Milwaukee Tool 49-57-5168 Straight Flute Tap 9/16-18 Unf

Product Description

The MILWAUKEE TOOL 49-57-5168 is a straight flute tap designed to cut internal 9/16-18 UNF threads in metal workpieces. It is manufactured from high-carbon steel with a black oxide coating that reduces friction and provides mild corrosion resistance during use. The plug chamfer style — with a moderate lead-in of several tapered threads — makes this tap suitable for through-holes and most standard threading applications. With four flutes and a right-hand thread direction, it produces clean, consistent threads when used at appropriate speeds with cutting fluid. Machinists, pipefitters, maintenance technicians, and field tradespeople install this tap by hand or with a tap wrench in repair and fabrication work.

This tap is used wherever a 9/16-18 UNF internal thread must be cut or restored in a drilled or bored hole. The fine-thread UNF standard makes it common in automotive, HVAC equipment, and mechanical assembly applications where higher thread engagement or vibration resistance is required compared to coarse-thread UNC. At 3.25 inches overall length, it fits standard tap handles and T-handle wrenches used in both shop and field settings. Typical materials tapped include mild steel, aluminum, and similar machinable metals.

Key Features

• 9/16-18 UNF right-hand thread specification for fine-thread applications
• Plug chamfer provides moderate lead-in, suitable for through-holes and most blind-hole work with adequate depth
• Four-flute design channels chips efficiently during the threading cut
• High-carbon steel construction delivers hardness needed for cutting threads in common metals
• Black oxide coating reduces friction and provides light surface protection
• Class of fit 2B produces standard tolerance threads compatible with most commercial fasteners

Compatibility

Designed as an OEM-style hand tap for cutting or restoring 9/16-18 UNF internal threads in standard machinable materials. Fits tap handles and T-handle wrenches that accept a 0.375-inch square or round shank.

Installation Notes

Always drill the correct tap drill size for 9/16-18 UNF before starting the tap to avoid breakage. Apply cutting fluid throughout the threading operation and back the tap off periodically to break and clear chips. Never force a tap against hard resistance — back it out, clear chips, and reapply fluid. All threading work should follow applicable shop safety practices and, where relevant, OSHA machine guarding and hand-tool safety guidelines.