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Mike / Vantaaj, I am much impressed with your detailed explanation of paints available today and their pros and cons. I've certainly printed out your opus and will carefully file. I'll be the first to admit when someone gives detailed information and makes it available to "the public" it is always open to interpretation and differing opinions. My only minor comment is there being no mention as to how important color sanding and polishing is to either single or two stage paints. Except for painting numerous wheels metallic silver then clear coating, I have little knowledge of the two stage system. I've been introduced to a local fellow who fabricates / restores / paints hotrods and since most all have at least two or more colors (as in flames, etc) he clear coats with up to eight coats with color sanding between every few coats. Most feel it isn't necessary to color sand or polish clear coat, but if one is looking for that deep shine, it is a must. Will add his minimum paint job is $13K.

I use only single stage and spend myriad hours color sanding and polishing the car.

I add this only in that most who are unknowledgeable with the process, don't realize how important this portion of the paint process is. Most inexpensive paint jobs use an inexpensive enamel and just enough paint is applied to get a nice over all shine. To do this and to avoid orange peel, the thinner the paint the better.

Biba
 

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Two stage paint issues and questions

This is my first entire painting of a car in 2 stage. I've painted numerous 2-stage wheels. My major concern, at the moment, is issues (aka bugs) in the clear coat. On the enclosed photo of an area on the front of the hood, the issue on the left is a major divot caused by partially removing a bug on the second of three coats of clear. The one on the right is an embedded bug on the final coat but goes down pretty deep (I did a bit of scratching after taking the photo).

The color is the Alfa medium silver metallic. For now the clear has been color sanded with 1000. I've spotted in (after drying) small divots in single stage paint and it works fine. I assume I can do the same with clear? Any other suggestions - short of repainting - especially if it is a sure fire way to get rid of embedded bugs?

Though it is pretty faint, I have an area on the front cowling which bothers me. If I respray the panel, I'm concerned that where I join the fenders (I cannot blend to save my life) the paint thickness will be at different levels.

Except for bugs in the clear and the tedium of spraying six coats, I really like 2-stage. I was amazed that after final polishing scratches were simply not a problem.

One more question: To get a deeper shine, do any of you spray three additional clear coats after sanding down the original three? Is it worth it?

Biba
 

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Painting over filler

I've just started sanding the primer which is to hopefully be the final one before completely painting the shell of a 750 Spider with a guide coat. I'm finding I'm sanding through to filler on about 5% of each fender.

Unless other's feel differently my plan is to simply give a quick coat of paint over the filler parts, then paint one fairly heavy coat over the entire shell.

If I spot primer the filler spots, I then have to re-sand the entire shell because of the overspray.

Since this is the guide coat I am somewhat concerned if the filler will take the paint differently from the primer so it ends up looking mottled.

It will then get another coat of primer before the final painting so won't affect it.

Biba
 

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Paint polishing problems

I try to wait at least two weeks after painting - generally longer - before I color sand and polish single stage paint. However, in the past couple of years I've had problems with unevenness in the surface after polishing. I mostly use 3M's foam polishing pads. I polish at 1800 rpm, keep the pad moving, and also keep it mostly flat. I'll add that I don't polish until all of the, umm, surface irregularities have been color sanded off and finish with 3M 2500. I use the easily adjustable thumb wheel rpm-wise Makita polisher.

Do these pads get stiff after multiple uses? The 3M pads are somewhat stiff when new. I'm not opposed to replacing them, but only if that is the problem. I'll add that I'm anal about washing and spinning the water off after each use. I use both flat and the rounded types.

To phrase all of this another way, I'm trying to figure out if the problem is my polishing technique or the tools I use. Or both.

Suggestions, comments welcomed.
 
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