Thread Mills

Thread Mills

Made in USA since 1992

Which thread do you need?

NPS Pipe Threads
NPS Pipe Threads
UN Threads
UN Threads Unified inch threads, coarse and fine 3, 4 and 5 flute options Best for Standard inch threading, blind or through
UN Threads - Single Form
UN Threads - Single Form
UN Threads - Coolant Through
UN Threads - Coolant Through Same UN threads, coolant fed to the cut Clears chips in deep and blind holes Best for Deep holes and lights-out production
NPT Pipe Threads
NPT Pipe Threads Standard tapered pipe thread Sealed with tape or thread compound Best for General pipe and fitting work
NPTF Pipe Threads
NPTF Pipe Threads Dryseal variant of NPT Crests crush to seal metal-to-metal Best for Hydraulic and fuel lines, no sealant
Metric Threads
Metric Threads ISO metric, multiple pitches per diameter 3, 4 and 5 flute options Best for Metric threading from M4 upward

Thread mills cut internal or external threads using a helical milling path rather than a traditional tap, which reduces the risk of tool breakage in blind holes and hardened materials while allowing one tool to cut multiple thread sizes when paired with the right program. We stock thread mills for UN Threads (including coolant-through versions for improved chip evacuation), NPT Pipe Threads, NPTF Pipe Threads, and Metric Threads.

Because thread milling doesn't rely on axial tap pressure to form threads, it's often the preferred method for hardened steels, thin-walled parts, and large-diameter threads where tapping risks breakage. All thread mills are manufactured in the USA.

  • Compare SKU Vendor Cutter Diameter Thread Size (D1) Shank Diameter (D2) Thread Length (L2) Overall Length (L1) Thread Type Number of Flutes Coating In Stock Price Quantity
    A79020 ACT 0.6200 1/2-14 5/8 1.1500 3-1/2 NPS Pipe Thread 5 ALTiN 18
    $450.80
  • A79021 ACT 0.6200 3/4-14 5/8 1.1500 3-1/2 NPS Pipe Thread 5 ALTiN 19
    $450.80
  • A79022 ACT 0.7450 1-11-1/2 3/4 1.3650 4 NPS Pipe Thread 5 ALTiN 23
    $536.11
  • A42771 ACT .620 1-11-1/2 3/4 1.125 4 NPTF Pipe Thread 5 Uncoated 71
    $451.59
  • A42764 ACT .620 1-11-1/2 3/4 1.125 4 NPT Pipe Thread 5 Uncoated 67
    $451.59
  • A50087 ACT .620 1-11-1/2 3/4 1.125 4 NPTF Pipe Thread 5 ALTiN 11
    $479.09
  • A50080 ACT .620 1-11-1/2 3/4 1.125 4 NPT Pipe Thread 5 ALTiN 20
    $479.09
  • A42756 ACT .495 3/4-10 1/2 1.250 3-1/2 UN Thread Coolant Through 4 Uncoated 11
    $466.15
  • A42757 ACT .495 3/4-16 1/2 1.250 3-1/2 UN Thread Coolant Through 4 Uncoated 31
    $466.15
  • A71252 ACT .495 3/4-16 1/2 1.250 3-1/2 UN Thread Coolant Through 4 ALTiN 12
    $484.00
  • A42741 ACT .620 7/8-9 5/8 1.250 3-1/2 UN Thread 5 Uncoated 81
    $456.00
  • A50070 ACT .620 7/8-9 5/8 1.250 3-1/2 UN Thread 5 ALTiN 13
    $478.11
  • A42742 ACT .620 7/8-14 5/8 1.250 3-1/2 UN Thread 5 Uncoated 89
    $456.00
  • A50071 ACT .620 7/8-14 5/8 1.250 3-1/2 UN Thread 5 ALTiN 8
    $478.11
  • A42743 ACT .620 1-8 3/4 1.375 4 UN Thread 5 Uncoated 100
    $451.59
  • A50072 ACT .620 1-8 3/4 1.375 4 UN Thread 5 ALTiN 14
    $479.09
  • A42744 ACT .620 1-12 3/4 1.375 4 UN Thread 5 Uncoated 100
    $451.59
  • A50073 ACT .620 1-12 3/4 1.375 4 UN Thread 5 ALTiN 18
    $479.09
  • Total: items /

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