Just like electronic equipment rack designs and accessories, the end use for your product determines the best type of metal finishing option to use for your custom electronic enclosure or rack. Finishes provide a durable coating that protects a product from its environment and function best. Does your enclosure need to be able to withstand high temperatures? Avoid corrosion? Promote electrical conductivity?
Frankly, cost and production time are less important factors. You want the best results possible! Read on to determine which metal finishing option is best for your electronic enclosure.
Metal Finishing Option: Bare Metal Finishes
There are three options: “no finish”, “grained finish” and “tumbled”.
About “No Finish/Natural”
Parts are de-burred with no additional finishing, but minor surface scratches and blemishes are to be expected. There’s no additional cost and best used for functional parts that won’t be on display.
About “Grained Finish”
Parts are de-burred, and then given a specific linear grain direction via brushing. It can only be applied to accessible flat exterior faces on machined parts and can also be digitally printed or silkscreened.
About “Tumbled Finish”
A great option for machined parts, but maximum size is 10x10x10. This process smooths and imparts non-directional finish via tumbling in abrasive medium. It can also be digitally printed or silkscreened.
Metal Finishing Option: Powder Coating
Powder coating is a dry finishing process in which free-flowing, thermoplastic or thermoset powder material, rather than a liquid suspension, is applied to a surface, melted, and then allowed to dry and harden into a protective coating. It provides a better, more durable finish than paint. It’s also highly effective in removing surface defects.
- Thicker and specialty finishes available
- Less environmental impact
- Shorter curing, processing and drying times
- Undamaged and uncontaminated powder overspray can be reclaimed and recycled for future applications (utilization rate is close to 100%)
- Range of suitable materials is limited due to the fact that it must be heated to be cured
- Difficultly producing thin coatings
- Not cost-effective for custom, small batch coating needs
- Curing and drying times increase for large, heavier parts (due to higher temperatures required)
Metal Finishing Option: Chemical Conversion Coating
Also known as Chem Film or chromate coating, this process applies chromate to a metal surface that is corrosion resistant, durable and exhibits stable electrical conductivity.
If you’re using your rack in a rugged environment, use a vendor that is MIL-DTL-5541F qualified. The standards include utilizing a process that doesn’t use toxic hexavalent chrome and has been replaced with the safer zirconium, titanium or trivalent chromium. It’s also been sufficiently tested against corrosion and proves to have reliable electrical conductivity.
- Extends the service life of parts
- Cost efficient and economical
- Doesn’t change part dimensions
- High energy demand
Metal Finishing Option: Anodizing
Anodizing is an electrochemical process that involves dipping aluminum into a bath of acid and passing an electric current through the medium. It converts the surface into a decorative, durable, corrosion-resistant oxide finish.
Anodized aluminum protects satellites from the harsh environment of space, and revolutionized the construction of computer hardware, scientific instruments and consumer products like kitchen appliances.
- Durability – creates an extremely hard surface that is more resistant to scratches
- Resistant to corrosion, heat and electricity
- Low environmental impact – non-toxic finish with no harmful by-products
- Limited color selection and its often subject to color variations
- Requires a high-grade alloy of aluminum
- Not cost effective for small quantities
Contact us today to learn more about the different types and colors of enclosures finishes that are available.