I have been reading the postings about paint. I'm ready to start sheet metal work now and am confused about the prep. Some say strip. Some say not to strip. Can someone let me know the why's and why not's.
Thanks.
Jan

IMO, the best substrate is undamaged OEM finish. I don't see any advantage to removing this and exposing the sealed out metal. Also, the priming process is already done, why disturb it?

The best thing to do is strip everything down to bare steel. Then do the body repairs, and prime everything with a good epoxy primer. Why cover up old paint, that may crack/peal, under your new paint job. It's a disaster waiting to happen. You also never know what is under the old paint. You may be covering old body work, that could go bad in the future. Do it right, strip it, and start with a clean slate. You'll be glad you did.

The best thing to do is strip everything down to bare steel. Then do the body repairs, and prime everything with a good epoxy primer. Why cover up old paint, that may crack/peal, under your new paint job. It's a disaster waiting to happen. You also never know what is under the old paint. You may be covering old body work, that could go bad in the future. Do it right, strip it, and start with a clean slate. You'll be glad you did.

X2 if you have the time yourself or the $$ to pay someone else the extra....for sure.

Woo take it off baby!!:D

If she's good lookin, then yes, strip!

I decided to strip down to factory primer. The only place I mess with that is where there is repair needed.

If your existing finish is good, then it's not neccessary to strip to bare metal. On my 70 I plan to address the areas that are in need of body work- but just block sand the rest and paint over what's already there.

There's nothing wrong with painting over a properly adhered existing finish as long as you prep it correctly.

On the other hand- if you're doing a show quality restoration, or have your doubts about how well the existing paint is on there (or what may be under it)- then strip it down if your budget allows. You can do it either way- it's your preference.

Nooj

I decided to strip down to factory primer. The only place I mess with that is where there is repair needed.

I forgot to clarify: I am stripping down to factory primer beause the car had been repainted once before. The top coat of paint came off with very little stripper. The factory paint took significantly longer to strip. Had the car had a factory coat of paint only, I would have sanded that down a bit and went from there. :)

I have always been a believer in stripping down to bare metal, I want to know whats been done in the past, I need to know where the weak points might be. I know some may not believe that the factory also uses body filler. I always remove all old body filler factory or not and start over. I have done it this way for many years, but I get to be very anal on my cars. I also know its an extra expense and work, but to me its worth it.
Just my opinnion.

I forgot to clarify: I am stripping down to factory primer beause the car had been repainted once before. The top coat of paint came off with very little stripper. The factory paint took significantly longer to strip. Had the car had a factory coat of paint only, I would have sanded that down a bit and went from there. :)

You used chemical stripper and plan to paint over that primer that is left on the car.....that has likely absorbed the chemical stripper? Arent you asking for adhesion and other problems by doing this? And if there was any kind of filler on the car - double whammy because its soaked up there too. :confused:

I'll find out soon enough. I will clean and primer all parts that I strip and repair, plus there will be a coat of paint to block sand off before the actual paint is applied. I would think if there is a problem, it would show up at some point before the job is done.

Strip it...... I had a perfectly straight body until I started stripping.
Smooth straight tail panel...
http://i217.photobucket.com/albums/cc210/furball8994/DissAssembly/th_000_0291.jpg (http://s217.photobucket.com/albums/cc210/furball8994/DissAssembly/?action=view&current=000_0291.jpg)
Note the thickness of the bondo..
http://i217.photobucket.com/albums/cc210/furball8994/DissAssembly/th_000_0293.jpg (http://s217.photobucket.com/albums/cc210/furball8994/DissAssembly/?action=view&current=000_0293.jpg)
I also discovered that my "straight" fenders had rust repairs done at the point where the Battery tray attaches. They were beaten in to make room for a patch to be welded over the rust, (nothing cut out or removed) then Bondo'd over (nearly 1/2" thick in spots) to smooth it out. None of this was visible from the inside...

Strip it...... I had a perfectly straight body until I started stripping.
Smooth straight tail panel...

I also discovered that my "straight" fenders had rust repairs done at the point where the Battery tray attaches. They were beaten in to make room for a patch to be welded over the rust, (nothing cut out or removed) then Bondo'd over (nearly 1/2" thick in spots) to smooth it out. None of this was visible from the inside...


Excellent point. Sometimes a good finish can be hiding problems underneath. There's nothing wrong with bodywork that's been done correctly under the paint- but it's when you find 1/2 inch thick bondo layers that make you feel sick.

I've found similar "repairs" on my '70 that I plan to address.

Nooj

In my experience I have found it to my benifit to take it all the way down to the metal. I do this by using a D A and 40 grit and no stripper solvent. I have seen cases where the stripper will cause the new paint and or primer not adhere and you got to start all over again. Given that and the higher costs these days of body shop supplies and paint I strip it to the metal take out all former bondo/filler and either replace what needs replaced or repair it right. Also with a car the age of 40 YO or more you have no way of knowing what has been painted and what body panels are original to the car and what type of finish you have on different places in the car. JMO.

You'll be making a huge mistake painting over a partially stripped surface. The stripper has softened the original paint and prime and laying a new coat of paint on top is asking for some serious grief. It may cause problems immediately or it may not. Why take the risk? Strip the rest off and start from bare metal. Then you'll know there are no potential problems to bite you later on.

Tom

Jan,
There is a place in Wauchula, FL on the left coast. that will strip your whole body if you want. Plus small pieces too.

http://www.autorestorationdepot.com/about.html

Auto Restoration Depot, Inc.
122 South 8th Ave.
Wauchula, Fl 33873

Phone: (863) 773-9152 or
(863) 773-2545
Fax (863)773-9074
Email: cars@autorestorationdepot.com

I always go to bare metal so you have control of the finished product. Not going to bare metal is like putting new socks over your old stocks IMHO