SPIRAL TAPS METRIC SUTTON

Sutton Tools metric spiral flute taps are high-performance machine taps designed specifically for power tapping in blind holes, engineered to pull metal chips up and out of the hole to prevent tap breakage. Understanding the Technical Specifications M8 (Major Diameter): The tap creates a thread with a nominal outer diameter of exactly 8 millimeters. 1.25 (Thread Pitch): The distance from the peak of one thread crest to the next is 1.25 millimeters. This is the standard "Metric Coarse" pitch for an 8mm fastener. Spiral Flute (The Geometry): Instead of straight grooves, the flutes twist around the tool body like a drill bit. This helical design lifts metal chips up and out of the hole toward the entry point. It prevents chips from packing at the bottom, which is the leading cause of broken taps in blind holes. Essential Operational Rules Pre-Drill Hole Size: You must pre-drill the hole using a 6.8 mm drill bit. Drilling a 7.0 mm hole will result in weak, shallow threads, while a 6.5 mm hole will bind and snap the tap. Lubrication: Never run a spiral flute tap dry. Use a dedicated cutting fluid or tapping paste (like Sutton's Tapping Fluid or Rocol) to reduce heat and friction. Machine Speed: Spiral flute taps are meant to run in a continuous forward motion. Avoid the "back-and-forth" hand-tapping method, as reversing prematurely can crush the delicate chips currently lifting up the spiral flutes