ISO 3338-2:2013

Overview

ISO 3338-2:2013 – Cylindrical shanks for milling cutters - Part 2: Dimensional characteristics of flatted cylindrical shanks is an international standard developed by ISO. It defines the dimensional requirements for flatted cylindrical shanks used in milling cutters. The standard covers shanks with single and double flats, designed to ensure reliable mounting, secure clamping, and global interchangeability. By specifying diameters, lengths, and tolerance classes, ISO 3338-2:2013 supports consistent manufacturing quality and compatibility across the precision tooling and machining industries.

Key Topics

• Dimensional Specifications
  ISO 3338-2:2013 details the dimensions for three forms of flatted cylindrical shanks:

  • Single-flatted shanks (diameters 6 mm to 20 mm)
  • Double-flatted shanks (diameters 25 mm to 63 mm)
  • Shanks with inclined clamping surfaces (diameters 6 mm to 32 mm)

• Applicability to Cutter Types

  • Single-flatted shanks apply to both single-ended and double-ended milling cutters
  • Double-flatted shanks are not suitable for single-ended cutters

• Tolerance Classes
  The standard distinguishes between:

  • h6 tolerance for flatted cylindrical shanks (as per this part)
  • h8 tolerance for plain cylindrical shanks (covered in ISO 3338-1)

• Reference to Other Parts

  • Plain cylindrical shank dimensions are specified in ISO 3338-1
  • Threaded shank dimensions are specified in ISO 3338-3

• Relationship to ISO 13399
  Includes an annex mapping dimensional symbols to ISO 13399 properties for data exchange in tooling databases.

Applications

ISO 3338-2:2013 is essential in industries where milling cutters are a core process component, such as metalworking, automotive manufacturing, and aerospace engineering. The standard’s specifications provide benefits including:

• Tool Manufacturer Guidance
  Ensures compatibility and interchangeability of milling cutter shanks across multiple brands and markets.

• Secure Clamping Solutions
  Flatted shank designs provide improved stability and resistance to rotational forces during usage, supporting higher precision in machining operations.

• Procurement and Quality Assurance
  Manufacturers and buyers can reference ISO 3338-2 standards to verify product dimensions, tolerances, and suitability, streamlining supplier compliance and inspection processes.

• Integration with Digital Tooling Data
  The alignment with ISO 13399 symbol references supports digital integration for computer-aided design (CAD/CAM), tool management systems, and digital manufacturing workflows.

Related Standards

• ISO 3338-1:
  Cylindrical shanks for milling cutters - Part 1: Dimensional characteristics of plain cylindrical shanks
  Covers plain cylindrical shank dimensions and tolerances.

• ISO 3338-3:
  Cylindrical shanks for milling cutters - Part 3: Dimensional characteristics of threaded shanks
  Addresses shanks with threaded ends.

• ISO 2768-1:
  General tolerances - Part 1: Tolerances for linear and angular dimensions without individual tolerance indications
  Defines tolerance classes referenced in ISO 3338-2.

• ISO 13399 (all parts):
  Cutting tool data representation and exchange
  Provides standardized terminology and property mapping for tool dimensions in digital environments.

By following ISO 3338-2:2013, manufacturers and users of milling cutters ensure international consistency, safe tool mounting, and optimized performance in CNC machining and industrial manufacturing processes.