Carmex External Right Hand Stub ACME Thread Turning Insert 3 TPI / 27 ER 3 STACME BMAExternal Thread Turning Insert Stub ACME Profile (3 TPI) The 27 ER 3 STACME BMA is a high performance external threading insert designed for Stub ACME thread profiles, ideal for power transmission, lead screws, and other linear motion components where high load bearing capacity and smoother thread engagement are critical. With a 3 TPI pitch, this insert is optimized for coarse, trapezoidal threads with enhanced efficiency and strength. Constructed

✔ Industry-Leading Technology – Manufactured with assistance from Ceratizit

the STI (Screw Thread Insert) tap

Bottoming Chamfer (1–2 Threads) – Enables full-depth thread cutting in blind-hole applications

Part Number: 20256

even under heavy use

making it ideal for high-speed production tapping

and long tool life in both manual and machine applications

296mm Overall Length - L

✔ Perfect for Larger Material Removal – Designed for fast and efficient cutting

With a pitch of 1

high-precision threading suitable for mechanical and general-purpose applications

Supplied with setting standards (except 0-1")