Widia Gtd VTSFT-TC5151 Spiral Flute Tap 5/16"-18 Bottoming 2 Flutes UNJC pneumatic accessory

Precision thread cutting for UNC applications

The Widia Gtd VTSFT-TC5151 spiral flute tap produces 5/16"-18 UNC threads in a bottoming configuration. High-speed steel construction with a black oxide finish resists wear during repetitive machining tasks. Three flutes evacuate chips efficiently while maintaining alignment in through-hole or blind-hole work. This tool suits maintenance technicians and metalworkers who need reliable internal threading.

Heat and wear management in daily use

The black oxide surface treatment reduces friction between the tap and workpiece, limiting temperature rise during extended cutting cycles. High-speed steel retains hardness at the elevated temperatures typical of steel and alloy threading. Three-flute geometry distributes cutting forces evenly, lowering the torque spike that can cause chatter or premature dulling. No external lubrication system is required beyond standard cutting fluid practice.

Replaces worn or undersized taps in UNC workflows

This tap replaces a dull or damaged 5/16"-18 UNC bottoming tool when thread quality falls below 2B class-of-fit requirements. The H5 thread limit and 75 percent thread drill size F match standard UNC specifications, so the upgrade is worthwhile when existing taps no longer hold tolerance. It does not address metric, UNF or pipe-thread needs, nor does it suit high-volume CNC operations that demand coated carbide tooling.