elmec aims to be a multifunctional hub, combining the skills of its in-house team with the collaboration of valuable external partners, which allows us to expand our operations to suit your project needs.
Painting is essential in the construction of a mechanical case for electronic devices and is among the processes we entrust to specialised collaborators with high-quality standards. This allows us to range between different types of processes, all of which are equally valid.
The main options are liquid coating and powder coating: which is best for your project? There is no single answer to this question, but a few characteristics of the two processes can help you understand which alternative is best for your specific case.
Liquid coating
Liquid painting is a process carried out manually and involves spraying liquid paint onto the surface of the product. The manual execution and the type of raw material used allow even particularly complex geometries to be evenly covered, resulting in a uniform distribution of thicknesses.
The process can be used on both metals and non-conductive materials, such as plastics. By liquid coating your electronics cases, you can also provide for metal areas free of varnish (achieved by selective masking or simply directing the jet) that are functional for the conductivity of electrical contacts.
The parts to be treated should always pass through a SURTEC pre-wash and chrome-plating stage which ensures uniform adhesion of the paint to the product. These are additional steps that entail a little extra investment, but do not nullify the cost-effectiveness and practicality of this type of processing.
Liquid painting is perfect for small and medium-sized series, has low set-up costs and does not require a minimum quantity of paint to be started. It also allows original colours to be produced, which can be easily matched to any type of project.
Powder coating
Powder coating, on the other hand, is a generally automated finishing process that involves the application of special thermosetting powder paints on metal via a mechanism that exploits electrostatic energy. Dedicated equipment can charge the metal piece to be treated with a positive charge and the paint with a negative charge.
Also in this case, it is necessary to go through a washing phase and a treatment aimed at increasing the adhesion of the paint to the surfaces. The paint thicknesses obtained tend to be greater than with liquid paint (approx. 60-100 microns) and offer more effective protection against external influences. However, powder coating does not distribute evenly on difficult shapes, such as corners or edges. Electrostatic charges tend to attract more product in those places.
Leaving conductive metal areas in this case is slightly more complex, as it requires the use of special adhesive tapes that can withstand the high temperatures of the final stage of the process (up to 200°C).
The costs and setup times for powder coating are higher than for liquid coating, making it more suitable for large series. Furthermore, there is a minimum quantity of powder coating to be purchased of around 25-50 kg. However, the parts that can be produced are numerous and run into the hundreds, making larger projects easily scalable.
Do you have doubts or questions about the two processes or are you unclear which one is the most suitable for your electronic device case? Contact our technicians and analyse the project together to find the most effective solution to your needs!
