Drillco construction reamer details
Drillco 3pc Set 1/2–3/4 Spiral Flute 1/2 Shank Nitro Construction Reamer (427N3S)
Drillco 427N3S 3pc Set 1/2–3/4 Spiral Flute 1/2 Shank Nitro Construction Reamer is a set of heavy-duty Nitro construction reamers designed for precise and efficient reaming in structural steel assembly fabrication. The Nitro surface treatment provides a hard, protective layer that increases hardness without brittleness, and the black and gold finish ensures maximum lubricity. Made from premium grade cobalt HSS, these reamers drill harder materials approximately 30% faster than standard HSS. The tapered points allow smooth entry into misaligned holes, while the 3-flats reduced shank ensures a secure grip during operation. Ideal for demanding industrial applications, this set delivers durability, accuracy, and reliable performance.
Nitro surface treatment increases hardness and lubricity
Premium grade cobalt HSS for drilling harder materials
Self-centering 135° split-point reduces walking and thrust
Black and gold finish provides high lubricity
3-flats reduced shank for secure chuck grip
Most common countersink angles available: 60°, 82°, 90°
4 flutes for improved material removal and surface finish
Longer shank suitable for use in turret lathes
Set of three sizes for versatility in construction tasks
Enables precise and efficient reaming in heavy-duty applications
Improved chip removal and surface finish
Durable and reliable for repeated industrial use
Technical Specifications:
Sizes: 1/2", 5/8", 3/4"
Type: Spiral Flute Nitro Construction Reamer Set
Shank Size: 1/2"
Point Type: Tapered point, 135° split-point
Material: Premium grade cobalt HSS
Surface Treatment: Nitro, black and gold finish
Shank Style: 3-flats reduced shank
Applications: Fabrication of structural steel assemblies
Product identification
- Brand: Drillco
- Model / MPN: 427N3S





