Tips for painting metallics

ksungela

ksungela

Member
I've painted all of 3 cars, all solid colors, and am now doing my first metallic. '66 Corvette Nassau Blue. I've gotten some advise from Barry about shooting the base, but thought others would benefit from a discussion on what do to different when spraying metallic base vs.a solid. I'm using Wanda and a LPH400.
My plan was to spray the base while the car was apart, but it sounds like i'm risking poor color matching panel to panel. Barry suggested painting 2 coats with it apart, hanging all panels on the car, then shooting a final coat so everything blends. My only concern is will the overspray through the door, hood, and decklid gaps create a dry spray finish in the jams and if so, how do I fix it, light sanding?
Would applying the final coat of base with the doors, hood, etc. not mounted on the body, but oriented in the final position (hood laid flat and the doors upright) and sprayed at the same time as the body be a viable alternative? This would eliminate any jam issues.
What's the recoat window of Wanda base?
What's the window from final base coat to the first Universal clear coat?
Thanks for your input.
 
If you can spray all the panels at the same time and with same coats it will be a much better job with no dry edges. I let Wanda sit over night then clear lets all the tail solvents out. I would not say spray body and clear then do the other panels a week later or at another time as then the color may be off.
 
I applied three coats of base with everything apart (orientation not important), waited till it flashed off real good and could be handled, hung all the panels and did a fourth coat. let sit over night, rehung the panels and cleared everything the next day. The little over spray you get when you do the fourth coat isn't noticeable since you'll be applying within the re coat window and it melts into what you just sprayed (you can't sand it anyway, it will mess up the appearance of the metallic).

See this post:
http://www.spiuserforum.com/forum/sh...4584#post54584
 
Arrowhead;n81476 said:
I applied three coats of base with everything apart (orientation not important), waited till it flashed off real good and could be handled, hung all the panels and did a fourth coat. let sit over night, rehung the panels and cleared everything the next day. The little over spray you get when you do the fourth coat isn't noticeable since you'll be applying withing the re coat window and it melts into what you just sprayed (you can;t sand it anyway, it will mess up the appearance of the metallic).

See this post:
http://www.spiuserforum.com/forum/sh...4584#post54584
Click to expand...

I have some questions on re-assembling the car to do the 4th coat. After you spray 3 coats of base on say different days, different weeks, and you let it dry.
Doesn't that mar up the base when you blow it apart then assemble it for the 4th coat?. How do you get ALL the oils (from your hands) out of the base before you do the 4th coat. Then, you have to take the car apart again to clear coat it. That is more handling, more oils in the base. rinse repeat.

How about a thin coat of clear after the 3rd coat of base? That seems like it would be easier to clean up finger oils.
Then, after the 4th coat of base on the assembled car, spray another thin coat of clear to protect panels from smudges while you blow it apart again for final clear coats.
Am I over thinking this?
Would it effect the look of the final job to add a layer of clear between the 3rd and 4th coat of base?

Danford1

PS I just had another thought. Rather than spray a thin layer of clear after the 3rd base coat. How about mixing the clear and base together when you spray the 3rd coat of base?
 
Well I've been using PPG and there's only a 24 hour recoat window and that's why the clear need to be applied the next day. So technically, the clear needs to be applied within that window so it it has to be planned out so it can all be done in one shot. I (and any helpers) use disposable rubber gloves when handling any parts to prevent any contamination. I tape up any surfaces that could be damaged when assembling in base coat like where hinges bolt up. Yes, it's definitely a PIA and it might not work with all projects, but I think you end up a with a much nicer final result and less fussing with masking. If you don't have the room to do everything at once, this might not work for you.

I'd stay away from clearing between coats or mixing base and clear for a third coat. Yes, you might be over thinking this a bit. When the base coat is fully flashed, you can handle it with gloved hands no problem. If you've that concerned, a quick gentle wipe down with water based W&G removal is all you would need.
 
Yeah, the 24 hour recoat window will screw me. What I think I'll do is paint all the jams and edges of the doors, fenders,cowl vent, valance panel and under side of hood and deck lid plus add a coat of clear to them.
Let that dry Then assemble the car and spray the base on all at one time. I can add a coat of clear to protect it all. Let that dry then blow it apart and clear all the parts separately. That way I'm not having to try to seal off all margins trying to keep the over spray from messing up the jams. The jams will get more clear the same time as the rest of the body structure. I think that will hide the over spray...

Danford1

PS I thought I read somewhere else where Barry said not to use water based W&G remover on base coat, you should use solvent based W&G remover. Water base might eat into the base coat.
 
Do you spray the final coat any differently than the previous ones when the panels are all on the car. For example, do you hold the gun any farther away from the panel?
 
Jorge M.;n81571 said:
The 700-1 will mess up the basecoat for sure, use the solvent based one instead.
Click to expand...

Fair enough, maybe because I use PPG DBC with activator, it's not damaged by the water base?
 
Arrowhead;n81732 said:
Fair enough, maybe because I use PPG DBC with activator, it's not damaged by the water base?
Click to expand...

I've always gotten white streaks or smudge marks when using the spi waterborne on base, activated or not. So I stick with the solvent one if it needs cleaning.

I think I have read that Jim C uses the aerosol glass cleaner like Sprayway on basecoat with great results, very mild product but still cleans up well.
 
I was reading about Sprayway glass cleaner and their website says"Contains perfume-grade alcohol for best performance".
So... if the SPI wated based W&G has an alcohol base and you have to let it dry for 45 minutes, do you also have to let the Sprayway cleaned surface dry 45 minutes?
As you can probably tell from reading all of my posts, this 45 minute wait time is a big deal to me. I'm trying to find a way around it every time I use SPI water based W&G ...

Thanks
Danford1
 
If your goal is to remove possible organics that a solvent base usually doesn't (re: finger prints or other body oils), 90% or greater isopropyl alcohol works great and it evaporates very fast and leaves no streaks.
 
danford1 said:
Yeah, the 24 hour recoat window will screw me. What I think I'll do is paint all the jams and edges of the doors, fenders,cowl vent, valance panel and under side of hood and deck lid plus add a coat of clear to them.
Let that dry Then assemble the car and spray the base on all at one time. I can add a coat of clear to protect it all. Let that dry then blow it apart and clear all the parts separately. That way I'm not having to try to seal off all margins trying to keep the over spray from messing up the jams. The jams will get more clear the same time as the rest of the body structure. I think that will hide the over spray...

Danford1

PS I thought I read somewhere else where Barry said not to use water based W&G remover on base coat, you should use solvent based W&G remover. Water base might eat into the base coat.
Click to expand...
I prefer not to wipe the base with any sort of cleaner as well. Shouldn't be any need at this point.
 
I don't think I have ever waited that long with 700-1. The 45 mins time will buy you a safety margin when dealing with bare metal because of being porous.

Once you're at the primer stages a bit of air blowing over the panel should cut the waiting time considerably.

I hope I'm not giving bad advice here, just going from what I see every day in body shops and personal use of the waterborne cleaner.
 
I understand where many of you are coming from with wiping the base after handling it, however it has always been something that has scared me, although, I have not had any reason to do so. To me a solvent cleaner seems like it could soften things up, and or introduce more solvents into the base that are not necessary, and a waterbourne cleaner could potentially soak into the base as well. I know you can do a lot and get away with a lot but I didn't see any reason to wipe it, therefore I don't.

Also. I have no idea if your situation allows for this but a method I like do do is this. I paint the shell of the car, doors and fenders at the same time apart in my booth. If you have enough room this is ideal, that way you are baseing everything you see from the side at the same time, same amount of coats, etc etc, so when you bolt it together you should be good as far as color match is concerned, then i will paint the hood, trunk, bumpers etc etc in another session. theory is that if there is a issue it would be from hood to fender and easier to deal with and harder to see.

I have also done a few projects where I would paint the shell and doors at the same time and fenders with the other pieces later, My thought there was if there was a color match issue it would be between the doors and fenders and then i could assemble the car, and repaint those panels and blend them together, It's also easier to tape those panels to avoid tape lines, so it's the lesser of evils.

I also have to admit that I always worry about this when i paint a car apart, and as long as there is enough color on the car I have never had a issue.

Knowing that I tend to apply more base than a lot of people. I apply base until it is completely covered. then i let it dry for a fair amount of time and then lightly scuff sand it and apply two more coats, the theory behind that is that I am first focused on coverage. When it's covered I then scuff sand it to make sure there is no trash in the paint, and then I apply two more coats only worrying about orientation and color consistency. This method has worked very well for me over the years. However I tend to feel that this means you end up with a extra coat or two of base coat on the project when finished, but I have been bit and not had enough before as well, Once again, lesser of two evils..
 
Chad, what do you use to clean the base after you scuff sand it?

Danford1
 
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