More and more machine shops are moving to unattended or lights out machining to stay competitive. Having more production hours means higher output and additional revenue. At the Top Shops Conference, we learned that the top 25 percent of machine shops are running 14 hours a day, while the bottom 25 percent are only running 8 hours a day. On average, profit margins in machine shops running lights out were 3 percent higher than those who were not.
Benefits of Lights Out Machining
Increased profits and the reduction in labor costs are not the only benefits of running lights out. A shop can increase its capability and machine utilization without having to add new machinery. Because the machines run for extended periods during lights out, this allows the shop to increase productivity and take on additional jobs.
Running lights out also allows a shop to balance their jobs by running short or operator intensive jobs during manned shifts and running the longer jobs that need no or minimal intervention during lights out. This is also the case for parts that require secondary finishing operations. For parts that require longer secondary finishing passes, they can run during lights out operations.
7 Tips for Lights Out Machining Success
Implementing lights out does come with its challenges. It is crucial to understand and assess the risks involved and create a plan for your shop to be successful.
1. Run your proven jobs
Only run mature jobs that have consistently been running during manned hours and start with your noncritical jobs. Avoid jobs with difficult coolant aiming and never run new code during lights out.
2. Upgrade to the right equipment
Bar feeders, chip conveyors, and parts collectors are integral parts of a successful lights out operation. Bar feeders must be able to hold enough material for the full run. Chip conveyors are needed to prevent chips from interfering with parts collection. Part collectors avoid damage caused by parts falling on top of other parts and ensure that in the morning, the completed pieces are immediately ready for secondary operations or packaging. When investing in new machines, choose machines that are easily adaptable to lights out production.
3. Invest in monitoring and protection
4. Use manned hours wisely
Use manned hours for shorter jobs requiring changeovers. Perform quality checks, measurements, and inspections, which didn’t occur overnight. Use the daytime to set up for unmanned hours and invest in simple and repeatable quick change setups so operators are not rushed through the setup process.
5. Perform preventative maintenance
Keep a log for every machine that includes the necessary preventative maintenance tasks and encourage operators to note any issues or malfunctions they encounter. Regularly inspect machines, fix any issues, and keep tools sharp. Designate a person for each machine to take responsibility for the machine maintenance and address any issues noted in the log.
6. Coolant management
Closely manage coolant and lubrication systems. Best practices for your coolant management include checking and cleaning filters, tracking concentration levels, looking for any signs of bacterial growth, and monitoring pH balance daily.
7. Apply automation
In machine shops, automation tools and robots can load materials, unload, wash, dry, and package parts, or even perform quality inspections using vision systems. Automation allows machines to continue to run during lights out to optimize production. Additionally, automation takes away mundane, repetitive tasks from the operators, which enables them to focus their time on critical jobs during manned hours.
Running lights out can increase a shop’s productivity and profit, but with every reward, there is risk. Use these seven tips to set your shop up to be successful with lights our operations.