The Stovebolt Site Forums The Shop Area Paint and Body Shop Age Old Primer Question Unsolved

So I'm like all the other normal guys. I do small repairs at a time. A section of a door, a patch panel on a fender, bed side an so on. I do these over months, maybe years. Now I'm not talking about frames and brackets. Those are no sweat. Paint them with Rustoleum and use them like that. I'm talking future painted body parts that in the back of our minds we think we will do the body work and filler work and let "a Pro" paint it...or Maaco; But maybe we will try it ourselves.

We, I say we, which could be just me, don't want to screw around with buying some epoxy, mixing it, spraying it, cleaning gun with paint thinner, putting it all away and hope we don't go past the shelf life of the paint, which we may do, for a small area. I've only painted once with my gun in 2006. I don't live in a wet zone but you can't leave bare metal here either.

So here's my small patch with some bare metal and filler which is feathered out to old paint which could be lacquer or who knows what. Even though I'm not supposed to, I spray it with Rustoleum auto primer. Lightly. It's right there on the bench, you just shake it a push the button. Heaven. According to everyone it's actually hell. So when it's time to paint, is there anything yet that can be sprayed on it to seal it or will epoxy seal it after months of Arizona sun heat? I don't want Zero rust or ospho or acid etch or Kills. I just want to know if this Rustoleum will ever not outgas/react/ruin a proper coating later. If I paint a top coat of enamel, will that not react? Will the solvents/carriers in Rustoleum wait to attack me forever? People use guide coats of rattle can. Is that ALL sanded off?

I don't think I will ever stop using it, I am much to lazy and stubborn and cheap and it makes me mad that there is nothing I can do about it.
New and Old body shop guys will always say the paint is only as good as the prep, so use a good 2k primer or epoxy. These guys have all the stuff in a cabinet at work, all the materials, paint stations, cleaning stations, big dry air supply, paint booth, good guns, and experience and hate rattle cans. I don't blame them but I ain't them. There has got to be a way to protect small areas with something that will accept epoxy and then urethane top, that comes in a rattle can. If we can send a man to the moon....never mind.

My plan B is that I have calculated that paying the painter guy to sand off the light coat of Rustoleum Auto Primer will be less money and bother than buying 1 gallon of epoxy primer and 1 gal of activator every 6 mo's when the old one's go bad.

Let me have it, I can take it.

Epoxy primer left in a sealed can will last far more than 6 months, even you have used some. In fact you can expect several years!

Any aerosol primer and aerosol paint will work together nicely.... just not as good rust resistant as epoxy.

Yes you are right, I was exaggerating too much. SPI says 2 years. I'll have to consider using Eastwood's 2k "rattle can"....but it's shelf life is 48 hrs after puncturing and is $30 per 12 OZ shipped. For me, at least, that could be the answer. Lazy does cost money. But that would be the smart thing to do. Here in AZ, maybe I could just sand all the pieces I collect that have gotten surface oxidation (because I skipped the Rustoleum) and then spray them all with Eastwood epoxy 2k can. Then create another set of parts and so on. $30 a shot does sound like a lot but when the repairs are done I can gun the whole truck with Eastwood epoxy. All that I am doing could be saving me thousands. So all relative. Then either have the nerve to paint top coat myself or have it done. I will probably try it in the end. It's beginning to be almost a bucket item for me at my age.

Robert (MP&C) here uses a brush for epoxy primer for small spots. You could even use a throwaway brush, mixing just what's needed for the painting, maybe waiting till the end of the day and brush primer all the spots you've been working on at the same time. The unmixed components should last a long time (nearly as long as an unopened can).
For what it's worth, I got a couple of spray cans of 2 component epoxy ($20 each) to try that out. We'll see how it goes. Supposed to last up to 2 days after activation.

Good info Kevin, thanks. I was typing when you posted. Where did you get the 2k spray cans? I know Robert is THE guru on metal working, body and paint. Never thought of brushing, how simple, less mess, no clean up, less airborne vapors. My mind didn't go to brushing when speaking of auto painting but with spot priming, it probably lays pretty flat and will need sanding anyway before more epoxy. Maybe he also thins/reduces it?

What I got was Spray Max 2K Epoxy Primer #368 0032. One of the guys who works for me has an account at a local autobody paint place and picked them up for me at his discount. The can says that it lasts up to 4 days after activation. It has a plunger on the bottom of the can that breaks a membrane or something to mix the two components together. Says it needs to be used within 36 months of manufacture, so I've got 2 years left to use mine up.
I can't remember if Robert said he had thinned it for brushing, but his post on the garage journal forum are some good info.

SPI can be mixed and LEFT IN THE JAR FOR A WEEK... Mix a few more ounces and its good for another.
Your excuses seem weak to me...

Eastwood also carries the epoxy in spray cans. I have not used it though. I use PPG DP90. I have mixed up some for small parts or to touch up a hole I've drilled and then brushed it on. No problems there. One thing to consider, with the PPG anyway, is to cover it within the first week with primer surfacer or you get to rough it up again followed by another coat of DP90.

Dennis

My post was sort of a tongue and cheek for the "Age Old Question":
In 2017 can I paint over Rustoleum Auto Primer after months in the heat or not?
I agree, My weakness/excuses/laziness was brought out several times by moi.

I will get some two part epoxy. (Quart) Eastwood and Summit are a fair but cheaper than SPI. Same basic pros and cons. Same basic reviews. Not as much help as SPI but don't help for brush on epoxy. I will read the sheets. Gotta get into the modern era sometime. Thanks all for the info.

I dont paint over rustoleum primer except with rustoleum top coat. I just got done using the rustoleum on small parts like you said and it seemed to take forever to dry. Lat weak I took a small dash piece that was coated with rustoleum primer left to sit for 48 hours and top coated it with acrylic enamel from another company. It lifted in places and ended up glass beading it all off and starting over. This time with some good DTM summit epoxy 2 part primer, turned out killer. I am of course a do it yourself novice painter.

Thank you.

I'm not sure about the Spray Max 2K primer, but you can extend the usable life of the Spray Max 2K clear coat by keeping it in the refrigerator after you activate it. You get an extra day or two out of it.

Bartamos, like you, I always have a can of Rustoleum primer handy. Sometimes when I spray areas that I've feathered to whatever paint was on there to start, the Rustoleum 'crinkles' over the old paint but not my fresh work. I did some research on it and discovered that most rattle can paint has a chemical called Toluene in it. That chemical can react with old paint and cause the crinkling. It's a pain when it happens because then it involves sanding the primer off. And I hate to admit that I've learned the hard way (more than once!!) that when you try priming it again after sanding it off that it inevitably crinkles again.

Matt

I'll have to resand two fenders. They have light coat of rustoleum. Then only use it for brackets and such/semi gloss black stuff. I will start getting used to epoxy 2part. Goes on under or over filler. Goes on old paint if sanded first. Don't need etch or filler primer or sealer and all that. Sand the epoxy, do a final epoxy and paint top within window. SPI's "The perfect paint job" says 2K primer over epoxy before top. I say epoxy is a filler primer especially when reduced as SPI says. 2K primer over epoxy is not for adhesion, it's for filling/blocking in my opinion. I don't need to do that for daily driver. The novice, like me, thinks something is smooth as silk and ready for top coat when a pro would say it's rough as a cobb. I can never tell. We tend to put way too much crap on the metal trying to "smooth it out". There is no substitute for sanding but I hate it. I guess I won't get that job at Maaco or Earl Scheib. I really really am in awe of someone who actually likes body work. I can't afford $10K+ for a good paint job. If someone says they will do all that work and paint with good paint, in a booth, for less than that, you may smell a rat.

Its been said that 3 coats of SPIepoxy = 2coats of SPI 2k primer as far as build goes. Some of it's most loyal users only use epoxy for build.
I know you don't need guide coat when sanding it and it sands real easy once the skin is cut.

Good info Caso. thank you.
Just to add another idea, I still have some Preval bottles from years ago when I tried them. Not a bad gig for small areas. I may try the Epoxy with what I have left. It's cheap'ish and partial throw away. It may serve a purpose for some. Home depot: 2 for $9. Not much paint. you would have to reduce the epoxy to 50% but for keeping parts "protected" for months/years with epoxy until HVLP day, couple of thin funky coats is OK.

Get a bag of disposable brushes and a fine nap roller for larger pieces. Faster and easier.
Apply three coats.
When your ready wash em off scuff with 400 or red scuff pad and continue.
The key is to have those two coats as the foundation. Don't sand them off.
Since SPI comes in grey, white and black I like to set the bottom in one color then use more for my 'build' in a different color.
That way as soon as I see the first color I know to stop.

Have fun but use protection...

Guess you are right, brush/roll on. Just seems so non automotive. But I see the advantage. Will do. Great idea about colors. What's wrong with Eastwood or Summit epoxy. Summit epoxy has to come from someone else? and maybe Eastwood also. The reviews are mostly good.

Back when I first started looking into 'what to do' I was thinking rusto... Started reading in forums and came across the great Epoxy war of whether to put filler or epoxy down on bare metal first.

That introduced me to a couple of names that I took note of since they spoke from obvious experience and knowledge. (Sort of like a certain Lincoln known in these parts)
I then started researching the product he was touting. If the reason he was using SPI was it is just as good as the old PPG with lead that was better than the new PPG DPLF(lead free) and less expensive by far, was good enough for him it would save me time and money. Money being my primary concern. I wanted the best cheapest... Or is that cheapest best?

Knowing now what I've learned from HRL and Carb King about 6cyls and 2vrs4 barrel carbs I'd never bother with a 4v setup for a driver. Why? Cause I read a lot but I pay attention to just a few.
So I started following Shine.

re: preval sprayers, I don't believe they will spray the Epoxy without thinning. If the purpose here is three protective coats for maximum moisture protection, then thinning is counter productive to material build. Where brushing/rolling is rather unconventional, given the product will need blocking down the road, any minor defects are not that much an issue. For someone not wishing to spray for whatever reason, rolling gives you good coverage, no overspray issues to deal with, and yet gives you a quality product that is about the best paint substrate you could ask for.

I have read (grain of salt thing) that Eastwood and Summit are reselling Kirker paints. I can't speak to the quality of their products, but if you can get the shipping and discount deals that these guys pass out on occasion, it would seem to make the Kirker paints more appealing. Not sure if you can get a better deal by cutting out the middle man, I think Kirker uses them as a distribution network in much the same way RMD uses Baileigh Industrial.