ER Collet

ER Collet clamping systems

ER16, ER20, ER25, ER32 and ER40 collets for straight-shank tools

ER collet clamping systems are widely used in all machining sectors and extensively for straight-shank diamond tools.
The ‘ER’ numbers are loosely associated with the diameter of the interchangeable collets, measured in millimeters.

Er collet sizes

Our ER collects come in 5 different sizes:

• The ER16 Collet –> with dimensions of 17 x h.28 mm; available in diameters ranging from 3 mm to 10 mm
• The ER20 Collet –> with dimensions of  21 x h.31 mm; available in diameters ranging from 6 mm to 14 mm
• The ER25 Collet –> with dimensions of 26 x h.34 mm; available in diameters ranging from 6 mm to 20 mm
• The ER32 Collet –> with dimensions of 33 x h.40 mm; available in diameters ranging from 3 mm to 20 mm
• The ER40 Collet –> with dimensions of 41 x h.46 mm; available in diameters ranging from 3 mm to 30 mm

ER Collet diameters

The ER Collet diameter refers to the diameter of the tool shank (tool-shank diameter) which the collet is designed to accommodate, which may vary from 3 mm up to 30 mm.
This is the diameter of the diamond tool that you can use (tool shank diameter)

ER collet features

• Made with hardened steel ground both internally and externally to guarantee greater precision
• Beveled corners to allow superior clamping of the collet and longer durations of the shanks and tools
• Tolerance as per DIN6499B to guarantee greater precision, a superior clamp and longer duration of the collet itself. The concentricity of the ultra-precise collet ER – DIN 6499/B is less than 0.005 mm.
• Each ER collet is available with the darkside treatment, a special corrosion-proof heat treatment at gives the collet a characteristic black color.
  Darkside collets are therefore more rust resistant and have a longer life (“darkside” tools subjected to more than 400 hours of exposure to saline testing do not rust and for this reason, they are called: Rustproof. We also offer a standard treatment
• A fantastic Quality/Price ratio

Stone fabricators often use tools with a 6 mm or 10 mm cylindrical shank, therefore 6 mm and 10 mm diameter ER collets are those most commonly used. 

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