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03B086 - Walter 1/2-20 UNF HSS Bottoming Tap for Blind Holes

Packaging: 3 per each
$43.60/ea

Package Price:

$130.80/3 per each

Usually ships within 3-5 business days

SKU: 03B086 Categories: ,

OVERVIEW

Precision Threading with Walter High Speed Steel Taps

The Walter 03B086 1/2-20 NF Bottoming Tap is a premium-grade cutting tool designed for industrial professionals who demand accuracy and longevity. Manufactured from top-tier High Speed Steel (HSS), this tap is engineered to withstand the high thermal stresses and abrasive nature of cutting threads in tough metals like stainless steel, mild steel, and aluminum alloys. Unlike carbon steel alternatives, Walter's HSS composition ensures the cutting edges remain sharp longer, reducing the frequency of tool changes and ensuring consistent thread quality over the tool's lifespan.

This specific model is a "Bottoming" tap, characterized by its very short chamfer length of just 1 to 1.5 threads. This geometry is critical for specific machining operations: threading blind holes. A blind hole is one that does not pass completely through the workpiece. Standard taper or plug taps have longer tapered leads that prevent full thread depth at the bottom of such holes. The Walter bottoming tap is designed to be used after a plug tap has cleared the majority of the material, allowing the operator to cut threads all the way to the bottom of the hole, maximizing thread engagement and fastener holding power.

The 1/2-20 NF (National Fine) thread profile offers distinct mechanical advantages, including higher tensile strength and better resistance to vibration loosening compared to coarse threads. This makes the Walter 03B086 an essential tool for fabricating high-stress components in automotive, aerospace, and heavy machinery maintenance. Whether used in a manual tap wrench or a machine setup, this tool delivers the smooth, precise cutting action that Walter Surface Technologies is known for.

Key Technical Benefits

  • Blind Hole Capability: Short chamfer allows threading within millimeters of the hole's bottom.
  • Material Versatility: Effective on ferrous and non-ferrous metals, including hardened alloys.
  • Precision Grinding: Ensures tight tolerances for Class 2B or 3B thread fits.
Additional Information
Packaging Description:1 per each, 3 per each
Brand:Walter
Used to Cut:Steel or Stainless or Aluminum
Thread Size:1/2-20 NF
Tap Style:Bottoming
Material:High Speed Steel (HSS)
Thread Standard:NF (National Fine)

INCLUDED

  • 1 x Walter 1/2-20 NF High Speed Steel Bottoming Tap

APPLICATIONS

  • Threading blind holes in steel, stainless steel, and aluminum
  • Automotive repair requiring 1/2-20 NF threads
  • Machining and fabrication of custom parts
  • Repairing damaged or stripped threads
  • Final thread finishing after plug tapping

FAQ

A bottoming tap has a very short chamfer (1-1.5 threads) and is used to cut threads to the bottom of a blind hole. A plug tap has a longer chamfer (3-5 threads) and is easier to start but cannot thread all the way to the bottom.

For a 1/2-20 NF thread, the recommended drill bit size is typically 29/64 inch. This provides the correct percentage of thread engagement for a strong hold.

Yes, this Walter tap is made from High Speed Steel (HSS), which is durable enough to cut threads in stainless steel, mild steel, and aluminum.

Yes, using a high-quality tapping fluid or cutting oil is highly recommended. It reduces friction, dissipates heat, and extends the life of the tap while producing cleaner threads.

It is difficult to start a new hole with a bottoming tap because it lacks a tapered lead to align itself. It is best practice to start the thread with a taper or plug tap and finish with the bottoming tap.

NF stands for National Fine. It indicates that the thread pitch (20 threads per inch) is finer than the standard coarse thread (NC) for a 1/2-inch diameter.

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