Collet ER32 FORTIS, inner diameter 4 mm, DIN 6499 standard

FORTIS ER32 collet with a 4 mm inner diameter manufactured according to DIN 6499 provides precision clamping for tools with a 4 mm shank. Intended for use in ER32 toolholders, this collet ensures concentric grip and repeatable positioning for milling, drilling and other machining tasks. Its DIN 6499 compliance means it fits ER32 systems and holders designed for that standard, making it compatible with many CNC spindles and manual toolholders that accept ER32 collets.

Advantages

The collet delivers accurate concentric clamping with low runout, which improves surface finish and tool life in precision operations. Its standardized geometry provides reliable interchangeability with other DIN 6499 ER32 components, simplifying tool setup and maintenance. Manufactured to consistent tolerances, the collet offers stable grip force for short and medium machining cycles and supports safe and repeatable tool changes.

Suitable for

• Clamping 4 mm shank end mills and drills
• ER32 toolholders in CNC milling machines
• Precision machining and finishing operations
• Tool setups that require DIN 6499-compatible collets

Key specifications

• Collet system: ER32 (DIN 6499 geometry)
• Inner diameter (nominal): 4 mm for 4 mm shank tools
• Material: hardened and ground steel suitable for machining collets
• Clamping type: concentric slotted collet for axial and radial gripping
• Typical application: milling, drilling, reaming and light turning in toolholders

How to use

Insert the collet into the matching ER32 nut or toolholder and ensure it seats fully against the holder face. Place the 4 mm shank tool into the collet so the tool shoulder or the desired insertion depth is aligned with the holder. Hand-tighten the nut to hold the tool, then torque to the toolholder manufacturer's recommended value using the appropriate wrench. Confirm runout and seating before beginning machining; recheck clamping after the first cut or initial run-in.

Usage recommendations

Use clean, dry mating surfaces and avoid dirt or chips when installing the collet to maintain repeatable accuracy. Replace collets that show wear, corrosion, or deformation. For best results, use with toolholders and spindles specified for ER32/DIN 6499 components and follow the machine manufacturer's torque and safety guidelines.