Value Collection MSC-04424420 Straight Flute Tap 4-40 Unc

Product Description

The VALUE COLLECTION MSC-04424420 is a straight flute tap designed to cut internal threads in through-holes and open-chip applications. Built from high-speed steel (HSS) with a bright, uncoated finish, it produces 4-40 UNC right-hand threads with a taper chamfer entry that guides the tap smoothly into the workpiece. The three-flute design provides good chip clearance in softer materials including aluminum, mild steel, and plastics. With an overall length of 1.875 inches and a thread length of 0.5625 inches, this tap is sized for small-diameter threading work common in electronics, instrumentation, and light mechanical assemblies. The H2 thread limit ensures accurate fit to 2B and 3B class-of-fit tolerances.

This tap is suited for hand tapping and low-speed machine tapping in production and maintenance environments. The 4-40 UNC thread size is widely used in electronics enclosures, circuit board standoffs, instrument panels, and small mechanical fastener applications. The taper chamfer — typically 8 to 10 threads of lead — makes it appropriate for starting threads in through-holes where a gradual lead-in reduces the risk of tap breakage. Machinists, tool and die makers, and maintenance technicians working with small-fastener assemblies will find this tap well suited to bench work and light CNC or drill-press tapping.

Key Features

• 4-40 UNC thread form with right-hand cut for standard small-fastener applications
• High-speed steel construction provides good hardness and wear resistance across a range of workpiece materials
• Taper chamfer entry eases thread starting and reduces tap breakage risk in through-holes
• H2 thread limit holds 2B and 3B class-of-fit tolerances for reliable fastener engagement
• Three-flute geometry supports chip evacuation in softer and medium-hardness materials
• Bright uncoated finish suits general-purpose use without added coating cost

Compatibility

Designed as a general-purpose replacement or stock tap for any application requiring 4-40 UNC internal threads at 2B or 3B class of fit.

Installation Notes

Use the correct tap drill size for 4-40 UNC threads before tapping to ensure proper thread engagement and to avoid tap breakage. Apply cutting fluid appropriate for the workpiece material when hand tapping or machine tapping. When using in a drill press or tapping machine, keep spindle speed low for small-diameter taps and back off periodically to break chips. Inspect the tap for wear or chipping before each use, as small-diameter HSS taps are susceptible to breakage if forced into an undersized or misaligned hole.