150 mm 4-Jaw Independent Chuck – M33 x 3.5 mm
The 150 mm 4-jaw independent chuck with M33 x 3.5 mm threading is designed to offer maximum control and precision in clamping operations. Unlike self-centering chucks, the four individually adjustable jaws allow for precise clamping of irregular, asymmetrical, or off-center workpieces. The M33 x 3.5 mm threading ensures wide compatibility with professional and semi-professional lathes. Made from robust and resistant materials, it ensures high stability during machining, reducing vibrations and improving operational safety. Suitable for precision machining, technical turning, and professional applications, it is the reliable choice for those who need flexibility and total control over clamping.
Main Specifications
4-jaw independent chuck
Diameter 150 mm
Threading M33 x 3.5 mm
Individually adjustable jaws
Suitable for irregular and off-center workpieces
High stability and clamping precision
Robust and durable construction
Technical Specifications
| Specification |
Value |
| Type |
4-jaw independent chuck |
| Diameter |
150 mm |
| Threading |
M33 x 3.5 mm |
| Number of jaws |
4 independent |
| Use |
Clamping irregular workpieces |
| Application |
Turning / precision machining |
| Area of use |
Professional and advanced hobbyist |
Standard equipment
1 4-jaw independent chuck
Jaws included and pre-assembled
Logistics
Bernardo shipping: 5–9 working days (7 days in the South). Original spare parts available with 3–5 working days shipping. Customer support in Italian available.
Frequently Asked Questions
What is the operational difference between a 4-jaw independent chuck and a 3-jaw self-centering chuck?
In a 3-jaw self-centering chuck, the jaws move simultaneously — fast and automatic centering, suitable for workpieces with a circular, hexagonal, or multiple 3-fold symmetric cross-section. In a 4-jaw independent chuck (like this one), each jaw is adjusted separately with a key: this allows for precise clamping of square, rectangular, asymmetrical, off-center workpieces, and workpieces with irregular shapes that a 3-jaw chuck cannot center. Setup takes more time (3–5 minutes with a dial indicator) but centering precision is superior — up to 0.01 mm with a dial indicator.
Is this chuck compatible with my Bernardo lathe?
The chuck has M33 x 3.5 mm threading — compatible with lathes that use this standard attachment. Please verify the threading of your lathe before purchase. Adapters are available for lathes with ISO attachments (A1, A2). Customer support in Italian available.
How do you center an irregular workpiece with a 4-jaw chuck?
Standard procedure: 1) Roughly mount the workpiece in the 4 jaws. 2) Rotate the chuck by hand and place a dial indicator on the diameter to be centered. 3) Adjust the opposing jaws (in diametrically opposite pairs) until the dial indicator shows less than 0.02 mm of error. 4) Uniformly tighten all jaws, ensuring the workpiece does not move. With practice, 3–5 minutes for centering within 0.05 mm.
Do the jaws reverse for external clamping?
The jaws of a 4-jaw independent chuck are typically reversible — they can be removed and reassembled in the inverted position for external clamping of hollow workpieces (pipes, flanges). Please refer to the included instructions for the specific procedure for this model.
Delivery times?
Original spare parts available with 3–5 working days shipping. Customer support in Italian available.
