Citizen Machinery UK unveiled its third-generation Cincom L20-LFV series of sliding-head lathes at their two-day Open House event in Bushey on April 8-9. These lathes, designed for machining parts from bars up to 20mm in diameter (or 25mm optionally), come with significant upgrades and enhanced features.
The Cincom L20-LFV series is now available in five variants: VIII, IX, X, XII, and XIIB5. These models remain the top choice for manufacturers and include platen tooling, front and rear toolposts, and driven and static positions on the top three models. The upgraded versions also feature additional Y-axis movement for the sub spindle.
The lathes support simultaneous five-axis control, which allows for complex machining operations. The two highest models also offer a B-axis toolpost with an optional automatic tool changer (ATC) that can hold tools up to 30mm in diameter. These lathes are equipped with a 2.2kW motor, capable of rotating cutters at speeds up to 12,000 revolutions per minute. This setup allows for efficient metal removal even with small diameter mills, and the addition of programmable B-axis motion brings the total number of CNC axes to seven.
Innovative B-Axis ATC for Versatile Machining
Citizen Machinery was the first to introduce a B-axis ATC on a sliding-head lathe, enhancing its versatility for tasks like angled-cross working or end-facing. The ATC can hold up to 12 tools in the magazine, with an additional tool fixed in the upper position of the live tool unit. This feature supports a wide range of operations, including drilling, slitting, hobbing, and multi-axis milling at various angles.
Switchable Modes for Flexible Production
Another noteworthy feature is the machine’s ability to easily switch between Swiss-type and non-guide bush turning. This change reduces bar wastage and is ideal for manufacturing shorter components, particularly those requiring tight tolerances and precise geometry. Removing the guide bush also eliminates the need for tightly controlled stock material diameters.
Advanced Features for Higher Efficiency
All versions of the Cincom L20-LFV include Citizen’s programmable LFV function, which is integrated into the Mitsubishi Windows-based control system. The system, equipped with a 15-inch touchscreen for ease of use, offers three LFV modes of operation. These modes synchronize the X and Z servo axes with spindle rotation to break up long, stringy swarf into smaller, manageable chips. This is especially effective when machining malleable materials, leading to improved productivity, reduced tool wear, and a better surface finish.
The lathe’s gang tool post now holds up to six turning tools, providing greater flexibility. A total of up to 45 tools can be mounted in the machining area. Citizen’s ‘CIToolingSystem’ further speeds up tool exchanges and enhances repeatability, with positioning accuracy within ±2 microns.
The lathe’s design improvements include better access to the machining area, with a fully openable front door and an additional rear door. The layout has been optimized for compactness, and the coolant nozzles are arranged to improve efficiency during setup. The sub spindle’s capability has been upgraded to 3.7kW with a speed of 10,000 revolutions per minute.
Eco-Friendly and Energy-Efficient Features
Citizen’s Eco II suite of energy-saving features comes standard with the lathes, promoting environmentally-friendly manufacturing practices. The machines include functions to reduce power consumption, compressed air usage, and CO2 emissions. For example, an idling stop function puts the machine in standby mode when not actively running, while an intermittent air blow feature reduces compressed air usage by about 60%.
The Eco Monitor, displayed on the touchscreen, allows operators to track power consumption in real-time, ensuring the lathe operates at peak efficiency. Additionally, the machines are IoT-ready and can be connected to Citizen’s ‘alkapplysolution’ software. This software helps with NC program management and machine operation monitoring via a simple LAN connection.
Software for Enhanced Production Efficiency
Citizen also demonstrated its ‘alkartlive 2’ software, which visualizes machine downtime and aggregates data for predictive maintenance planning. The software uses color-coded indicators to show machine status, production results, and alarm history, providing a clear overview of factory operations.
The event also featured the automated Miyano BNA-42SY5 lathe, which now includes LFV chip-breaking capabilities. This machine was showcased live to demonstrate its potential for unattended machining.
Finally, Citizen introduced its ‘Alkart Wizard 2025’ CNC lathe programming software, which now includes a ‘CAD/CAM Toolpath Import’ function. This software provides step-by-step guidance, a user-friendly interface, and a library of machining processes, making it easier for operators to program complex lathe operations.
At the event, Citizen Machinery showcased its commitment to technological advancement, energy efficiency, and versatile manufacturing solutions. The updated Cincom L20-LFV series reflects the company’s focus on improving productivity while minimizing environmental impact.
