Trim paint and hole sealant

[Billysurf]

I have removed the trim around the bus to repaint and cover up some rust marks under the old nails.  I've painted the new stainless steel nails white and are replacing all the old rusted ones.

2 questions

1) Should I prime and/or clear coat finish after painting (see spray paint below)?
2) Should I fill the nail holes (and other holes under the trim) with something to prevent water etc. from getting in? 

[daddysgirl]

Personally, I would spray Permatex rust remover (turns any rust black and prevents it from returning) on anything that is rusted...after you clean it as much as possible with Navy Jelly but before any paint.
I'm assuming the trim has the small plastic bolt separators behind the black gasket? You might need some threadserts if you need any of those holes behind the trim.
The first picture is the bottom of the radiator screen and side engine access. Those holes are in the rivets. Take a pipe cleaner and see if those go through. I replace the rivets that have holes, but that is just me.

If your asking about painting the trim only (although my opinion would be the same anyway) do yourself a favor and invest in a spray paint system that runs off a compressor. It will save you much time. Or, look at the automotive wraps the racing industry is using now.

Anyhoo...strip...sand...repair...prime...paint...3-5 coats of clear coat is a good starting point.

[Oonrahnjay]

...  I replace the rivets that have holes, but that is just me. ...

     Nope, not just you.  Unless a "pop rivet" is specified as being "sealed" or "waterproof", it will leak water through the central hole in the pop rivet.  You'd think that the mandrel in the rivet would seal it as it's being tightened up, but the deforming or swelling process at the back of the rivet as it's being set means that there are voids opening as the rivet is set.  You have to consider any non-sealed pop rivet used on external panels as being likely to leak water.

[daddysgirl]

     Nope, not just you.  Unless a "pop rivet" is specified as being "sealed" or "waterproof", it will leak water through the central hole in the pop rivet.  You'd think that the mandrel in the rivet would seal it as it's being tightened up, but the deforming or swelling process at the back of the rivet as it's being set means that there are voids opening as the rivet is set.  You have to consider any non-sealed pop rivet used on external panels as being likely to leak water.

Thank you
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