Starting a CNC press brake and adjusting it correctly are fundamental skills for achieving precise and efficient sheet metal bending. This guide will walk you through the startup process, travel adjustment, die selection, manual axis adjustment for angle discrepancies, size adjustment, and safety precautions necessary for effective operation.
Starting the Machine
Powering Up
1. Connect the Power Supply: Ensure the press brake is connected to a suitable power source.
2. Turn on the Key Switch: Activate the key switch on the control panel.
3. Press the Oil Pump Start Button: This will activate the oil pump, and you should hear it running. However, the machine itself will not move yet.
Travel Adjustment
Importance of Travel Adjustment
Before using the press brake, it is crucial to adjust the travel. Running a trial bend is essential to ensure the settings are correct and to avoid any potential damage to the machine or the workpiece.
Selecting the Die Slot for the Lower Mold
General Rule for Slot Width
The slot width should generally be eight times the thickness of the sheet metal. For instance, when bending a 4mm sheet, a 32mm slot should be used.
Back Gauge Adjustment
Methods of Adjustment
The back gauge typically features both electric rapid adjustment and manual fine-tuning options. The adjustment method is similar to that of a guillotine shear, allowing precise control over the positioning of the material.
Manual Axis Adjustment for Large CNC Press Brake Angle Deviations
Steps for Manual Axis Adjustment
1. Access the Mold Management Interface: On the CNC press brake, enter the mold management screen and select the mold number you need to adjust.
2. Adjust X and Y Axes: Navigate to the manual axis adjustment screen and modify the X and Y axis values to reposition the mold correctly.
3. Adjust the R Axis: Modify the R axis value to achieve the desired bending angle.
4. Verify Adjustments: Confirm that the mold position and bending angle are correct. If necessary, perform further adjustments.
Precautions During Manual Axis Adjustment
- Ensure the CNC press brake is idle to prevent accidents.
- Use a thin material for trial bends to check if the R axis adjustment is correct before proceeding with the main bending task.
- Save the adjusted parameters promptly for future use.
- If unsure about manual adjustments or if the angle deviation is significant, seek assistance from professional technicians to ensure proper bending results and safety.
Size Adjustment for the Press Brake
Fixed Step Difference Mold
Fixed step difference molds have a constant dual bend difference dimension.
Adjustable Step Difference Mold
Adjustable step difference molds consist of an upper and lower mold. The alignment of the centerlines of the molds and gap adjustment are crucial. Here’s how to proceed:
1. Align Mold Centers: Adjust the gap by aligning the centers of the upper and lower molds.
2. Determine Back Gauge Position and Process Flow: Set the back gauge position and follow the procedure to adjust the switch.
3. Pressure Test the Workpiece: Place the workpiece in the center of the hydraulic press brake’s table for pressure testing.
4. Install the Upper Mold: Install the upper mold like a standard press brake mold, ensuring the mold core faces the operator.
5. Install the Lower Mold: Position the mold core inside the press brake.
Back Gauge Adjustment
The back gauge typically has electric rapid adjustment and manual fine-tuning capabilities, similar to a guillotine shear.
Bending Operation
Procedure
- Press the Foot Pedal: Depress the foot pedal to start the bending process.
- Release the Pedal to Stop: Let go of the pedal to stop the operation.
- Continuous Operation: For continuous bending, keep pressing the pedal.
Safety Precautions
- Insert Shims and Lock Screws: After inserting shims, lock the screws and use calipers to measure the distance between the mold seat and mold core at different points to ensure uniformity.
- Ensure Consistency: Verify that all gap dimensions are consistent to maintain bending precision.
Conclusion
Starting and adjusting a CNC press brake correctly is essential for achieving accurate and efficient sheet metal bending. This guide provides a step-by-step approach to powering up the machine, adjusting travel, selecting the appropriate die slot, adjusting the back gauge, and making manual axis adjustments for angle discrepancies. Following these guidelines, along with observing the necessary safety precautions, will ensure optimal performance and safety during bending operations.
Starting the Machine
Powering Up
1. Connect the Power Supply: Ensure the press brake is connected to a suitable power source.
2. Turn on the Key Switch: Activate the key switch on the control panel.
3. Press the Oil Pump Start Button: This will activate the oil pump, and you should hear it running. However, the machine itself will not move yet.
Travel Adjustment
Importance of Travel Adjustment
Before using the press brake, it is crucial to adjust the travel. Running a trial bend is essential to ensure the settings are correct and to avoid any potential damage to the machine or the workpiece.
Selecting the Die Slot for the Lower Mold
General Rule for Slot Width
The slot width should generally be eight times the thickness of the sheet metal. For instance, when bending a 4mm sheet, a 32mm slot should be used.
Back Gauge Adjustment
Methods of Adjustment
The back gauge typically features both electric rapid adjustment and manual fine-tuning options. The adjustment method is similar to that of a guillotine shear, allowing precise control over the positioning of the material.
Manual Axis Adjustment for Large CNC Press Brake Angle Deviations
Steps for Manual Axis Adjustment
1. Access the Mold Management Interface: On the CNC press brake, enter the mold management screen and select the mold number you need to adjust.
2. Adjust X and Y Axes: Navigate to the manual axis adjustment screen and modify the X and Y axis values to reposition the mold correctly.
3. Adjust the R Axis: Modify the R axis value to achieve the desired bending angle.
4. Verify Adjustments: Confirm that the mold position and bending angle are correct. If necessary, perform further adjustments.
Precautions During Manual Axis Adjustment
- Ensure the CNC press brake is idle to prevent accidents.
- Use a thin material for trial bends to check if the R axis adjustment is correct before proceeding with the main bending task.
- Save the adjusted parameters promptly for future use.
- If unsure about manual adjustments or if the angle deviation is significant, seek assistance from professional technicians to ensure proper bending results and safety.
Size Adjustment for the Press Brake
Fixed Step Difference Mold
Fixed step difference molds have a constant dual bend difference dimension.
Adjustable Step Difference Mold
Adjustable step difference molds consist of an upper and lower mold. The alignment of the centerlines of the molds and gap adjustment are crucial. Here’s how to proceed:
1. Align Mold Centers: Adjust the gap by aligning the centers of the upper and lower molds.
2. Determine Back Gauge Position and Process Flow: Set the back gauge position and follow the procedure to adjust the switch.
3. Pressure Test the Workpiece: Place the workpiece in the center of the hydraulic press brake’s table for pressure testing.
4. Install the Upper Mold: Install the upper mold like a standard press brake mold, ensuring the mold core faces the operator.
5. Install the Lower Mold: Position the mold core inside the press brake.
Back Gauge Adjustment
The back gauge typically has electric rapid adjustment and manual fine-tuning capabilities, similar to a guillotine shear.
Bending Operation
Procedure
- Press the Foot Pedal: Depress the foot pedal to start the bending process.
- Release the Pedal to Stop: Let go of the pedal to stop the operation.
- Continuous Operation: For continuous bending, keep pressing the pedal.
Safety Precautions
- Insert Shims and Lock Screws: After inserting shims, lock the screws and use calipers to measure the distance between the mold seat and mold core at different points to ensure uniformity.
- Ensure Consistency: Verify that all gap dimensions are consistent to maintain bending precision.
Conclusion
Starting and adjusting a CNC press brake correctly is essential for achieving accurate and efficient sheet metal bending. This guide provides a step-by-step approach to powering up the machine, adjusting travel, selecting the appropriate die slot, adjusting the back gauge, and making manual axis adjustments for angle discrepancies. Following these guidelines, along with observing the necessary safety precautions, will ensure optimal performance and safety during bending operations.
