https://missionengineering.com/dont-goop-me-bro/Fortunately, these days we have a much better choice for hostile environments with conformal coatings. Conformal coatings are commonly used now on electronics products that will be installed outside. Think traffic signals, or roof mounted solar panels. The coatings are available in several different base materials, and can be sprayed on either by machine or by hand. They can provide IPC level protection at thicknesses of only around 1000th of an inch. They are also flexible for improved reliability, relatively easy to remove to allow repairs, and often transparent for easier quality control and troubleshooting.
And therein lies the moral of this tale, if you really do want to go to the extent of protecting the PCB on your effects pedal from the hostile environment of beer spillage and maybe worse at the local dive bar, a transparent conformal coating is the way to go. Many board assembly shops will have conformal coating facilities or can send the boards on to a specialty coating service. Coating can be done with a spray head that covers an entire panel, or with a selective coating machine that dispenses the coating to specific areas. For small run, hand assembled products, you can pick up spray cans from a chemical or electronics supplier.
