How to prep a car or paint

[bemmerguy714]

As some of u know my car WAS off to paint shop. After some incidents with the paint guy i decided i'd prep the car my self for being sent to paint. There is rust but i have a freand who is good at welding.

My question is this: What process(es) Have you guys did to get ur zs original paint off. What send paper? Wet or dry? How long did it take. I need every deatail please. I really no nothing of body and paint, so this will be my first time. PLease tell me how to strip me cars paint!!!!

My goals: Have the cars body (no paint at all) showing. Rust will be delt eith also but any advice on how to deal with rust is good too. I was thinking of cutting the rust out and welding another peice in.

I have searched before i posted this message and i didnt find a "best way". I need to know the downsides (if any) to ur procedures as well.

Any body advice someone might have would be much appreciated.

Thanks in advance.

Matt

[mriz]

I'm far from an expert but I just finished the front of the Z32 with some coaching of a body shop owner/ neighbor. You don't need to sand to metal if the paint has good adhesion.If you decide to strip it clean you can use aircraft stripper. Do the best prep work you can or it will show up. If you can feel any imperfections with your hand you will see it. Make sure you degrease/clean before sanding/scuffing or new paint will lift. If you prime it is best to use the same paint system as the painter I am told. I'm sure others will have more to add. Good luck

[EScanlon]

Here's a place to begin learning:

http://www.lambolounge.com/Body/Paint/paint.asp

We've had this very same question posted numerous times, do a search and sift through them to get a mini-education.

If you truly want a unique and excellent job, I'd go back and patch things up with your painter.

Remember this though, the FINAL look of ANY paint job begins with the prep work. You're already talking of stripping off ALL of the prior paint without knowing whether you need to or not. That is one of the most common misunderstandings about painting a car.

Don't just go by the "everyone knows" myths, almost all of them aren't true in every instance, and so many are so plain old wrong that they serve as instructions to avoid.

Enrique

[jmanz6]

If you only have one layer of paint (original factory paint job), then you probably don't need to sand to metal. My car has 7 layers, including the original. I am going to go all the way down because the last two paint jobs were done very badly. When I get to the original paint, I will stop sanding if it appears to be adhered well. I would read up on this before you go willy nilly sanding the paint off your car. Stripper works very well, but you MUST be sure to get it all off. If there is any inside seams or between panels, it WILL cuase your new paint to lift. Also, if you do the prep work, I bet your painter won't warranty the paint job. he can't be responsible if you screwed up the primer. When you do sand to bare metal, be sure to prime it immediatley or it will flash rust. Use an etching primer that you shoot in a gun, NOT rattle can junk. If you are going to do that, you might as well stop now and buy a car that doesn't need repainted. As mentioned before, you should use the same products your painter will use. If he uses PPG paint, you should use a PPG primer. Take your time and good luck.

[bemmerguy714]

If you only have one layer of paint (original factory paint job), then you probably don't need to sand to metal. My car has 7 layers, including the original. I am going to go all the way down because the last two paint jobs were done very badly. When I get to the original paint, I will stop sanding if it appears to be adhered well. I would read up on this before you go willy nilly sanding the paint off your car. Stripper works very well, but you MUST be sure to get it all off. If there is any inside seams or between panels, it WILL cuase your new paint to lift. Also, if you do the prep work, I bet your painter won't warranty the paint job. he can't be responsible if you screwed up the primer. When you do sand to bare metal, be sure to prime it immediatley or it will flash rust. Use an etching primer that you shoot in a gun, NOT rattle can junk. If you are going to do that, you might as well stop now and buy a car that doesn't need repainted. As mentioned before, you should use the same products your painter will use. If he uses PPG paint, you should use a PPG primer. Take your time and good luck.

i have two layers that i know of. The original and a cheap paint job on top. I even see some red that they used under that paint.

[LanceM]

Sanding is probably the easiest way to remove the paint if you want to do it yourself, chemical strippers are available but will also remove bondo and glaze which you may want to leave if you find them. 100 grit will get you there pretty quick, plan on using plenty of sandpaper. Watch that you don't round any sharp edges. If the rust is just surface pitting a small sandblaster would be the tool of choice. If the rust has gone through the panel then replacement is the only option for a long-term repair. Work on one panel at a time, when it is stripped and repaired use epoxy primer to seal it, any other primer is porous enough that moisture can invade and actually cause rust under the primer which will come back to haunt you long after the final coat of paint is on. Don't worry about sanding scratches in the metal at this time, typical epoxy coating thickness is only 1.0 mil which won't hide anything.

Once you have the car completely sanded and epoxy primed, scuff the whole car, assuming that it's been more than 3-5 days since you primed the first piece, a red scotch bright pad works well, be sure to scuff every part as the next coat of paint is going to depend upon this for a mechanical bond.

Now comes the time to fill the scratches and level the panels. If panels need to be leveled use a glaze and a long block sander right over the epoxy to take out ripples and dips. More than likely you are going to be using a 2 stage paint for the final job, a base coat clear coat system. Under this type of paint you best use a urethane primer, a 2K high build primer would be my choice, and lay down two coats. Read the tech sheet for the primer you are using, it will tell you how long it needs to set before sanding. At this point I would block sand the car using 320-400 grit on a long board, you will end up sanding off most of the primer you just put on, you are using it to fill the sanding scratches in the metal. When done 2 more coats and wet sand using 400-600 grit wet and sand for a smooth surface. Unless the sanding marks are very deep they should be filled and hidden, if some remain spot spray those areas and resand as required till they are filled, using care not to sand a dip in the paint!

Typically it is best and recommended by the paint manufactures to stick to one brand of paint, of course if I sold paint I'd want you to buy it all from me too If there will be time, say a week or so from final prime to paint I wouldn’t worry about it as the primer will have fully cured and the basecoat will be depending upon a mechanical not chemical bond to the primer so there shouldn't be any problems with interaction between the paint brands.

There it is in a nutshell, I've skipped some things and just glossed over the rest, it's not hard to do but is very time and labor consuming to do right. Do a google search on auto painting, there are lots of sites with good info.