Autobody Paint Tech 101:
First, some clarifications: A “Paint Store” is not your local NAPA. Find a paint store! NAPA is good for small quantities, but they do not mix paint. You will find your best selection at a pro paint store.
There are many manufacturers of paint. I use PPG Starbase, DBC, or DBU as a basecoat. Starbase is lacquer. DBC is better. DBU is best, adding a catalyst to the thinner (reducer) to make the base color chemically cure. Some painters like other brands. The important thing to remember is to use the same manufacturer throughout the process. If you use X brand primer, use X brand clearcoat. Keep it consistent. The chemical composition is very important. I like PPG (the most expensive). This article will use PPG products because I am familiar with them.
One thing about painting a car: the bodywork labor is at least 50% of the job’s price. That leaves 50% for materials. Why scrimp on the materials? Use the best you can afford!
The paint store salesmen are your friends. They are highly trained on all the products they sell. They can teach you about paint. Ask for it! A motivated paint store salesman will teach you about his products. He sells more paint that way. I once had a tech take me around back and teach me how to color sand and buff on a fresh black paint job on my 440Z Cabrio. I have since bought $500 worth of sandpaper and buff compound/pads from that store… not including paint.
Bodywork:
Walk around the car and look at it. Park it in the sunlight and close your eyes. Feel along the car and sense the difference in the surface temperature of the metal. The bondo will be colder than the metal. Mark or remember the cold and low spots. Your fingers and palm will be a better judge of low spots than your eyes. The old magnet trick works to find filler, if you remember that the magnetic properties of the substrate are all relative to the bare metal. A calibrated magnetic gauge is available that tells you the thickness of the paint, available at paint stores.
Preparation:
You may need a dual-action orbital (DA sander). There are two kinds, electric and air-powered. Air ones use a minimum of a 3-horse 20-gallon compressor. Expect your compressor to run nonstop while sanding. I use an electric DA sander, made by Porter Cable. I don’t have to fire up a 15-amp (110v) compressor to run a 1 hp sander. Electric DA sanders are very quiet. Some have dust attachment hoods that use a shop vac to collect the sanding dust. Dig out the low spots and the bondo spots. Any filler in your car is either old and inferior, or fresh and poorly done—assume it!
Clearcoat:
Urethane is in. A decent clearcoat job will be as shiny and deep as the old lacquer jobs. Lacquer is out. I believe it is completely banned in CA now. When I left in ’95, all that was left on the shelf was primer, sold as a ‘precoat’. Urethane clears can be sanded and buffed to a mirror finish, if you like. They are very durable and have UV inhibitors. Great stuff. The neat thing about a clearcoat job is that the basecoat color goes on like lacquer. You can sand it in the booth if you make a mistake, and it dries fast too.
Painting Vinyl and Plastic in a Z:
There are two sources for the dye. If you don’t have a paint gun, find SEM vinyl dye at a good paint store. SEM is the only way to go, and I have never found another product that works as well or lasts so long. It also looks totally natural. They have Satin Black for your 240Z, and Napa Red for your red 240Z. They have ZX colors too. Please do not even consider any other brand. Been there, done that. In my experience, no other brand has the correct gloss, durability, and chemical composition to bond to the vinyl.