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Meeting Customer Requests for Precision Coating
Spray nozzle system can tilt through 360°.

In order to stay relevant in the industry, innovative equipment product lines must be considered "living" things by their manufacturers. Meaning, manufacturers must be willing to listen to customer feedback and sponsor advancements on their systems accordingly. The best equipment manufacturers do this continually — the overall goal being to create equipment that provides the best possible solutions to meet market needs.

Its Evolution
Several years ago, Specialty Coating Systems introduced the SCS Precisioncoat and its features and options have been evolving ever since. The Precisioncoat precisely sprays and dispenses 100 percent solids, solvent-based and water-based coatings, including photoresists, acrylics, adhesives, solder mask and anti-microbial coatings, to virtually any surface or substrate. In addition, alternative system applications are available; an RTV dispense platform accurately applies gasketing materials to create form-in-place gaskets and seals; A potting platform uses a multi-head setup to dispense potting materials in a controlled and repeatable manner.

Already answering the need for a system that can handle all types of conformal coating materials, the Precisioncoat has evolved to handle numerous variations of substrates and devices with its five-axes tilt and rotate functionality. Available in pneumatic or motorized versions, tilt and rotate functionality gives users precise movement along the x, y and z axes in addition to programmable tilt up to ±60° and complete 360° rotation, enabling the system to coat alongside and underneath virtually any device. This flexibility enables the system to articulate a seemingly unlimited number of angles to coat the most complex components.

Other features of the SCS Precisioncoat that have evolved over time to include an advanced proprietary vision system, which utilizes fiducial recognition for accurate programming and position compensation. Coupled with the company's automated needle calibration feature and barcode reader capabilities, the Precisioncoat ensures that each and every assembly is coated according to process specification.

Customers Ask for More
In addition to the features and options on the SCS Precisioncoat, customers were looking for help as they continually strive to run a lean and efficient operation. As a result, SCS set out to develop several features that automate certain steps in the coating process, reducing the need for human intervention and variance. This, in turn, makes the customer's coating process instantly more efficient, consistent and reliable.

Regulating Nozzle Pressures
Spraying repeatability requires precise control over material flow rate and atomization pressure. Changing atomization pressure alters the spray pattern. Historically, systems rely on the operator to set air and coating pressures, but after working with customers, SCS added the programmable atomization feature.

When air is applied through the nozzle, it essentially breaks up the material into a fine mist and directs it down to the board. Less air gives a very fine angle spray, more air widens the pattern. Well intentioned adjustments by different operators on different shifts can result in compromised coating distribution or overspray on components in keep-out areas — unacceptable results within an automated production line. Adding air pressure to the list of programmable options on the Precisioncoat removes process variation in the nozzle atomization spray level. The atomization pressure is kept in the coating program and is specific to an individual board profile. These fields are password protected, so manufacturers can choose to only make pressure changes available to shift supervisors and/or production engineers. In addition, programmable atomization pressure allows users to utilize various pressures within a single coating profile, if the coating demands of a component require such controlled variation in coating patterns.

Automated Cleaning
Due to the nature of conformal coatings, coating systems may require continual cleaning — be it in the middle of a coating run, between runs or simply at the end of a shift. The same coating properties that allow a coating to become a solid, protective shield on the receiving surface also allow it to become a solid material on the coating nozzle and/or needle, which can create uneven spray/dispense patterns if not maintained appropriately.

Fixture Cleaning
Pending the type of material being applied, cleaning of the nozzle and/or dispense needle may be required at timed intervals during the coating process. The cleaning process often consists of a solvent dip (or soak) and subsequent air purge to clean the nozzle and ready it to continue the process or begin a new board. In addition to the frequency of this cleaning, the length of time that the nozzle dwells in the solvent solution can also vary, depending on the material.

Again listening to the needs of customers, SCS added a "dip and purge" feature to the Precisioncoat's list of options. The Precisioncoat dips the spray nozzle and/or dispense needle into a cup of solvent and pushes atomizing air through the nozzle to empty the solvent and dissolved coating material into a purge cup. Once clean, the nozzle and/or needle are ready to go back to work, accurately spraying and dispensing programmed patterns. The ability to program this feature gives users control of exactly when cleaning occurs.

Maintenance Cleaning
Conventionally, routine system cleaning requires one operator to remove the coating material pot, hook up another pot that contains solvent, and purge the system manually, usually at the end of the shift/day. With the SCS Precisioncoat, an operator can push a button and a manifold valve enables the maintenance cleaning to occur without the risk of spilled coatings and solvents and unnecessary change-over time.

The manifold valve system enables the SCS Precisioncoat to use two pressure pots — one for the coating material, and one for the cleaning solvent. When maintaining the system, the solvent valve opens and pushes solvent through the coating system lines, cleaning the lines of residual coating material. A third valve then pushes air through the system to dry the lines and prepare them, again, for coating material. Cleaning the system without stopping to change out tanks not only makes the routine maintenance process more efficient, it also reduces the risk of spills, significantly reducing costly waste while improving operator safety.

Ongoing Partnering
Specialty Coating Systems is continually working with customers to understand their needs and evaluating new features for the SCS Precisioncoat. These features can be grouped into the category of coating process automation, which improves coating efficiency — reducing costs and operator errors. These features ensure a reliable, accurate spray and/or dispense pattern every time.

In terms of future development, the company is currently working with customers on several new features that are certain to continue helping manufacturers move toward their goal of streamlining manufacturing processes.

Contact: Specialty Coating Systems, Inc., 7645 Woodland Dr., Indianapolis, IN 46278 800-356-8260 or 317-244-1200 fax: 317-240-2739 Web: 

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