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March 13, 2025 · The Bloomfield Team

How to Get More From Your Existing CNC Equipment

A new CNC vertical machining center costs $150,000 to $350,000 depending on size and capability. A horizontal machining center runs $300,000 to $700,000. Five-axis machines start at $400,000 and climb from there. Before writing that check, every manufacturer should answer one question: are you getting everything possible from the machines already on the floor?

Most shops are not. The average CNC machine in a job shop environment runs at 35% to 50% productive cutting time, meaning the spindle is actively removing material for less than half of available hours. The remaining time goes to setup, tool changes, waiting for material, waiting for instructions, inspection, and idle periods between jobs. Each of those categories represents recoverable capacity.

Optimize Tooling and Speeds

Tooling manufacturers invest heavily in R&D on insert geometries, coatings, and substrate materials. The cutting parameters that came with your tooling five years ago are conservative by today's standards. Sandvik, Kennametal, Iscar, and Walter all publish updated cutting data recommendations, and most provide free access to online calculators that optimize feeds and speeds for specific material and tool combinations.

A shop running carbide inserts at the feeds and speeds recommended in 2018 is likely leaving 15% to 30% of potential metal removal rate on the table. Modern high-feed milling strategies, trochoidal toolpaths, and optimized chip load calculations can reduce cycle times by 20% to 40% on many operations without any change in machine hardware.

The investment is time, not money. Have your programmer or setup technician spend a day with a tooling representative reviewing the top 10 parts by volume. Optimize the cutting parameters for each. The cycle time savings compound across every run of those parts for the life of the program.

Reduce Setup Time Systematically

Setup time is the single largest non-cutting time category on most CNC machines. A shop running 4 to 6 setups per day per machine at an average of 90 minutes per setup loses 6 to 9 hours of cutting time daily. Reducing average setup to 60 minutes recovers 2 to 3 hours per machine per day.

Three approaches work. First, standardize tooling kits for common part families so tools are preset and ready before the previous job finishes. Second, create detailed setup documentation with photos, offset values, and operator notes from previous successful runs so each setup follows a proven procedure rather than a problem-solving exercise. Third, invest in quick-change workholding systems for machines that run high-frequency changeovers. A Jergens Ball Lock or Schunk Vero-S system can reduce fixture change time from 30 minutes to 5 minutes.

Improve Scheduling Sequence

The order in which jobs run on a machine affects total productive time. Running three aluminum jobs back-to-back on a VMC requires one coolant and tooling configuration. Alternating between aluminum, stainless, and titanium jobs requires three different configurations, tripling the setup time for the same three jobs.

Scheduling similar parts consecutively, grouped by material, fixture type, or tooling requirements, reduces the number of full changeovers and increases the ratio of cutting time to total time. This requires visibility into upcoming jobs and the discipline to batch-schedule rather than running jobs in the order they arrived. The shops that schedule by gut feel lose more time here than they realize.

Run Lights-Out Where Possible

Unattended machining during off-hours is the most direct way to increase output from existing equipment without adding labor. A machine that runs a 45-minute cycle on a part with 50 pieces in the batch can produce 10 to 12 parts overnight with a bar feeder or pallet system, adding 8 hours of productive cutting without a single additional operator hour.

Lights-out operation requires reliable tooling (monitored tool life, automatic breakage detection), adequate chip management (conveyor or auger systems that prevent chip buildup), and coolant volume sufficient for extended unattended runs. Most modern CNC machines from Haas, Mazak, and DMG MORI have the monitoring capabilities built in. The investment is in the peripheral systems: bar feeders ($15,000 to $40,000), pallet changers ($20,000 to $60,000), and tool breakage detection ($2,000 to $5,000).

The payback on these investments is typically 4 to 8 months when the recovered hours are filled with revenue-generating work.

Implement Basic Machine Monitoring

You cannot improve what you do not measure. Basic machine monitoring that tracks spindle-on time, idle time, and alarm conditions provides the data foundation for every improvement described above. Modern CNC controllers can output this data through MTConnect or OPC-UA protocols. Third-party monitoring systems from MachineMetrics, Memex, or Datanomix connect to the controller and provide dashboards showing real-time and historical utilization by machine.

The cost of basic monitoring runs $100 to $300 per machine per month for cloud-based systems. The data they produce reveals exactly where time goes on each machine, which makes improvement efforts targeted rather than speculative. For more on what this data reveals, see why your machine utilization numbers are misleading.

Maintain the Machines You Have

A CNC machine that has not had a ballbar check in three years, that runs on coolant concentrate measured by smell rather than refractometer, that has way covers held together with shop rags, is not producing parts at its rated capability. Geometric accuracy degrades gradually. Thermal drift increases. Surface finish deteriorates. The operator compensates by running slower, taking lighter cuts, and making more inspection stops.

A thorough maintenance program, starting with the manufacturer's recommended schedule and adjusted based on your operating conditions, keeps existing machines producing at their rated performance for 15 to 20 years. The cost of preventive maintenance is a fraction of the production capacity it preserves.

The capacity to grow your shop already sits on the floor. The machines you own are capable of more than they are currently producing. The work is measuring where the time goes, attacking the largest losses systematically, and building the systems that connect floor data to scheduling and quoting decisions. No capital required. The return starts with the data.