Pagnoni ER Mini Collet Chucks with SK Tape

Available Sizes and Part Numbers

Purpose and Application

Pagnoni ER Mini SK series collet chucks are manufactured in Italy for use on CNC milling machines and machining centers with SK spindles according to ISO 7388-1 (DIN 69871). The primary technological purpose of this series is operation under strict geometric constraints, machining of hard-to-reach surfaces, deep slots, matrices, molds, and complex structural parts where standard ER nuts create contour interference.

Design and Features

The main design feature of ER Mini chucks is the use of a reduced-size clamping nut (Mini nut). The outer diameter of the nut is only 16 mm for ER 11 Mini, 22 mm for ER 16 Mini, 28 mm for ER 20 Mini, and 35 mm for ER 25 Mini. Tooling is manufactured from alloyed case-hardened steel with surface hardening to HRC 58±2 (case depth 0.4–0.5 mm). Thread cutting and chamfering are executed after heat treatment. Chuck bodies undergo bluing, and mounting tapers are precision ground to accuracy < AT3 (DIN 7187 / DIN 2080). Chucks undergo 100% outgoing quality control and are balanced to class G 6.3 at 12,000 rpm. Supplied with GHRMN series nuts and an internal length adjustment screw.

Compatibility

Chucks are designed for machine spindles with SK 30, SK 40, and SK 50 tapers (ISO 7388-1 / DIN 69871). Compatible with ER system collets of the corresponding size: ER 11 Mini, ER 16 Mini, ER 20 Mini, and ER 25 Mini according to ISO 15488 B (DIN 6499 B) standards. Spindle retention is achieved via pull studs conforming to DIN 69872 (e.g., Pagnoni 930TIR01, 940TIR01, 950TIR01).

Selection Parameters

Selection is based on spindle taper (SK 30, SK 40, SK 50) and ER Mini collet size:

• ER 11 Mini: shank clamping 1–7 mm, nut outer diameter D = 16 mm;
• ER 16 Mini: shank clamping 1–10 mm, nut outer diameter D = 22 mm;
• ER 20 Mini: shank clamping 1–13 mm, nut outer diameter D = 28 mm;
• ER 25 Mini: shank clamping 2–16 mm, nut outer diameter D = 35 mm.

For machining in deep cavities, extended modifications with projection H (LPR) of 100, 130, 160, and 200 mm are available.

Key Advantages

• Minimal Outer Dimension: slim clamping mini-nut (starting from 16 mm) allows operation in tight areas without collision risk between the chuck body and workpiece.
• Precision Taper Accuracy < AT3: high-quality grinding ensures reliable spindle contact and high machining precision.
• High Wear Resistance: case-hardened steel with HRC 58±2 hardness prevents clamping surface deformation.
• 100% Quality Control: individual inspection of each production unit at the Pagnoni factory in Italy.
• Extended Executions: range of projections up to 200 mm expands technological capabilities for deep mold milling.