This question came up on our supra list and we have a memeber that is a professional painter here is his response:
Like I've said, the thing about waiting for fresh paint to cure before
waxing is so you can let the paint cure - simple. But the *actual* reason
David is looking for is this:
"Curing" is the action of paint "breathing", not just drying (they are one-in-the-same really). "Breathing" refers to the solvents literally evaporating from the paint. This evaporation needs to occur properly to avoid "solvent popping".
Solvent popping is NOT something you want to cause. Otherwise, you run a high risk of needing one of two things for a solution/fix: 1) a tedious/risky/professional buff job that will NOT help in *major* cases,
or
2) a RE-paint.
Usually (like 80-100% of the time), if the paint is gonna pop, it's gonna do it soon (next 1 to several hours) after it's been painted, and only
because of human (painter) error. Solvent popping is what happens when the solvents (the reducers and activators) can't escape safely through evaporation. If evaporation is affected in a negative way, the solvents literally get trapped in the paint (this can happen in primers and clears) and have nowhere to go except THROUGH the clearcoat, (or primer surface). When the
solvents get trapped and force themselves out (because they are coming out no matter what!!), they come through the clear leaving very tiny HOLES. These thousands/millions of remaining holes are the sites of solvents busting through to open air. They are extremely tiny, yet obvious up close because of their number.
Causes of solvent pop - (usually occurs during hot months):
1)The painter sprays the clear too thick and the exterior surface of the clear skins over faster than the paint can breath...trapping the solvents.
2)The car is not left in the spraybooth long enough (at least 1/2hr to 45min) for the booth to finish pulling (with it's air draft) the solvents out as they are evaporating.
3)The car is pulled out from the booth too early, and the draft in the shop may cause the paint to skin too fast and pop the paint (somewhat common with sensitive clear brands).
4)The paint is left to dry properly for a short time (couple hours or
more), but then rushed into the hot sun causing popping anyway.
5)The painter mixes the clearcoat in the summer with a reducer that is designed for the winter...because he needs the paint to dry faster. This is a gamble depending on the temp. range of the reducer. There are several reducers a painter can choose from. "Hot" reducer drys paint slower, "Cold" reducer drys paint faster....all to compensate for weather changes.
Basically, popping is caused by *anything* that skins over the paint too
soon....faster than evaporation.
After the paint is dry and the car is deliverable to the owner, popping is not nearly as sensitive to popping, but I suppose it is still possible especially if it's summer time. ***Some paints are more sensitive to popping than others***. There is no set rule stating that paint WILL pop if waxed...this is why painters who don't want to do a job twice, will simply say "just dont wax it for a month or so". Waxes are feared because they act
as a layer...a layer that might/maybe/could (but usually won't) trap solvents. It really all depends on the paint brand, how soon after the paint was sprayed and outside temps. Some paints are more abusable (like Dupont) than others and will stand up against thick spraying techniques and force drying methods....others will bite you in the *** and pop easy (like
SHERWIN WILLIAMS, aka MARTIN SENOUR) <------try avoiding ! I sprayed thats stuff for my first 4yrs and it's not exactly good stuff.
Since curing takes mainly 1-2 months (sooner during hot and/or less humid months), it's just easier to tell customers to avoid waxing for that long, rather than have to explain everything that I'm writting here
Zaino is really the only polish that would threaten me right after
painting since it seems to bond so well and for so much longer than other crap wax (plus zaino says it builds coats). I painted my car last month and I still haven't zainoed it (only sanded and compounded it so far). In the meantime, compounds for some reason don't skin like waxes etc. For popping, I
believe
it has to do with the brand of wax/polish as with the brand of paint.
>
> Hope that explains it all...