-Efficiency Threading for Blind Holes in Tough Materials
Our solid carbide spiral flute taps with Unified thread profiles (UNC/UNF) are purpose-built for blind hole threading in materials that are tough, ductile, or require superior chip evacuation. With a left-hand spiral design, these taps lift chips upward and out of the hole, ensuring smooth, burr-free thread formation and reduced tap breakage. Ideal for use in precision CNC operations, especially in aluminum, stainless steel, carbon steel, and non-ferrous alloys.
Crafted from ultra-fine grain tungsten carbide, these taps offer maximum tool life, edge stability, and thermal resistance, making them ideal for high-speed tapping environments with demanding thread quality requirements.
Thread Standard: Unified threads – UNC (coarse) and UNF (fine)
Spiral Flute Design: Optimized for blind holes and efficient chip evacuation
Solid Carbide Substrate: Ensures high rigidity, minimal deflection, and long wear life
Sharp Cutting Edges: Precision-ground flutes enable clean and consistent threads
Excellent Performance in Ductile Materials: Ideal for aluminum, brass, stainless steel, and carbon steel
Threading blind holes in aerospace, automotive, medical device, and electronic component manufacturing
Tapping in CNC machining centers or automated production lines
Suited for aluminum alloys, mild steel, alloy steel, and non-ferrous metals
High-reliability threading in parts that require uniform thread depth and finish
Superior chip evacuation reduces tap breakage in deep blind holes
Clean, precise threads even in sticky or soft metals like aluminum
Performs exceptionally in high-speed and dry cutting environments
Stable thread profile with less torque variation during tapping
Available in both standard sizes and custom geometries upon request
Ensure correct pilot hole diameter and drilling depth
Use lubrication (cutting oil or MQL) to reduce friction and extend tool life
Ideal for use with rigid tapping cycles on CNC machinery
Avoid in extremely abrasive or brittle materials — consider straight flute for those cases
Thread | Prec. | l | L | LC | D | Z | A | LK | K |
NO.2-56UNC | 2B/3B | 1.5P | 42 | 11 | 3 | 2 | 30 | 5 | 2.5 |
NO.2-64UNF | 2B/3B | 1.5P | 42 | 11 | 3 | 2 | 30 | 5 | 2.5 |
NO.3-48UNC | 2B/3B | 1.5P | 42 | 12 | 3 | 2 | 30 | 5 | 2.5 |
NO.3-56UNF | 2B/3B | 1.5P | 42 | 12 | 3 | 2 | 30 | 5 | 2.5 |
NO.4-40UNC | 2B/3B | 1.5P | 52 | 12 | 3 | 3 | 30 | 5 | 2.5 |
NO.4-48UNF | 2B/3B | 1.5P | 52 | 12 | 3 | 3 | 30 | 5 | 2.5 |
NO.5-40UNC | 2B/3B | 1.5P | 52 | 12 | 4 | 3 | 30 | 6 | 3.2 |
NO.5-44UNF | 2B/3B | 1.5P | 52 | 12 | 4 | 3 | 30 | 6 | 3.2 |
NO.6-32UNC | 2B/3B | 1.5P | 52 | 13 | 4 | 3 | 30 | 6 | 3.2 |
NO.6-40UNF | 2B/3B | 1.5P | 52 | 13 | 4 | 3 | 30 | 6 | 3.2 |
NO.8-32UNC | 2B/3B | 1.5P | 55 | 13 | 5 | 3 | 30 | 6 | 4 |
NO.8-36UNF | 2B/3B | 1.5P | 55 | 13 | 5 | 3 | 30 | 6 | 4 |
NO.10-24UNC | 2B/3B | 1.5P | 60 | 15 | 5 | 3 | 30 | 6 | 4 |
NO.10-32UNF | 2B/3B | 1.5P | 60 | 15 | 5 | 3 | 30 | 6 | 4 |
NO.12-24UNC | 2B/3B | 2.5P | 65 | 15 | 6 | 3 | 30 | 7 | 4.5 |
NO.12-28UNF | 2B/3B | 2.5P | 65 | 15 | 6 | 3 | 30 | 7 | 4.5 |
1/4-20UNC | 2B/3B | 2.5P | 65 | 17 | 6 | 3 | 30 | 7 | 4.5 |
1/4-28UNF | 2B/3B | 2.5P | 65 | 17 | 6 | 3 | 30 | 7 | 4.5 |
5/16-18UNC | 2B/3B | 2.5P | 72 | 20 | 6.1 | 3 | 30 | 8 | 5 |
5/16-24UNF | 2B/3B | 2.5P | 72 | 20 | 6.1 | 3 | 30 | 8 | 5 |
3/8-16UNC | 2B/3B | 2.5P | 75 | 22 | 7 | 3 | 30 | 8 | 5.5 |
3/8-24UNF | 2B/3B | 2.5P | 75 | 22 | 7 | 3 | 30 | 8 | 5.5 |
7/16-14UNC | 2B/3B | 2.5P | 83 | 25 | 8 | 3 | 30 | 9 | 6 |
7/16-20UNF | 2B/3B | 2.5P | 83 | 25 | 8 | 3 | 30 | 9 | 6 |
1/2-13UNC | 2B/3B | 2.5P | 90 | 25 | 9 | 4 | 15 | 10 | 7 |
1/2-20UNF | 2B/3B | 2.5P | 90 | 25 | 9 | 4 | 15 | 10 | 7 |
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