Topic: Paint, Single Stage?

[Smokey 15]

 I agree. You are the one paying. You should be the one who makes the choice.

[CharlesTurner]

If a current paint formula is not satisfactory, a competent paint shop should be able to match an original sample.

[mikelj5S230]

Just be sure it has good orange peel.

[jwc66k]

Let me toss a monkey wrench in the paint can -
https://www.yahoo.com/autos/how-something-you-spray-on-your-kids-can-melt-your-128334848277.html
Jim

[cobrajetchris]

One thing to consider when discussing paint durability with your painter is to remind him the car will not be subject to the harsh conditions that a car driven every day and sits out all year will. For example I painted my 70 Boss 302 in 1989 with Dupont Centari enamel single stage with a hardener and the car sits in the garage most of the time like most of our cars but does get driven and has sat out at many hot summer day car shows and the paint still looks great with no fading. If this car was driven every day and sat out all the time the finish would be shot in a few years as this product had a fading problem back in the day. Since your painter didn't explain what his concerns are about the single stage hardeners I assume it's either durability or the flow of the finish. The older paints did have more peel and if you want it original that is the way they where. All that being said I think you will be satisfied with either single stage or base clear but don't feel it's really needed on a non metallic color.

[J_Speegle]

One thing to consider when discussing paint durability with your painter is to remind him the car will not be subject to the harsh conditions that a car driven every day and sits out all year will. ...........

+! if its going to be stored/exposed ALLOT outside. It might help but has not for me

On my third coat of paints (BC/CC) on my 2000 F250 and its peeling again.    Unfortunately the shops knowing hat it will be always outside has not helped

[Smokey 15]

 I think a lot of the problems with peeling clearcoat is the timing when applying the clear. 

[mikelj5S230]

I have had cars with clear coat that sit outside and I have never once seen any peeling.

[cobrajetchris]

The main reason why the original base clear coats delaminate is the factory does not apply enough of it and the clear coat is where all the U.V protection is. Many of the U.S plants apply basically one wet coat and it has enough mil thickness to get it out the door but after a few years it breaks lose from the base coat. I have a Ranger truck I bought new and the finish lasted about 6 years and I repainted in base clear and applied 2 full wet coats and 11 years later it still looks good and has sit outside since day one. Clear coat delamination on vehicles that have been refinished by painters in shops is typically a user error or product failure in my opinion. 

[J_Speegle]

....... Clear coat delamination on vehicles that have been refinished by painters in shops is typically a user error or product failure in my opinion.

Thought it might have to do with  minimum coat then cutting and buffing - as well as environmental issues

[WT8095]

Found an explanation from a former PPG chemist. He replied to a post showing "bubbling" under clearcoat which led to peeling. But he covers multiple causes in his reply, some of which were mentioned here.

Tom, I worked for PPG (Resins and Coatings Division, Automotive OEM and Refinish) for 16 years, starting out as a chemist and ending up in sales. That said, I'll tell you a few of the causes for the problems you showed us.

Number one: Extreme temperature variations cause delamination between the clearcoat and the basecoat color. This will also rarely happen between the basecoat color and the substrate primer. Basically the clearcoat will expand and contract at a different rate than the basecoat color in extreme heat or cold. It actually happens more often on areas of the car where snow, ice, or frost accumulate. It can also be accelerated in areas that are subsequently heated quickly, such as a hood over the engine.

Number two: Acid Rain, as previously mentioned penetrates the clearcoat surface and breaks down the chemical bond between the clearcoat and the basecoat color. Again, this will cause a delamination between the layers since once the chemical bond is destroyed, only the weaker mechanical bond remains. Like the above reason, usually occurs predominately on top surfaces for obvious reasons.

Number three: More likely on repaints...recoat sensitivity, or not enough dry time either between the basecoat color coats and the clearcoat or not enough flash time between coats of clear. Again, unlikely on OEM and will usually show up much sooner in the form of "solvent popping".

Number four: Poor compatibility between the clearcoat and the basecoat color. I would think Dodge would know better than to do this but I've seen it on OEM before. You can't just put any clear over any substrate. In the old days when I first started, guys used to try to put acrylics over laquer (). The acrylics were usually much "hotter" and would dissolve the laquer under them. It can be done but usually with an intermediary barrier coat.

Number five: Insufficient clearcoat applied (or even some has been removed by color sanding or buffing) causing the clearcoat to provide a poor UV and chemical barrier. In the late 80s and early 90s the Big 3 were big offenders of this one. They were only allowed to spray a certain quantity of VOCs so rather than paint less cars, they just used less clearcoat on the same number of cars. We all remember the cars and especially trucks running around with paint peeling off back then. Well, there wasn't enough clearcoat or even colorcoat UV and chemical barrier protection to keep the primers from degrading so both the chemical and mechanical bonds were destroyed under the topcoats. It's like leaving something primered and never painting it. After a while the primer looks like chalk. This is another unlikely scenario based on the pictures you posted.

Number six: Poor waterbourne technology. Again, based on the VOC regulations of the time, auto manufacturers used a significant amount of waterbourne materials. Unfortunately, the technology was not very advanced at the time and the protection provided by these materials was substandard at best. Just about anything would penetrate these clearcoats, including water if left to absorb long enough (e.g. snow pack on the roof or hood). This scenario is also likely, based on the period your car was built.

There are a few other possible causes as well, but I could go on forever and a couple of these are most likely.

The bottom line is, the only fix is to sand it down (no chemical stripping) or media blast it off and repaint.

Good luck, hope this helps.

Source: http://www.meguiarsonline.com/forums/showthread.php?29024-Examples-of-clearcoat-failure-and-an-explanation-of-possible-causes

[Bossman963]

I just got done doing my 70 B302 in Grabber blue and its a single stage in DCC acrylic urethane paint and if u really want that super deep look , you can also clear coat it. You can color sand & buff out single stage if desired.

Using a solid color I would use single stage as others have stated, its easier to blend if needded on a repair ( yes it takes an experienced painter) the 2 stage water paint base is junk- the reason they use  the water base paint as its super easy to blend paint.

Look at all these cars on the road that have clear coat coming off on the roof line, 1/4, deck lids, hoods etc they all are 2 stage water based paint.

PPG makes a very good product and in acrylic or enamel base paints with the correct hardners.

Below is pics of my 70 B302

[PetesPonies]

There is a chemical bond between base color and clear coat. When that bond is broken down, it will peel. Or if the proper bond never happened. This has happened with OEM finishes as the factories try to do things faster and cheaper. You all have seen cars with peeling clear that have never been repaint. All the manufacturers have experienced this over the years. With all that being said, a SS urethane solid color can look just as good as a BC/CC IMO. Urethane is durable, you can cut and buff just as BC/CC. If some shop is pushing you one way or another, it is not because they are looking out for what you want. It is purely for them.