Widia Gtd VTSFT-TC5138 Spiral Flute Tap #6-40 Bottoming 2 Flutes UNJF pneumatic accessory

Thread cutting tool for UNJF fasteners

The Widia VTSFT-TC5138 is a spiral flute tap designed to cut internal threads in #6-40 UNJF specifications. It suits maintenance technicians and machinists producing precision threaded holes in aerospace or automotive components. The high-speed steel construction provides durability for repeated use in production environments. Right-hand thread direction matches standard fastener requirements.

Capacity defined by #6-40 UNJF specification

This tap creates threads to a Class 3B fit with an H3 thread limit using a #33 drill size at 75 percent thread engagement. The 3/8 inch thread length and 2 inch overall length determine the maximum depth of cut. Two flutes provide chip evacuation in blind holes where the bottoming chamfer reaches full thread depth. Material hardness and machine rigidity define practical limits beyond the stated dimensions.

Replaces worn or incorrect thread cutting tools

The tap upgrades from general-purpose taps when UNJF thread form and Class 3B fit are required for critical assemblies. It replaces damaged bottoming taps in #6-40 size to restore accurate thread production. The jump is justified when existing tooling cannot achieve the specified thread limit or when flute geometry causes chip packing in blind holes. Not for through-hole applications or larger thread sizes.