Coating a PCA can happen in one of a few ways, at the most basic level coatings are applied by hand, usually with a spray but it can be applied with a brush or a hand dipping process. We will briefly describe the process for hand coating, machine dip coating and machine spray coating below to give you an understanding of the pro's and con's of each method.
When you are only producing a limited number of boards it can be an uneccessary cost to invest in coating machinery. If coating isn't a daily task, or if it's limited to a handful of boards it's most cost effective to hand coat the boards. If you're just waterproofing a single board then you'll probably be applying the coating with an aerosol or a brush, if you have a regular need to coat a few boards then a spray coating set-up will come in handy. If hand brushing then an extracted inspection booth should be used with a long wave black light to help the coating process.
If you produce a regular output of boards that need coating we recommend that you choose an automated solution for coating, not only will you find that the process becomes far more repeatable but you'll reduce exposure to the coating materials. At the most basic level of machine items are vertically dipped into the coating solution for a set time period. Depending on the coating they may also be cured with UV or infrared light.
On some boards you won't want to coat all of the components, while there are ways to selectively coat boards with hand and dip methods, they're not as precise or quick as an automated spray coating machine can achieve. A preprogrammed pattern of movements allow boards to be coated in selective ways that other processes cannot match, emulating a hand brush process but with the machine consistency. Spray coating allows for the maximum control over where you want the coating to be applied.