I picked up a 2003 Toyota Celica T-Sport as a summer project! Mechanically, it's mostly fine but the paintwork is where the most of my work will be in. It's got 117k miles and was sat parked for 12 years, so it's had quite a lot of damage from the environment.
I plan to fully repaint 8/10 of the body panels by myself, the front and rear bumpers are okay. I will need to:

• Sand the car down

• Repair rust spots (using rust converter) and fiberglass body filler if needed

• Body fill any dents (sanding after)

• High Build Primer (sanding after again)

• Sand more

• Basecoat

• Clearcoat

• Sand again (you guessed it!) and polish

• Interior detail

• Few bits and bobs that need replacing

This is my first time ever using a spray gun. I bought a compressor and the full setup I will need. It's going to be a HUGE learning curve to overcome, painting a car is not easy, plus I'm doing it outside. The paint is metallic so it's harder to get right too, but I love making myself struggle so here we go!

Wow. This is HARD.

The last month has come with plenty of pain for this project.

To start with, it took time to learn how to set everything up for paint, as well as mask the car. I watched lots of videos on it all. Oh, and cleaning the gun and area too. I bought two different types of paint thinner, a cellulose-based thinner and a 2k thinner. I am using the cellulose thinner to clean the gun out since it is cheaper.

I spent around 3 days sanding, including sanding rusty areas to bare metal and using rust converter, as well as using body filler.

After a few long days of failing to lay down the high build primer, I spoke to a professional at a local paint shop when I was buying the basecoat. I was using a 1.6mm nozzle, which is recommended for my high-build primer, but it was spluttering everywhere making the finish horrible and coming out inconsistently. He advised that I switch to the smaller 1.4mm nozzle, and told me that it doesn't really matter how much thinner I use to get it to come out of the gun right. It just meant I needed to do more coats. After switching the nozzle and adding more thinner, it laid down REALLY well!

Now, time to talk about the basecoat.

FIRST ATTEMPT

My first panel to tackle was the bonnet, which failed due to sandpiling. Essentially, the paint looked rough and sandy, which is caused by too high of a pressure and the gun being too far away.

No problem. I tried to sand the clearcoat down (I learned now, if the base coat doesn't look right, clearcoat doesn't fix it.), but it gummed up my paper too much. It turns out that the cure time of 48 hrs only applies at the specified temperature ranges, so overnight since it is cold, it is not curing. I will tackle the bonnet later when I have finished the rest of the car, I thought.

SECOND ATTEMPT

This time I was tackling the small rusty area behind the wing mirror, which was very poorly taken care of by a previous owner.

Since it was a small area, I used the spray can of high-build primer, and sanded it down smooth. It always looks so great after primer. 

I lowered my air pressure, and moved the gun closer. I was very nervous since my previous attempt went so poorly, but I moved on anyway.

The paint laid down really nicely and it looked great. Then, all of a sudden, it started melting away in one go. As it turns out, the spray can primer was cellulose-based, and unless you let it cure for a few days FULLY, adding a 2k-based basecoat on top will remelt the primer back down. WHAT A DISASTER. More sanding needed to fix this one, and I will stick to the 2k primer.

THIRD ATTEMPT

Primer-ing the rest of the car went really well, as well as redoing the rusty mirror area.

I was all set to do the base coat. This time, I was ready to do the rest of the car in one go, since the basecoat went down so well before melting away.

I lay down my basecoat, but it isn't sticking properly. It was landing wet, not sandy, but it was clumping up as if the surface was hydrophobic. I continued with the light coat, hoping it would get better. It did, but it's not up to standard still. There is still minor sand-piling, which really confused me. If I'm honest, I did not touch the car for the rest of that week and afterwards the rain settled in so I couldn't paint. From my understanding, it was way too hot outside for basecoat, since it was around 25 outside, so it was drying in the air partially still before landing on the panel.

As for why it wasn't sticking to the panel initially, I believe it can be due to three things. 

• Firstly, I was using the cellulose thinner as a degreaser (I read online that this is okay, but it might not be after all). Apparently, this is not a proper degreaser, so there can be plenty of oils on the paint that were not coming off. Instead, I will use Isopropyl Alcohol since realistically the only oils on the paint are from my hands, and soapy water + isopropyl alcohol will get rid of that.

• Secondly, the primer may have needed longer to cure after sanding. When the basecoat lands on it, it might be partially softening the primer, making it not stick. So I will always wait at least 24 hrs next time.

• Thirdly, I believe I may need a primer sealer. I have seen plenty of people using sealer and not using sealer, but maybe I need it for my case.

Altogether, I've spent around 70 hours on this project over two weeks and not a single panel is done. I'm still motivated to finish it, and in fact I'm really enjoying the process, but I still have lots to learn until I'm able to figure it all out.