Are COB paints suited to our climate?

[Calaber]

In the area around me, many cars with metallic paints have massive sun cancers, with all horizontal surfaces suffering heavy peeling of the clear coats. A lot of these cars are not very old, perhaps 05/06 models or even later. All makes. It strikes me that COB isn't as durable in extreme hot areas as the old acrylics. Am I right?

 

[Drawnnite]

Cannot answer your question but the panelbeater I had a chat to about the sun damage on mine explained it pretty well.
Basically you need to treat your cars paint the same as you would your skin with the sun.
That means making sure you have a coating on top of the paint to help protect it, the same as how you would apply sunscreen when you go outside.
So maybe its not a case of the paints not being suitable but the harsh conditions need to have preventative maintenance to ensure that they can withstand the conditions they face.

 

[EYY]

Some colours are more susceptible than others. Reds, oranges and yellows are the worst - it’s just the nature of the paint. These colours used to have lead in them which meant they were more vibrant and durable.

Modern 2 pack paints will long outlast old acrylic paints - but preparation is key. Plenty of cars out there with original paint doing fine.

As mentioned above, paint has pores. These pores should be filled in with wax to protect the surface and prevent contaminants getting beneath the surface of the paint.

 

[figjam]

I would say that they are not as durable as the old enamel paint.
Older cars were held together by their paint, until a big chunk of good paint fell off attached to rust, leaving a hole.
Now, the paint disappears, and the car rusts from the outside.

 

[Calaber]

Older paint didn't peel like clear coats do. I had an HT which was ten years old painted in metallic acrylic from the factory. I looked after it but the factory paint held up well without any sign of deteriorstion

There might be plenty of cars running around with the COB lasting but in my area, the cars are generally decrepit once they reach about ten years of age. IMO, COB requires a lot more care and regular waxing that the older paints.

 

[EYY]

Nitrocellulose and acrylic paints are different.

Much of the ‘good’ stuff in paints were removed in the 80’s and 90’s. These older generation paints are no match for modern iso based 2 pack paints, COB or otherwise.

 

[WazzaVN]

Yeah like eyy says it took allot of the guts out when the lead was removed. Also modern cars only have 1 and a half coats of clear any resprayed car with 3 or so coats will last longer. Wax is important too not just for sun but for other things that can land on your paint and start to slowly eat at it.

 

[Calaber]

So, it's the thinness of the paint coats, rather than the durability of the materials used, that leads to the clear coat breaking down? How is it then that "solid" colours like white don't suffer the same problem? I imagine they aren't COB. And I think my original point remains. From what I see every day in significant numbers are late model cars with absolutely ratshit paintwork, yet older cars, with acrylic paintwork, are merely faded which could be revived with polishing. Modern paints might potentially be more durable but the way they're applied clearly isn't good enough to withstand continued exposure to our hot climate.

 

[losh1971]

I think some of it comes down to the colour. White seems to withstand anything. Where as say red becomes thin very quickly especially acrylic. Not sure how true this is, but I have heard they put white on thicker because it doesn't cover real well other wise. The old acrylic clear coat wasn't great AFAIK. It tended to crack up (crows feet) a bit from too much sun.
This is pure speculation but if paint peels after 6 - 7 years gotta wonder if they are giving it enough coats to get through warranty but at the same time cutting costs????

 

[Drawnnite]

The old mans VZ Wagon is white. It doesn't have a clear. Which is what the Panelbeater I spoke to who explained the sunscreen analogy told me is how it was from factory. Its also why the white looks chalky if it hasn't been waxed.

It was also explained that the more you wash it, the more you should also wax it as washing will actually remove some of the protection.

Would say that, a bit like asbestos, old school paints were considered a great product in their time, its only a while later they realised the impact it was having and unfortunately had to remove it, and as such techniques and materials had to change in conjunction with the removal of the good stuff.