Newbie here,
2004 Sprinter van, long and tall 307K miles.
I tried to keep up with rust over the years with rattle can SprayMax 2k primer, rattle can base and SprayMax 2k clear. I would have had perforations if I didn't do that. Right now rust is not terrible, OEM paint is some kind of water borne, very thin and the body is not galvanized. Some of you might know that Sprinters are notorious for rust.

I am going to do a complete repaint this time, from gutter down ( roof go repainted a few years ago, still ok). I got AirGunsa anesta iwata gun for primer and Tekna ProLite for base and clear.

I used paint and rust remover disc on small rust bubbles. Treated small area with bare metal with FastEtch (zinc phosphate). My plan is to sand the van with 220, glaze putty the areas I stripped to bare metal, Epoxy Primer, base and clear.
I want to make sure that those tiny orange spots don't come back.

Epoxy Primer a good solution for my problem?

Some of the pinholes that orange/rust is coming out are so tiny, probably doesnt't make sense to strip it all to metal.
Thank you for your thoughts!!!

are those pin holes from something spot welded to the back side?
Jay D.

No welding,
OEM paint is very thin, any tiny rock chip results in an orange spot in a few months and then a small bubble.
Sometimes it doesn't even take a rock chip...

The bigger spots by the wheel are areas I sanded before but not finished.

Removed small orange spots and tiny bubbles on one side and treated with FastEtch.

So I read up so more on this problem and had already read about it years ago when we were considering buying one of these for pickup/delivery. I didn't like what i was seeing back then and just ended up with a box truck that never had problems like this....
So my question to you is....do you think most of these pit/rust spots are coming from the inside out or going from the outside/in???? If they were coming from the inside heading out I would think that this spot idea is not a good approach. I mean you'd HAVE to go to bare metal everywhere just to make sure you got everything. Now, if it's more like the rail dust effect where particles of stuff are embedding themselves in the paint and THEN doing this rust penetration you would probably be okay.....

DarrelK wrote:So I read up so more on this problem and had already read about it years ago when we were considering buying one of these for pickup/delivery. I didn't like what i was seeing back then and just ended up with a box truck that never had problems like this....
So my question to you is....do you think most of these pit/rust spots are coming from the inside out or going from the outside/in???? If they were coming from the inside heading out I would think that this spot idea is not a good approach. I mean you'd HAVE to go to bare metal everywhere just to make sure you got everything. Now, if it's more like the rail dust effect where particles of stuff are embedding themselves in the paint and THEN doing this rust penetration you would probably be okay.....

How do I know for sure whether it 's coming from inside or outside?
Stripping the entire van this size to bare metal is a huge endeavor... I would want to avid that if I can.

With spots like this I can usually see how they are forming by carefully sanding a few test spots. I check off and on with a magnifying glass as I sand. Small spots that are forming on the outside sand completely off with little to no "breakthrough" of the metal. Rail dust (embedded steel shards) is like that. You can even see those shards driven into the paint and they sand "off." Spots that are forming from the inside is more like you start sanding the rust and boom! it pulls open the hole through the panel.
The only reason I am even bringing this up is the same old story of how expensive a "do over" is if you are wrong. Paint and labor are just soooo expensive...

When I start sanding some tiny orange spots, I find that area under paint is a little bigger, maybe by 1/8" around, but most of it sands off clear and leaves a tiny pit in the middle, sometimes even the center spot sands off.
In some areas I see that "orange" formed right along a scratch (thin paint).
The areas I repainted with rattle cans (SprayMax 2K Epoxy, base and SprayMax 2K clear) about 8 years ago seem to stay "orange spot" free, will look again today to confirm.

Thank you

what does the inside panel look like where you have the rust holes?
Jay D.