When I was a teenager I painted my 1961 VW bug metallic green. As I recall, there was a lot of over spray giving the car a fine sandpaper feel to it. Smooth and glossy it wasn't. I want to try again. I will paint my 1987 Honda Civic hatchback which I converted to electric earlier this year. Here it is with original paint.
There are three common types of auto paint, listed here from oldest to newest: lacquer, enamel and urethane. I will spray urethane and use a base coat/clear coat system. With this system, you spray or "shoot" 2 or 3 thin layers of matte color coat, the base coat, followed by 2 or 3 layers of a thicker, durable, glossy clear coat.
August 2009. I bought auto paint. After much internet research, I decided on Omni (PPG's economy brand) metallic blue, but I'll call it Electric Blue.
I am following these steps, in this order.
1. Wash the car with a good grease-cutting dish soap.
2. Repair rust spots.
Honda rear fender wells often get spots of rust around the edges. The driver's side rear wheel well after sanding but before Bondo:
Passenger side rear well before Bondo. Sand down to bare metal:
After 2 or 3 layers of Bondo. I'm also trying to smooth out some creases in this fender:
After sanding, degreasing and priming the passenger side:
After sanding, I sprayed the area with a commercial degreasing solvent recommended by the paint vendor and wiped it off with paper towels. Then I used a self etching primer, also recommended by the paint vendor. Bare metal must be primed with self etching primer.
3. Remove everything that comes off easily.
Front bumper off:
(One reason I like Honda cars? These are two of the bolts that held the front bumper on for 22 years:
These bolts are exposed to road salt, water, dirt, etc. Little or no rust on these. Each one broke free with a little Craftsman wrench, then loosened without effort.)
I cleaned and spray painted any removed parts that needed painting, like the bumpers, the windshield wiper arms, the gas cap door, rear hatch hinge cover panels, vinyl door panels. I made a paint booth in the garage by hanging old tarps from the ceiling. The "whole house" fan under the garage door quickly draws out paint and solvent fumes.
4. Scuff up the old paint.
Several sources including the paint vendor say to use the original paint if you can, since that sits on the best quality primer you can find. I will scuff the surface of the old paint, to give the new paint something to bite into. Many sites say to use primer or the new paint will not stick well. The paint company documents confirm that scuffed OEM paint is a suitable substrate for the paint. I hope this is good advise.
Some areas needed sanding with 220 grit paper. This photo shows worn topcoat, scratches in the topcoat. The edge shows old primer. If I went too far while sanding, I degreased and primed the area with self etching primer.
I sanded large worn areas like the hood with my Harbor Freight DA air sander, then went back over it with a Scotchbrite pad:
5. Wash the car again, to remove all the loose paint dust.
Here is the scuffed car, almost ready for washing:
6. Touch up any black trim before painting the body.
I don't want any spray can over spray on the new paint so I will take care of some trim now. I should try to find vinyl trim for these window strips but I will paint them flat black for now. Here is the primer coat:
Here is the driver's side trim with a couple of coats of paint:
To make masking easier and faster, I built a simple masking machine:
I elevated one side to keep the paper and tape rolls at the edge. There is a spacer for the paper roll to keep it about a half inch from the end. When I pull the paper out with the tape on it, I get a strip of paper with the tape perfectly aligned on the paper edge:
Then I tear it off using the old hacksaw blade edge. This machine makes masking almost fun :-)
7. Mask everything you don't want painted.
I want to paint the door and hatch jams so I have to mask the door openings. Here is a tape web over the hatch to support masking paper:
I still have to cover or remove a few things here, like the hatch supports.
The masked door and doorway:
A note about masking tape. The green tape is 3M automotive masking tape. The blue tape is 3M painter's tape. They are both low adhesion and very forgiving. They stick and easily restick if I make a mistake. The cheaper white masking tape is too adhesive. It's definitely worth an extra buck or two to get painter's masking tape.
8. Practice painting on something.
I cleaned and degreased the inside of the hood to practice on:
Since I was doing a test shoot, I mixed up a small amount of base coat in plastic cups. To my surprise and horror, the cups began to dissolve. I quickly mixed the paint and poured it into the paint gun, a well-regarded cheap gun from Harbor Freight:
There is an excellent spray gun set up page here:
HVLP Spray Gun set up
I was concerned about where the smelly paint and solvent fumes would go when they left the garage so I made a copper and brass wind vane out of junk :-D
I mounted it on a pole in the middle of the yard so I could clearly see the wind direction. It is very sensitive, responding to the slightest wind:
Before spraying, I watched lots of You Tube videos of professional car painters, like this one of Ed Hubbs:
I shot a test pattern on a piece of masking paper. I adjusted the fan control on the left side of the gun to give a 5 to 6 inch high cigar shaped pattern, and adjusted the fluid volume on the rear of the gun until the paint didn't run. This sped up gif shows me starting the second base coat:
Here it the hood after one and a half base coats:
The first base coat had some runs in it so I cut back on the fluid volume. (Some people say to put the first coat on "very wet" while others say the first coat should be a light tack coat...) The second base coat didn't have runs in it. I ran out of paint before I was finished the second coat, but since I put on a heavy first coat, and this is the inside hood I stopped. I cleaned the gun out with lacquer thinner by rinsing the cup with it and spraying it out, three times.
I mixed up a cup and a quarter of clear, this time using a clean glass jar instead of plastic drinking cups!
I shot a couple test patterns on paper, then shot the hood. After two clear coats, it doesn't look much different in pictures, but it is much shinier:
Lots of "orange peel" in the clear, a bumpy finish. Of the several things that can cause this, my problem is probably too much fluid flow for my spray speed. I checked my test patterns and saw that they had run a little. After comparing my technique with the pros, I can see that I am not spraying as fast as I should. Practice makes perfect, though I will be practicing as I paint the car!
9. Degrease the whole car.
I have been using degreaser before priming or painting anything. I put it in a spray bottle so I can spray it on, then I wipe it off with clean paper towels:
10. Wipe the car down with a tack cloth, a sticky cloth mesh used to remove dust.
11. Shoot the base coat.
I shot at least 4 layers of base coat to get complete hiding of the old paint or primer:
12. Shoot the clear.
I must have put 5 coats of clear on the car. Lots of "orange peel." Makes me mad. I'll either live with it, or try sanding with fine sandpaper and polishing:
This is some of the stuff I used:
The white thing at the end of the paint gun is a water trap and filter. The blue bag holds a tack cloth. The white funnels are filters through which the mixed paint gets poured into the paint gun. The plastic buckets are graduated mixing cups. Lacquer thinner is used to clean the gun after painting. The blue cans are clear and activator, mixed 1 part activator to 4 parts clear. The purple can is reducer, mixed 1 to 1 with the Omni paint. The black plastic bag with red letters holds the respirator. In front of the bag is a can of self etching primer for bare metal.
13. Remove the masking tape and paper.
Some paper and tape off here:
14. Give it a warm sun bath:
I would give myself an A for prep work and masking. I would only get a C for the paint job and that's if the teacher liked me.
I talked to a couple people who have experience in body work. One person thinks I was too close, didn't have enough solvent going on while spraying. I could fix it, but not for a month because the paint has to cure. To fix it, I would wet sand with fine sandpaper, then use polishing compound to bring back the shine. That's work, and time consuming, time I won't have in a month.
15. Put the car back together.
Reinstalling the bumbers is easier with a lift. I like reaching up to do things that I used to have to do lying on the ground:
Here is the car with bumpers, windshield wipers, turn signals, parking lights, side mirror, antenna and trim:
You can see that the little gas door is not painted yet. I neglected to paint this so I will have a touch up day when I will paint this, the hatch hinge covers, and a few little spots where the paint lifted when I pulled some of the tape off.
One more pic, after I installed new springs, and I ... uh ... "painted" the little gas door. The rear is now at the original height: