I have a very rusty trunk floor on my Olds.

No holes though.


I removed all surface rust with a wire wheel and grinder.

I then treated it with Rust Mort then rinsed it clean and immediately blew it dry, even ran a heat gun to make sure all water is removed.

Painted with Transtar DTM primer.

Next day I lightly sanded and painted with Duplicolor Spatter paint, a few days later(to make sure spatter was 100% dry) I looked at the trunk and noticed brown spots. WTF

Sanded down and found rust below the primer WTF.


Will restrip everything back to bare metal but was should I treat and paint with???


Prep??????



EPOXY? Whoes???

POR15??? paint or brush???


OR????




Whos paint should I use, need Black and Aqua????



2nd time I've done this in 5 years, getting pretty ticked off also I live in a very dry climate as well WTF???

thanks,

Fred

 

I would really like to get an answer to this as i have the same problem

 

That's interesting that the rust came back? I have had great success with por 15, but you will need to prime when it is just tacky. Or use por15 intercoat primer I also think epoxy primer would be fine ! Rust doesn't grow it needs air to oxidize I am not certain but I think the duplicolour is a latex product? Or porous at least perhaps sealing it after with a flat clear ?i am no expert just trying to help

 

There's a lot of differing opinions on rust treatment/preventatives. If you can't remove every trace of rust, with blasting, or whatever, POR-15 works well. I dont' recommend using it under paint, though. Undercarriages, floors, trunks, etc, it's a really tough coating. Only 2 issues with it. UV light makes it look chalky, and it breaks down. The other, is once it dries, it's real hard to get anything to stick to it. I bypass this by either putting a topcoat on it after a second coat, when it is still just slightly tacky, not dry, not wet. If I can't get to finish it all the way, I put a coat or 2 of primer on it, then I can sand and paint the primer, instead of the POR-15.
Underfloors and trunk I use rubberized undercoat, or even better, truck bedliner. It is smoother, tougher, and cleans up easier.
Inside of the trunk I've found that regular spatter paint isn't very tough, and doesn't hold up to getting wet. Comes right off! I've found using "Zolatone", you can simulate the look of spatter paint, but it's waterproof and tough. I've matched GM trunk colors to their different choices, but sometimes to get it exactly, I mix up 2 different mixes. TGP Global carries it.

 

x2 with above posts. IMO rust "converters" are useless, use POR-15. Also as stated, catch the POR while it is tacky & apply the next coating, in this case spatter paint. Apply first coat very lightly, let it tack off, follow w/ another light coat & tack, follow w/ finish coats to taste. IIRC I used to go through 4-8 aerosol cans in "A" Body trunk. Once spatter paint is completely dry coat it w/ matte clear, preferrably a catalyzed product. Surface will stand up strongly to abrasion or chipping & be impervious to water.