Manufacturing Processes
and Costs Comparison
Having roots in manufacturing, Electronic Enclosures, Inc. (EEi) knows the flexibility and limitations of each material and process. A critical step in planning and developing an optimal rack mount chassis systems includes determining what is most appropriate for both materials and process for your application and market. This may include more than one process with the possible intent to add greater perceived value or product/market differentiation. Your projected production ramp-up or level, tooling budget (if any) and target cost will begin to define or limit your choices.
For instance, the process of sheet metal rack mount chassis will be governed by either a significant tooling budget, or no budget, and production levels. If production is 10,000/year or more with significant tooling budgets, then stamping is appropriate. Conversely, if production is a few to 100s/month with little of no tooling budget then sheet metal fabrication is the way to go.
When designing for fabrication, features vs. tooling budget may result in a conflict that needs resolution. With limited or no tooling budget, many features may be possible but will increase your production cost. There are other alternatives.
Knowledge of machinery, available tooling, programming methods, setups, capabilities, etc., makes a difference as it defines the design rules and design limitations and ultimately impacting your reoccurring production costs. EEi can help with alternatives to reducing production cost. Designing to each processes’ strengths is key to reducing manufacturing costs, time-to-market and reducing production costs.
Higher production and angled SFP ports made die casting a perfect choice for its minimal secondary operations, natural EMI shielding and low part cost.
A custom extrusion provides a unique front panel appearance, part of a family look.
Injection molding is not always the most appropriate choice for plastic enclosures. With the proper concept and execution, pressure forming may provide similar feature detail and definition vs. injection molding. Structural foam, gas-assist injection and reaction injection molding (RIM) plastics may also add unique features where sheet metal may not.
A pressure formed front panel provides a unique appearance – otherwise not possible in sheet metal for this low volume rack mount system.
Labor is frequently the driver of increased production costs. Knowing how to design out and decrease laborious secondary operations is key to cost savings.
The design rules change from fabrication to stamping and from injection molding to RIM or pressure forming. In-depth knowledge of materials, tooling design and production methods all play a part in making optimal material, process and design choices. The correct choices save costs.
| Process | Pros | Cons | Volume | Tooling | Part |
|---|---|---|---|---|---|
| Sheet Metal Fabrication | Design flexibility for regular shapes Small to large parts No or minimal tooling EMI containment |
Increased labor Secondary process for hardware Secondary processes (plating/painting) |
L – M | 0 – $ | $$$ |
| Sheet Metal Stamping | Design flexibility for regular shapes Increased structural design shapes Thinner material thickness than fabrication EMI containment |
Tooling costs Tooling production time Tooling modifications Secondary process for hardware Secondary processes (plating/painting) |
M – H | $$ – $$$ | $ – $$ |
| Injection Molding | Flexibility for design geometry Uniform wall thickness Large selection of materials, colors and properties |
Tooling costs Tooling production time Tooling modifications Secondary process for EMI containment |
M – H | $$ – $$$ | $ |
| Reaction Injection Molding (RIM) | Flexibility for design geometry Thick and thin wall thicknesses |
Increased labor Secondary processes (EMI & painting) |
L – M | $$ | $$ |
| Pressure Forming | Mid to large part size Somewhat flexible part geometry |
Increased labor Secondary component assembly Secondary processes (EMI/plating/painting) |
L – M | $$-$$$ | $$-$$$ |
| Extrusion | Some design flexibility Small to medium part size EMI containment |
Limited material options Secondary operations (machining & surface preparation if unpainted) Secondary processes (plating/painting) |
L – M | $$ | $$ |
| Die Casting | Flexibility in design geometry Increased structural strength EMI containment |
Limited material options Secondary operations (trim/threading/machining) Secondary processes (plating/painting) |
M – H | $$$ | $ – $$ |
Additional Considerations
- Market
- Customer perception
- Production levels
- Products’ physical size
- Environment
- Industry compliance
- Tooling budget
- Reoccurring costs
- Material selection
- Tooling production affecting time-to-market
- Tooling material options
- Tooling design
- Part design geometry
- Coatings for EMC compliance
- Secondary processes
- Plating
- Painting
- Decorating (silk-screen, labeling, etc.)