Is conformal coating a good SOP for general purposes?

Recently I've been working on a power supply for an RC car. I am considering using this conformal coating on it:

I do not anticipate much moisture exposure aside from humidity but I'd hate to see that hard work corrode and I'd like to protect against short circuits too.

In general is it a good practice to seal a board with this conformal coating or another type of coating?

Also, I would like to brush it on but the datasheet says:

422C can be applied by brush for rework or touch-ups.
Thinning is not required for most brush applications.
Desired coating thickness can be achieved in a single
application. Applied coating can be cured immediately.

Otherwise it looks like spraying or dipping are preferred for the primary application.
I'm not set up to spray where I normally do this work and I'm concerned about gumming up buttons and such by dipping. To that point is there a similar conformal coating that can be brushed on? I have a heat gun on my bench so I can cure it or I can get a UV solution if need be.

I have used spray on conformal coating many times for boards in moist dirty environments.

The only caution in use is to make sure heat dissipation doesn't become a problem.

I’ve meant to use that, or another type that is similar.

It is fashionable and defensible, I just never get around to it.

Meanwhile it’s OK as nothing I have lasts so long that it would make a difference.

I avoid wet grass and rain &c.

Do also mind your connectors and pushbuttons if there are on your board.

a7

Have you seen the car?

I would love it to last indefinitely. and it screams to go outside.

I think I'll try brushing it on lightly and hanging it to dry, avoiding the connectors and buttons as you said.

For small boards brushing is fine.

The most important step is to clean, clean, clean before coating.

I use alcohol and then blot it with a paper towel. Unless you spray with alcohol and let the foreign material flow off, the blotting is needed. Usually several cycles makes it clean enough to overcoat.

As for needing a conformal coat. Any electronics kept inside can forgo coating. A PC motherboard is not coated, you TV is not coated etc.

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