Osg 1746201 Spiral Flute Tap M16x2.00 Metric Coarse 6H

Product Description

The OSG 1746201 is a spiral flute tap designed for cutting internal metric threads in a range of ferrous materials. Built from vanadium high-speed steel (HSS) with a steam oxide coating, it delivers durability and chip evacuation performance in demanding tapping applications. The tap features a 45-degree helix angle that drives chips up and out of the hole — a critical advantage when working in blind holes. It is sized for M16x2.00 metric coarse threads and carries a 6H class of fit with a D7 thread limit, producing threads suitable for standard metric fastener assemblies. Licensed trades machinists, tool-and-die workers, and industrial maintenance technicians are the primary users.

This tap is suited for blind-hole and through-hole tapping in stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. The modified bottoming chamfer allows threading closer to the bottom of a blind hole compared to plug or taper configurations. With an overall length of 3.8125 inches and a thread length of 1.8125 inches, it fits standard tap holders and CNC tooling setups used in production and maintenance machining environments. The Series 343 designation places it within the OSG general-purpose spiral flute tap family.

Key Features

• M16x2.00 metric coarse thread profile with 6H class of fit and D7 thread limit
• 45-degree right-hand spiral flute design evacuates chips upward out of the hole
• Modified bottoming chamfer for threading close to the base of blind holes
• Vanadium high-speed steel construction for wear resistance in ferrous materials
• Steam oxide coating reduces friction and provides light corrosion resistance during storage
• 3-flute geometry balances chip load and cutting speed in medium-to-hard steels

Compatibility

Rated for use in stainless steel, high-carbon steel, low-carbon steel, and medium-carbon steel. Compatible with standard tap holders accepting a shank diameter of 0.255 inches. Coolant-through capability is not supported by this tap.

Installation Notes

Installation should be performed by qualified machinists following standard tapping procedures. Ensure the workpiece is securely fixtured and the pre-drilled hole diameter matches the recommended tap drill size for M16x2.00 before beginning. Apply appropriate cutting fluid for the workpiece material, particularly when tapping stainless steel, to prevent galling and tap breakage. Do not reverse the tap to break chips — the spiral flute geometry is designed to eject chips continuously during forward rotation.