[Biba69]

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

 

[aralfa8589]

I'm a little unsure of what you are addressing.
You are sanding through to primer in a few spots. That means they are high spots. Block them down and don't be shy about going way past your defect. Then reprime the repaired areas after masking several inches around the touch-ups. Use plastic sheeting to keep overspray off the car.
Hope this helpsU!

 

[johndewaele]

Painting

Wow, what an education! Thanks so much for sharing this info.

 

[rosso]

Wow. Thanks for a lucid and most valuable explanation of the paint scene. And by the way your corral of machinas is very cool.

 

[Smithy]

Does anyone have experience with the water based paints that serve as a base coat for a bc/cc paint job?

I have been in the automotive paint business for over 20 years and love the waterbase color. It is an improvement over solvent because the coverage is better which allows a thinner paint film to achieve color; this produces a more chip resistant finish. And, when activated, cross links with the clear coat for a better clear to base coat bond. (Dupont, Standox, & Spies Hecker have activated based coats.)

One of my clients refinished his Ferrari in yellow. It took 18 coats of solvent base coat - this is a scary thick film. I am consulting on a Daytona that is going yellow and our shoot outs are giving us coverage in 3 coats. Waterbase base coats are great and are saving painters' arms. These body restorations range from $30,000 to $90,000 and these cars are on the lawn at Pebble Beach. Needless to say I trust the water.

 

[Typhoon90]

I'll add that 2k systems can be sprayed at home, but I wouldn't attempt it if you're a first timer! I do all my own repairs etc at home and have resprayed a couple of cars in 2k in the garage.
I love spraying 2k, it's very, very satisfying to get it just right and not having to buff, but very hard to do at home. I also love teh durability of a 2k system, why put all that effort in and use a cheap paint?
If you've done several resprays or major paint repairs before you should be able to pick it up well.
The key to "backyard" resprays of any kind is cleanliness. Find somewhere enclosed to paint, blow the entire inside of the building down with compressed air several times, wash the walls and floors etc. Then consider waiting for a still morning to paint. Once that hardener goes into 2k, there's no turning back, so pick your day and time well! I also like to take a day off work mid week and paint, very few neighbours to annoy during the week.
I can't stress the importance of cleanliness enough though, because of 2k's relatively slow tack time, it is very sensitive to airborne dust after it has been sprayed and also bugs, who seem attracted to it for some reason.
And with 2k, it really does need some heat to cure in any sort of a reasonable time, below about 20c the cure times slow way down. So you do have to factor that in, don't plan to paint in winter for example!
Personal preference is a big thing, I just like Glasurit, it's a super high quality paint and always goes on well for me. Although I have some PPG clear here which is also very, very nice.
Some of my garage handiwork with 2k, to encourage others that it can be done (yes the green bumper is a bit peely, but it levelled out well as it cured):

 

[Dickson]

Has anyone ever purchased paint from TPC Global? I have access to a compressor, gun, and booth, and am considering painting my car with their acrylic urethane....

Thanks - Dickson

 

[Biba69]

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.

 

[cowfy]

just bought a gtv6 '81 with no rust but..............the top layer of (laquer?) finish is peeling something terrible.is there a definite way of saving the undercoats on this model and just redoing the top shuny stuff?

 

[AFineRide]

So I read this thread with interest but didn't find, or didn't understand what I might be looking for.

I just added a 1981 Mecedes 240D to the garage to keep the younger Alfa company. The 240D has original paint and while most of it is still pretty goods, there some dents that need to be repaired and I'm not keen on panel painting.

In reading some comments on the mercedes forums, it seems that most are recommending an "oil based" paint as opposed to base/clear. Am I confusing paint types with painting processes? Can you do base /clear where the base is "oil based paint" ?

Your comments appreciated...

 

[60sRacer]

I've a MBNZ too - '89 560 SEC in Black. From the 80's MBZ used two different paint types - neither were "Oil Base". They use a two-stage (base-clear) on the metallic colors and a pure single-stage on the solid colors, like black, white, etc. German paints are very good - and very expensive - and readily available in the US.

In California, the older solvent type (probably what they mean by "oil-based") paints are no longer allowed, but the latest water base two-part epoxy paints are wonderful, and lots easier to cleanup.

A two part epoxy, or catalyzed paint, is mixed with a base and a catalyzer just before spraying. Either the base or the clear overcoat of a TWO-STAGE paint, or the color of a SINGLE-STAGE paint can be a two-part epoxy.

Because of air pollution rules, most of them are water-based. These were not so hot when first introduced, but are just fine by now. The old-days version is likely why you see recommendations for the older solvent paints.

Is that confusing enough for you?

Robert

 

[AFineRide]

I've a MBNZ too - '89 560 SEC in Black. From the 80's MBZ used two different paint types - neither were "Oil Base". They use a two-stage (base-clear) on the metallic colors and a pure single-stage on the solid colors, like black, white, etc. German paints are very good - and very expensive - and readily available in the US.


Is that confusing enough for you?

Robert

Uh...no...yeah....

Spoke to three different body shops, non of them the Maaco variety....all them them want to do base / clear with 3-4 coats of high end clear...

I need to find the paint code and see if they can get something like Glasurit or something comparable. I don't want to paint it twice...

 

[AFineRide]

I've a MBNZ too - '89 560 SEC in Black. From the 80's MBZ used two different paint types - neither were "Oil Base". They use a two-stage (base-clear) on the metallic colors and a pure single-stage on the solid colors, like black, white, etc. German paints are very good - and very expensive - and readily available in the US.


Is that confusing enough for you?

Robert

Uh...no...yeah....

Spoke to three different body shops, non of them the Maaco variety....all them them want to do base / clear with 3-4 coats of high end clear...

I need to find the paint code and see if they can get something like Glasurit or something comparable. I don't want to paint it twice...

When I mention Oil based paint, they look at me like I have a third eye..