Osg 1650503408 Spiral Flute Tap 1/2-20 Unf 3 Flutes

Product Description

The OSG 1650503408 is a spiral flute tap designed for threading 1/2-20 UNF internal threads in a wide range of ferrous and non-ferrous materials. Built from powdered metal (grade PMT15) and finished with a TICN coating, this tap delivers extended tool life in demanding production and maintenance environments. The 45-degree right-hand helix angle drives chips up and out of the hole, making it well suited to blind-hole applications. The modified bottoming chamfer allows threading close to the bottom of a bore. Thread fit is 2B class with an H5 thread limit, meeting standard UNF tolerance requirements. Licensed HVAC technicians, machinists, and maintenance professionals working with tapped assemblies will find this tap ready for direct use.

This tap is appropriate for threading blind holes in alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel. It fits production tapping operations as well as field maintenance and repair work where precise UNF thread geometry is required. The 55 mm neck length and 49.00 mm tapping depth accommodate moderate hole depths without interference. With a 3-flute spiral configuration, this tap maintains stable cutting action across varying workpiece hardness levels encountered in industrial and mechanical service settings.

Key Features

• 1/2-20 UNF thread form, right-hand direction, 2B class of fit with H5 thread limit
• 45-degree right-hand spiral flute geometry evacuates chips from blind holes
• Modified bottoming chamfer for threading close to the bottom of a bore
• Powdered metal construction (grade PMT15) provides wear resistance in hard and abrasive materials
• TICN coating reduces friction and extends tool life across multiple material types
• Broad material compatibility including stainless steel, hardened steel, cast iron, and aluminum alloys

Compatibility

Designed for use in alloy steel, aluminum, cast aluminum, cast iron, hardened steel, high-carbon steel, low-carbon steel, medium-carbon steel, and stainless steel workpieces requiring a 1/2-20 UNF tapped hole. Part of OSG Series 16505.

Installation Notes

Tapping operations should be performed by qualified machinists or maintenance technicians familiar with proper speeds, feeds, and cutting fluid selection for the workpiece material. Ensure the workpiece is securely fixtured and the tap is properly aligned with the drilled hole before engagement to avoid tap breakage. Use a cutting fluid or tapping compound appropriate to the material being threaded. Inspect the tap for wear or chipping before each use and replace if thread form or chamfer shows damage.