urethane paint ?

[PC]

Isn't the problem "orange peel" below the clear coat? Isn't it the paint itself. I'm confused ...

I have no idea where it comes from, but there's a very common misconception that the color coat is "paint" but the clear coat somehow isn't.

The clear coat goes on liquid and hardens to a solid protective film. That's practically a definition of "paint" isn't it? How can "paint" only be the thing that goes underneath that?

They're both "paint!" One just happens to be pigmented and the other isn't.

Or try looking at it this way, <span style="font-style: italic">neither </span>is "paint." Each one is half of "paint."

The coatings industry doesn't call any of them "paint." The word is so vague and can have so many meanings that it's effectively meaningless.

They talk of top coats, base coats, filler coats, adhesion coats, e-coats, conversion coats, this coat, that coat...

They're all "paint."

Confusion comes when people assign labels and then associate characteristics with those labels rather than looking for the unique, individual characteristics of each component.


Thank you. We now return you to your regularly scheduled thread.



pc.

 

[KVH]

Here was someone else's comment on this same subject:

Not an experienced painter but what else but elbow grease and fine wet paper. Surely you don't want to clear coat it?

The question is whether the orange peel showed up for Mtlman before he applied his top coat, finish coat, or whatever it's called. If the base coat appears to have an orange peel texture wouldn't one address the issue right then and there?

Not a body or paint guy here.

 

[PC]

Yes, if there was orange peel in the base coat of a two stage system then it would need to be addressed before shooting the top coat.

That rarely happens these days because dedicated base coats shoot flat, without gloss or peel. But like any other flat paint, you can't sand it and get the same surface.

So if there's a drip, dust inclusion or other such defect in the base you need to sand it out and re-shoot the area. (as Hondo mentioned)

If you shoot a single stage finish the color coat is the top coat and you will get the gloss and peel. In that case you would be sanding the color coat.

<span style="font-weight: bold">mtlman8</span> didn't say where he is in the process, or whether it was single stage or base/clear, only that he had peel he didn't want. Right or wrong, we assumed he had shot it correctly and was at the appropriate step.


pc.

 

[CJD]

Here is an excert from the Jaguar body and paint manual. It won't help now that you have it, but it does give a good insight into causes and basic fixes. Funny, they make the "re-spray" option sound easy!?!



S7.5.23 ORANGE PEEL

Alternative Terminology: Pebbling, Poor
flow, Poor leveling

DESCRIPTION
A paint finish which has an undulated surface
resembling an orange skin. Impaired reflective
ability is characteristic of this defect.

WARRANTY RELATED CAUSE
&#56256;&#56320; Not a warranty defect.

NON–WARRANTY RELATED CAUSE(S)
a. Spraying over contaminated surface.
b. Using incorrect or inferior thinner. Insufficient
thinning of color.
c. Air pressure too high.
d. Incorrect adjustment of spray gun.
e. Incorrect spray gun technique. Gun held too far
from or too close to surface.
f. Spraying in draught or high velocity air extraction.
g. Air or metal temperatures too cold.
h. Defective spraying equipment.

PREVENTION
a. Clean surface thoroughly ensuring it is free of
wax, oil and silicone.
b. Use thinner as recommended by paint
manufacturer.
c. Ensure proper spray atomization with minimum
air pressure.
d. Clean and adjust spray gun.
e. Use correct spray gun technique.
f. Prevent draughts and ensure air movement is not
excessive.
g. Ensure correct temperatures of paint and
surroundings.
h. Ensure equipment is in good condition.
Compressor, air transformer and lines should be
regularly serviced.

COMMENTS
a. When color has hardened, fine wet flat, compound
and polish.
b. If condition is very bad, wet flat with fine grit
paper and re–spray

 

[KVH]

Very interesting and helpful.

Just to keep the thread going a bit, what about a "hand rubbed lacquer finish"?

I have no idea what that is, but a guy with a TR4 once told me that's what he wanted.

Any thoughts on that v.s. urethane?

 

[tdskip]

Lacquer is just another paint formulation. EPA requirements have resulted in paint formulation changes so not sure how readily available the old school lacquer even is anymore.

 

[PC]

You can still get automotive lacquer, just not around here (or other areas with strict environmental controls).

I remember back when the rules first hit the SCAQMD controlled zone. A huge bunch of the custom painters moved out to Victorville and North San Diego County. Then they moved out of state entirely.

For a while you saw guys shipping cars out of state to be painted or smuggling in contraband paint for clandestine custom shoots.

Eventually, everybody figured out how to use the new stuff and nobody cared about lacquer anymore.

I guess there's still a call for it for the few folks who demand period correct and those that never accepted a world without Elvis.

Other than being way more prone to fading, chipping, cracking, crazing, scratching, etching, flaking, swirling, pitting, smearing and melting, lacquer is easy to work on. Which is handy because you <span style="font-style: italic">have to</span>. It lays down sort of semi-gloss and needs to be sanded and buffed.



pc.

 

[CJD]

The "hand rubbed" is sorta what this thread has been beating around.

The laquer was designed to dry VERY fast, so there would be less time for contamination to stick...back when paint booths were not as good as today...and a lot of painting was done in open air. It went on very thin, and flashed in minutes, so it took many sprays to cover and give decent build. Orange peal was much easier to get when a lot of coats of laquer were sprayed...like 6 to 12. Then, it could be hand sanded with fine grit and hand or power polished to a mirror finish.

It was from an era of cheap labor and no EPA. It was the standard for about a century...

I used to think hand rubbed lacquer was the cat's meow...but, once I sprayed my first good 2 part urethane...I never looked back! A laquer finish lasts 2-5 years in the sun. Urethane just keeps going...