Osg 1003100 Straight Flute Tap 5-40 Unc Hss Plug

Product Description

The OSG 1003100 is a straight flute plug tap designed for threading 5-40 UNC holes in a range of ferrous and non-ferrous materials. It features 3 straight flutes and a plug chamfer, making it suited for through-hole tapping operations where chips can exit freely ahead of the tap. Manufactured from high-speed steel (HSS) with a bright, uncoated finish, it delivers consistent thread quality in light-duty to medium-duty production and maintenance applications. Overall length is 1-15/16 inches with a thread length of 5/8 inches. Licensed machinists, tool-and-die makers, and maintenance technicians are the primary users of this tap.

This tap is suited for threading 5-40 UNC holes in aluminum, cast aluminum, cast iron, high-carbon steel, low-carbon steel, and medium-carbon steel. The plug chamfer (approximately 3-5 thread lead) allows it to start easily in a pre-drilled hole and is appropriate for both through-hole and deeper blind-hole applications where some thread runout is acceptable. It performs reliably in both manual hand-tapping setups and light machine tapping operations on drill presses or CNC machining centers with appropriate tapping attachments.

Key Features

• 5-40 UNC thread form with right-hand thread direction and H1 thread limit for controlled fit tolerance
• 3 straight flutes for chip clearance in through-hole tapping applications
• Plug chamfer provides easy starting and smooth threading in a variety of materials
• High-speed steel construction offers good wear resistance for general-purpose tapping
• Bright, uncoated finish suitable for use with standard cutting fluids
• No coolant-through requirement simplifies tooling setup

Compatibility

Designed as an OEM-style replacement or standard tooling option for any application requiring a 5-40 UNC straight flute plug tap in high-speed steel. Compatible with standard tap holders and collets sized for a 0.141-inch shank diameter.

Installation Notes

Always use the correct tap drill size for a 5-40 UNC thread before tapping. Secure the workpiece and ensure the tap is aligned perpendicular to the drilled hole to prevent tap breakage. Apply an appropriate cutting fluid for the material being tapped. In machine tapping, use a tapping attachment or floating holder to reduce the risk of thread damage and tap breakage.