backyard painters. I have a few questions before i dive in.

I currently have a miata that is a track rat/HPDE beater. its past the tolerable point of needing a quickie paint job.  In Jacksonville

I have a "harbor frieght" style HVLP paint gun. a 6 inch sander and more time than money. 

I am considering either the rustoleum/acetone mix and spraying with with the gun. or buying some cheap single stage urethane to paint it with. First thing is first though. I have to get it ready.

With my 6 inch orbital I was going to go at the extremly faded white with some 320.  And then mark anything i feel the need to fill with bondo/putty.

My first question is :. As I am sanding it down some to get a good clean surface to paint. What would be a good suggested primer?

Some things i read say do NOT use spray can primer. because of compatibility issues. I will be piece mealing this over the course of a few weekends and I like the convienence of a spray can I can squirt some out of when needed if i get an hour to work on a panel. I dont want to go through the hassle of mixxing up primer or cleaning the gun every time i get a free moment to work on it some. Is there a decent primer I can use that comes from a can? If i just use rustoleum white primer will it explode and melt down my entire car if i put on a single stage urethane on top of the spray can?

I plan to 320 the original finish. fill and smooth any body issues i find. primer the whole thing. sand that with 400. hit it with some paint. 3-4 coats. sand that down with 320-400. and then hit it with 2-3 more coats. and finish that with 400-600-1000-compound.  its white. its going back white. 

I would just read the cans to see if there is a compatibility issue with the rustoleum primer. If you are really worried go to your paint supplier and ask them to put the recommended primer for your planned paint in a can. If they can't do this, you might want to look for a different paint supplier. 

Also, sounds like you are doing much more than just a quickie paint job! it should come out beautiful if you do 5-7 coats with wet sanding. 

Maybe trade some planned time on your 5-7 coats for extra prep time instead. The prep makes the job. 

p.s. I am not a paint expert. I have only painted cars with rattle cans, but they came out alright!

If you use the Rustoleum, you don't need primer.  Scuff it up with like 320 grit or so, clean it very well, wipe it down again with mineral spirits based paint thinner, shoot it with the HVLP.  I use mineral spirits based paint thinner (NOT the "slow" kind) mixed with the Rustoleum Professional.

I would go coarser on the first round of sanding. I am thinking 180 ish.

I like the Evercoat RAge Gold filler

I like the Durablock sanding blocks

I hate ebay sandpaper

Wax,grease and silicone remover is a must not an option

Tack rags are a must

Buy good tape and a roll of masking paper; worth it.

Then get a gallon of Valspar DTM2008  primer surfacer: Depending on how it is mixed, it serves as both a direct to metal polyurethane primer or a thicker high fill surfacing primer. There are other brands of this type of product, but this is what I have the most experience with.

Shoot the Valspar on the panel as a high build and sand to about 300 or so. Then shoot a sealer coat of the Valspar and sand to 400 first and then 600. Squirt the color on top of that 600. For a race car I would not bother with base-clear.

How straight do you want this to be? Reason I ask is that the 6" palm sander is going to make waves not take any out. To make stuff flat you need a sanding block that covers at least 12" or as much of the panel being sanded as possible; it has to be longer than the waves in the panel since the goal is to sand the tops off the waves and fill the troughs with filler/primer. 6" sander is just going to ride up and down on the waves and make them bigger. Using too fine of a grit will do the same thing. Coarse paper makes stuff flat. Fine grit makes it smooth. Flat and smooth are not the same thing.

You can buy epoxy primer in a can. It is a special can with a pin that releases the catalyst and you than have a limited time to use the product. I have not used it so cant comment on results. It is expensive. Typical rattle can primer is going to promote rust by the nature of how primers work.

When you think you are ready to paint over the sealer, wash the car to get rid of dust and then have a look at the wet car to check if you can see any flaws. The wet sealer is going to look like a clearcoat finish and show any flaws and give you a good idea of the quality of finish you are going to end up with. That is water over Valspar sealer sanded to 600 grit.

Another thing you can do is use water in your spray gun to practice painting the car. You dont need to mask up you or the car and it will let you plan the order of painting operations. Will also give you a feel for how heavy a full gun gets when painting the middle of the roof or hood and how that can cause your concentration to slip for just an instant and berkeley up a panel!

Pacewise, you should be able to get one panel done in a weekend. That is what I would do.

Recap:

1. Scuff the panel down with 180 You want the clearcoat gone for sure but we aint shooting for bare metal panel.
2. Bodyfill over the dents or low bits
3. Mix as a high build and scuff to 280 0r 320 until it is flat.
4. Mix as a sealer coat and 2 step 400 to 600 so it is smooth

Paint with 2 or three coat of color.

Pete

If you spray with Rustoleum, the primer in a can works just fine.  I've even used it under cheap single stage acrylic enamel without problems.  If you go to a urethane paint, the solvents in the urethane don't react well with the primer in a can, and the primer will crack, peel, or bubble under the paint.  It's not a lot of fun.

I've sprayed Rustoleum a few times before, and had the best luck using VM&P Naptha as the thinner.  It's been my experience that Acetone flashes off too fast, doesn't let the paint self level, and leaves a lot of orange peel texture.  Mineral spirits flashed too slow for me, and caused runs if you put the coats on to thick.  Naptha was the "just right" for me.  I also suggest you add a hardener to the Rustoleum, you can get it at Tractor Supply or any other farm store.  It makes the paint set up much, much harder and more quickly.

I've also shot the acrylic enamel from https://www.paintforcars.com/ and had good results.  It's barely more expensive than Rustoleum by the time you buy Naptha and hardener for the rustoleum.  The results are better though, much better gloss and much more durable.  The enamel also plays nice with the spray can primer.  This stuff comes out great with just a 1200 grit sand then compound.

No matter what you spray over rattle can primer though, it's important that your first coat is sprayed pretty light, and allowed to "flash" off before you put heavier coats on.  It's the solvent that causes the issues with rattle can primer, and by doing a light first coat, you allow the solvents to evaporate quickly and put down a barrier between the primer and the paint.

Hope that helps. Good luck!

Just joining out of interest.  I'm terrible at paint and I'm thinking about painting my truck this spring with flat brown.

In reply to NOHOME :

almost every time i read one of your posts, i learn something.   practicing with a gun full of water is friggin' brilliant.   thank you for that.

In reply to NOHOME :

How straight do you want this to be? Reason I ask is that the 6" palm sander is going to make waves not take any out. To make stuff flat you need a sanding block that covers at least 12" or as much of the panel being sanded as possible; it has to be longer than the waves in the panel since the goal is to sand the tops off the waves and fill the troughs with filler/primer. 6" sander is just going to ride up and down on the waves and make them bigger. Using too fine of a grit will do the same thing. Coarse paper makes stuff flat. Fine grit makes it smooth. Flat and smooth are not the same thing.

I dont really care about straight. and its a miata. kinda small.  white covers some flaws pretty well. and so does keeping it moving on the track. ha ha. 

I'll take you up on the other ideas.  I planned on spending more on tap/tach/ mineral spirits and sandpaper than i do on paint. 

I’ve done several racecars similar to NOHOME’s method and while I’m no painter they came out presentable and held up well. Please get yourself a good respirator with fresh filters AND wear it while priming and painting.   Urethane is a good product but nasty to breathe.

In reply to Curtis :

When you're close to ready, let me know. My schedule currently sucks in terms of not working weekends, but I'd gladly head up to lend a hand. 

What about weather and working outdoors? If I get one panel completely flat, smooth, primered, and sanded to 600, can it get rained on until I'm ready to spray color? Or does it need to be inside the entire time?

Make sure your paint gun doesn't require more air than your compressor can deliver.  I was in line behind someone at HF a few weeks ago was returning a gun for that reason. I guess there's a numerical rating (ex. 6 CFM @ 40 PSI).  

I did an older car with rustoleum from a gallon jug...I don't rememer what it was mixed with.  Primer and sanding will fill and smooth out any minor imperfections.  

In reply to Hoondavan :

1000x on the primer and sanding and I'll add that going with 2-3 extra top coats (thin!) then wetsanding will take car of orange peel, fisheye and overspray. Spend extra time (seriously 40-80 hours extra on those steps, yes it's a ton of time, but it's the easiest and some of the most relaxing, though tedious work) and you'll have something that looks closer to concourse than racetrack. 

captdownshift said:

In reply to Hoondavan :

1000x on the primer and sanding and I'll add that going with 2-3 extra top coats (thin!) then wetsanding will take car of orange peel, fisheye and overspray. Spend extra time (seriously 40-80 hours extra on those steps, yes it's a ton of time, but it's the easiest and some of the most relaxing, though tedious work) and you'll have something that looks closer to concourse than racetrack. 

"you'll have something that looks closer to concourse than racetrack. "

god  I hope not. 

But another $10 HF hvlp guns for primer. Never never ever ever try to make one gun do two jobs.

If you get the warranty with the paint gun you don't even have to clean it according to my harbor  Freight. 

The warranty was cheaper than solvent to clean the gun. They've traded it out for five times now.

So when I did my miata.... I spent almost 4x as much on sandpaper than I did anything else. 

I did panels one at a time when I had the time, covered them in primer, and put them back on the car. Eventually the car was 4 to 6 shades of primer. When everything was covered, I sanded it and hit the whole car with sealer primer from NAPA. A quart is more than enough but it was still $25 or so. 

Atfter the car was a whole uniform primer, it was probably a week before the weather cooperated enough to paint. I really wish I'd thought about trying to paint the car with water first, that would have made finding a good pace far easier.

2 harbor freight guns. I put a dryer on the base of each on, in addition to a dryer at the compressor. Maybe that was overkill. 

Still, that's the only car I painted so the advice is worth what you paid for it. 

maschinenbau said:

What about weather and working outdoors? If I get one panel completely flat, smooth, primered, and sanded to 600, can it get rained on until I'm ready to spray color? Or does it need to be inside the entire time?

If the last coat is the urethane sealer/primer, then yes you can get it wet.Recall this is the coat that I shoot water on to check the finish/reflection.  But regardless, you are going to want to scuff and wipe the panel before you paint it, so the goal is to have the layer under the sealer as close to perfect as possible, then shoot the sealer, don't sand it,  and come back the day you want to paint. Sand the sealer to 600 and paint.

More on the cheap/crude end of the spectrum, several years ago I painted a bunch of rowing boats with Interlux Brightside yacht paint.  It's about $40 a quart.  Single part paint, pretty cheap, just thin it and spray.  It liked to orange-peel on me a bit, but it was presentable.

I had the opportunity to see these boats last summer, and the paint still looks brand new.  And they spend 100% of their time outdoors under bright Colorado mountain sun.  That's  a big dose of UV.

The NAPA Gold 5.0 urethane single stage goes down really, really well. It's what I used for the stripes on the Targa Miata as well as a Miata hardtop. If you're on a budget, this means you don't have to pay for clear which sprays quite differently from a color coat. NA Miatas didn't have clear from the factory with the exception of (I think) black.

The small HF gun also works better than the big one. I'm guessing nozzle size, but I don't have it handy to check.

This thread is great -- I did my rallycross car 6 months ago and did Rustoleum because I am afraid of isocyanates in my home garage.  AFAIK the only isocyanate free shadetree methods are rustoleum or laquer right?  I freaked myself out reading about isocyanates and need for supplied air, etc.  The rustoleum did the job for this rallyx beater but I am trying to explore options for next time.  

I filled in dents/dings with bondo, sanded down to 400 grit level.  Remainder of factory paint was scuffed with 320 grit.  Used rustoleum primer out of a can, followed by gloss white thinned with mineral spirits.  It layed down well I think.  I tried to use the rustoleum enamel clear over this which was a mistake (could not get even coverage without runs).  I should have just done multiple layers of enamel, and resigned myself to frequent polish/wax.  Meguiars ultimate compound for cutting and then polish made a pretty nice finish for what it is ...

Wow that looks as good as I need or car to want. 

so you just used rustoleum canned spray primer? white I assume. 

dinger said:

If you spray with Rustoleum, the primer in a can works just fine.  I've even used it under cheap single stage acrylic enamel without problems.  If you go to a urethane paint, the solvents in the urethane don't react well with the primer in a can, and the primer will crack, peel, or bubble under the paint.  It's not a lot of fun.

I've sprayed Rustoleum a few times before, and had the best luck using VM&P Naptha as the thinner.  It's been my experience that Acetone flashes off too fast, doesn't let the paint self level, and leaves a lot of orange peel texture.  Mineral spirits flashed too slow for me, and caused runs if you put the coats on to thick.  Naptha was the "just right" for me.  I also suggest you add a hardener to the Rustoleum, you can get it at Tractor Supply or any other farm store.  It makes the paint set up much, much harder and more quickly.

I've also shot the acrylic enamel from https://www.paintforcars.com/ and had good results.  It's barely more expensive than Rustoleum by the time you buy Naptha and hardener for the rustoleum.  The results are better though, much better gloss and much more durable.  The enamel also plays nice with the spray can primer.  This stuff comes out great with just a 1200 grit sand then compound.

No matter what you spray over rattle can primer though, it's important that your first coat is sprayed pretty light, and allowed to "flash" off before you put heavier coats on.  It's the solvent that causes the issues with rattle can primer, and by doing a light first coat, you allow the solvents to evaporate quickly and put down a barrier between the primer and the paint.

Hope that helps. Good luck!

Hmmm- I'm guessing that the solvent problem is why I had so much trouble with the two-tone painting of the Rampage. But it's weird that it would have that issue given I was using two different colors of the same Rustoleum paint (though one was metallic and the other not).

I don't mean to thread-jack -figured it would be better to ask here.

I'm looking to paint my RX-7 and I'm wondering if the current, questionable paint that flakes off if you accidentally hit it too hard, would need to be completely sanded off, or could I get away with "basic" sanding and then a re-shoot?

NOHOME has stellar advice if you are spraying. Just follow what he recommends.

Spraying makes such a mess at home. For giggles I painted my last race car using the roller method.

Downside is it takes multiple coats to get a nice finished product. Upside is the endless hilarity of telling people you painted it with a roller. The entire job with 2 quarts of Interlux Brightside and all the materials was around $120. I did not sand and buff it. If you can develop a good 'tipping' technique the finish will have a high gloss and few brush marks (though keep in mind I used light colors which hide a lot of that). This method does not negate any of the prep work required vs spraying though. It is more labor, less mess, probably a bit cheaper, requires no compressor and you won't be able to stop laughing at what you're doing while you're doing it.