Posted on by Carl Marchese
Should Panel Builders Machine Electrical Enclosures In-House or Buy Them Pre-Machined?
For panel builders, enclosure modification is part of nearly every project. HMIs, Pushbuttons, cable glands, disconnects, ventilation, connectors, and other equipment all require holes or cutouts before a panel is complete.
The question is whether those modifications should be made in-house or supplied by the enclosure manufacturer or another outside partner.
There isn't one answer that works for every panel shop.
When In-House Machining Makes Sense
For panel builders with the right equipment and personnel, modifying enclosures internally can provide significant advantages.
It gives the shop direct control over scheduling and makes it easier to accommodate last-minute design changes. A one-off enclosure or prototype can potentially be modified immediately rather than waiting for an outside supplier.
Panel builders with CNC equipment and sufficient volume may also achieve very competitive modification costs.
In-house modification can be particularly attractive when:
- The shop already has suitable machining equipment.
- Modification is a core production capability.
- Designs change frequently.
- Quantities are small.
- Very fast turnaround is required.
- Engineering and production work closely together.
The enclosure material matters as well. Cutting and drilling steel, stainless steel, fiberglass, aluminum, and thermoplastics require different tooling, processes, and safety considerations.
When Pre-Machined Enclosures Make Sense
Outsourcing modification becomes more attractive when the same enclosure design is being produced repeatedly.
Once the machining program has been established, a supplier can potentially provide dozens or hundreds of enclosures with identical holes and cutouts.
That can free panel-shop employees to concentrate on wiring, component installation, testing, and other higher-value operations.
It can also reduce the possibility of losing an enclosure because a hole was drilled in the wrong location.
Don't Compare Enclosure Price Alone
A useful comparison is not simply the price of an empty enclosure versus a modified one.
Consider:
Empty enclosure cost + programming/setup + machining labor + tooling + handling + scrap/rework
versus:
Cost of an enclosure delivered ready for component installation.
For some panel builders, the first equation will win. For others, the second will.
A Hybrid Approach May Be Best
It doesn't have to be an all-or-nothing decision.
A panel builder might outsource repeat production while keeping prototype and emergency modifications in-house. Another might outsource complex HMI openings while drilling simple cable-gland holes internally.
The right approach depends on equipment, labor availability, volume, lead time, material, and how frequently the design changes.
If you're evaluating whether pre-machined enclosures make sense for a project, Fibox can review your drawings and modification requirements and help you compare your options.