Mastering OEE in Metal Fabrication: A Guide for CNC Shops & Fabricators

In metal fabrication, your machinery is your revenue. An idle spindle on a CNC machine or a halted stamping press isn't just a quiet machine; it's a direct and immediate hit to your bottom line.

Mike, a shop floor manager, is frustrated. His most expensive 5-axis CNC machine has been down for two hours with an unassigned alarm code.

His best machinist is standing idle, a high-value part is half-finished on the table, and the downstream welding department is waiting. Every minute of downtime costs him hundreds of dollars in lost revenue and wasted labor.

The Diagnosis (The OEE Data)

A modern OEE system, connected directly to your CNC machine's PLC, provides an instant, real-time diagnosis. It tells you the second a machine goes down and, in many cases, can capture the specific alarm code that caused the stop.

The Integrated Cure (The CMMS Reflex)

In a modern shop, an alarm code is not just a blinking light; it's a trigger for a solution. This is the Fabrico workflow.

The OEE system detects the CNC alarm (the diagnosis). This event instantly and automatically creates a high-priority work order in the integrated CMMS, pre-populated with the machine ID and the specific alarm code.

This work order is sent directly to the phone of the on-duty maintenance technician, turning a multi-hour diagnostic scramble into a seconds-long, data-driven response.

The Diagnosis (The OEE Data)

Your OEE data provides the hard evidence. "Planned Stops" are your biggest source of lost time, driven by long and inconsistent job changeovers on your presses and CNC machines.

The data shows you which setups take the longest and which machines are the most difficult to get running, giving you a clear target for improvement.

The Integrated Cure (The Digital Checklist Workflow)

The solution is to standardize this complex process. Each job changeover is managed as a planned work order in the CMMS.

This work order contains a mandatory digital checklist that guides the operator or setup technician through every critical step. This can include loading the new program, setting the work offsets, verifying the tooling, and checking the first part.

This turns a chaotic, tribal-knowledge process into a standardized, repeatable one, systematically reducing your setup times.

The Diagnosis (The OEE Data)

Your OEE Quality metric shows a rising scrap rate on a specific machine as parts start to fall out of tolerance. Or, your OEE Performance metric shows a slow, gradual degradation in cycle time on a long production run.

The Integrated Cure (The Proactive Maintenance Trigger)

These are often symptoms of tool wear. The OEE data (the diagnosis) serves as a powerful trigger for proactive maintenance.

A manager can use this insight to create a work order in the CMMS to inspect and replace the cutting tool before it fails completely or produces a high-value scrapped part.

By tracking this data over time, you can even use the CMMS to build a data-driven tool management program, scheduling replacements based on actual machine runtime or part count, not just a guess.

How do you connect OEE software to a CNC machine?

Most modern CNC controllers (like Fanuc, Haas, Siemens) can be connected directly via protocols like MTConnect or through ethernet cables. A flexible OEE platform like Fabrico can pull data on machine status, cycle times, and alarm codes directly from the controller.

What is a good OEE score for a CNC machine shop?

Due to the high complexity and frequent setups in many job shops, a "good" OEE score can be lower than in other industries. However, world-class machine shops still aim for the 85% benchmark by focusing relentlessly on minimizing setup times and eliminating unplanned downtime.

Can OEE be used in a high-mix, low-volume job shop?

Absolutely. In a high-mix environment, OEE is a powerful tool for quickly identifying which jobs are the most and least profitable. It helps you understand which setups are taking too long and which parts are generating the most scrap, allowing you to price future jobs more accurately.

Maximizing the profitability of your shop means maximizing the productive time of your most expensive equipment.

An integrated OEE and CMMS platform is the essential operating system to do that. It connects the real-time diagnosis from your machines to the rapid, systematic cure from your maintenance team.

Ready to see how an integrated OEE and CMMS platform can maximize the ROI of your machinery?

Book a personalized demo of Fabrico today.