I am getting ready to repaint my Z. I am going to do it myself due to lack of funds. I have a sprayer. What are the steps you do when you paint? What is wet-sanding? any help would be appreciated.
1. sand it down to the metal (400 grids)
2. fill and repair rust and things
3. prime with grey self-eching primer
4. Sand back down to 400 grids.
5. check for flow on the body and repair
6. prime with polyotharene primer (yellow)
7. sand it down again
8. spray 1st coat
10. wet sand with 1500 grids
I would heartily recommend you do get a book, there is just way too much to cover.
I'll give you a few things.
Although yo2001 summarized the process quite succintly, I would offer a couple different things.
If your prior paint job is SHOT, i.e. blistered, peeling, crazed, cracked or so totally sunburnt or worn through that there isn't much there, then yes sand down past the paint at least to the primer, and feather that out. If you are going all the way down, rather than using 400 grit sandpaper (hand or D/A) I would recommend you use 220 grit with a Double Action Sander (D/A) and no, this isn't your wax buffer with sand paper attached.
Sand down smoothing the prior paint and primer. If you encounter or have dings, dents or other imperfections, that require body filler do those first. Finish the repair so that it's smooth to the touch, (hint: don't look at the repair, let your hand feel the surface)
If the car is now finished and ready to go to paint, either use non-sanding primer or primer sealer. If however the body is still in need of some final smoothing, due to small dents or dings, then use medium fill primer, and wet sand the whole car down.
Wet sanding uses that black sandpaper on gray paper, and of course, water. The process is straightforward, wet sand the body using water to help cut the primer and carry away the powder. As you sand, feel the body for any imperfections, if you find any, fill these areas with Red-Cap (thickened primer) that you smear on with a spatula or rubber squeegie, let dry and then sand smooth. For the wet sanding process I would use 400 grit wet/dry sand paper. If you use red cap, I would recommend you use 280 or 320 to get it to almost finished, then top coat that area with new primer and finish that with 400 grit.
A second coating of primer isn't necessary, unless you cut through the primer to the metal. If you want to be assured of a problem free finish, rather than using primer, use SEALER. This helps seal the underlayment from the finish coat. This typically is a non-sanding item (i.e. no sanding required if applied smoothly) as long as you top coat it within the period alloted (usually 24-48 hours).
Painting in a nutshell, is apply your first coat slightly thin, i.e. just barely fogged on, 10 - 15 minutes later, apply a proper double wet coat, a third coat is up to you.
Let the paint cure the minimum period required according to the paint you used if you wish to clear coat. However, in order to clear coat, you'll want to "cut" the surface of the paint with 800 or 1000 grit paper to give the clear coat something to adhere to.
Apply clear coat, and let cure. This usually gives you a very shiny durable finish, for the utmost in gloss, you need to let the car cure for as long as 4-6 weeks before you once again, sand the car down, this time with 1200 or 1600 grit, then using a power sander with a buffing wheel, rub it out with polishing compound, swirl remover and finally glaze.
Now you see why I recommend the book? There are probably 15 questions for each paragraph above. Good Luck.
A good book to get is "Automotive Paint Handbook, paint technology for auto enthusiasts and body shop professionals" by John Pfanstiehl. It is very easy to read and explains all the steps for a first-time painter. It is $12.50 at amazon.com. This book is als very current. It offers a brief history of automotive paint and has a guide of which products to use. It lacks a little on specific directions but when you buy your painting supplies they will have the specific directions on them.
bakachan and kenafen both have a good suggestion. (smacking myself upside the head for not having thought of it)
By doing the prep work yourself you'll save chunks of dollars, since that is what is the most time consuming. The actual masking and painting is relatively quick and other than the expertise required to do it right, pretty straight forward. It is the removal of all the chrome pieces, and other items that shouldn't be painted, as well as making sure the body is straight and ready to paint that can make the difference.
I remember years ago, seeing a guy's car at the Air Force base where I was stationed, that he had had painted by the Scheib people. He had cut corners, and had told the guy at the paint shop that all he wanted was the CHEAPEST job they could do. Basically, as the ad says where Earl Scheib himself says "I'll paint any car for $99.95" He didn't want to pay additional for masking, (other than what they HAVE to do in order not to render your car illegal by DOT standards, i.e. headlights, tail lights, windows, mirror face and side marker lights).
His car ended up having the grille, the chrome rings around the headlights and taillights, the door handles, door locks, the trim around the windshield and rear window, the chrome trim going around the wheel wells and the little individual letters for the make of his car all painted this baby blue. It was hilarious. I wish I had taken a picture, but he wasn't too **** happy about it and I'm sure that would have set him off.
He spent more time cleaning off all those pieces, and paying for using the MWR Auto Bay than if he had gone ahead and let them mask it for him, or if he had taken the time to remove them prior to the paint job. But he did get a $99.95 paint job!!
Nonetheless, other than the obvious error of painting parts that shouldn't get painted, the rest of the car was pretty good. No runs, no sags, not the thickest paint job I've ever seen, but enough to cover the metal. So, you can get it cheap.