Ground coats
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[quote]If the groundcoat is making a difference, there’s not enough paint on it.[/quote]
Very true. With a sealer, you’ll also have better color hold out (or should).
But at $2500 anything is possible!
What about spraying silver?
I plan to sand the cheap primer off the bumper, adhesion promoter, Dupont epoxy primer/sealer, sand with 800 next week and shoot bc/cc. The primer is gray btw.
Good enough? :blush:
you’re good zarbat007!
OK, what does “zarbat007” mean? 🙂
There’s a reason to use “spray-out cards”…..to get total hiding.
That’s the right way to do it, not relying on the undercoat for the final color.
That’s why mfg’s recommend them.
It usually only takes another coat or two.
If you don’t do it that way, then future repairs will never match because anywhere
you add a coat over the existing paint, it will be different.
I don’t do overalls so it’s not an issue for me to save a little paint,
I always have paint left over on my collision repairs.
I had one car overall (15 yrs ago)that I didn’t get enough paint on, couldn’t
see it untill it was out in the sun, never again will I risk that. B)Mfg’s also recommend ground coats JC.
In the case of some red’s & yellows their can be a difference of 5 coats in my paint line.Ground coats are important when matching oem paint as well. Some of those transparent colors are not sprayed to true hiding by the manufacturer. they rely on the ground coat color for coverage and when doing a repair if you dont use the same shade ground coat your color wont match. Completely understand what you are saying about true hiding JC but with some of these colors true hiding will create a mismatch when trying to match that oem paint.
In BK’s case since he is doing a complete and not trying to match anything it wont matter so much. if he keeps track of what he uses he can repair it simply enough in the future[b]Han wrote:[/b]
[quote]
OK, what does “zarbat007” mean? :)[/quote]:lol1
It has no real meaning, I thought of it when I was about 16 or so and couldn’t think of a decent SN for Yahoo Messenger. :blush: :silly: :wak
Something to think about Jim since you do collision work bro.. Maybe u should be looking into the groundcoats a little more ole buddy.. Could make blends allot easier 😉
You guys may remember this car I did a complete on a while ago (my mothers car):
[img]http://img441.imageshack.us/img441/3715/dsc00700jpgvy2.jpg[/img]
On the rocker moldings I had used a dark undercoat, i think someone else had some mixed up so I said what the hell I’ll use it instead of mixing my own. I didn’t use a ground coat when it came time to paint, it honestly took about 10 coats to cover that black. I was around 5 for the rest of the car using a light gray in parts, original paint in others.
And this is BASF paint, its made to cover quick!
Anytime you do a repair where you blend, you stop the ground coat short
of the paint area. You can’t spray primer right to the same edge as where the color stops,
you have to spray past that to gradually blend the color.
That’s more color over existing color.
If an additional color coat changes the color because the existing paint has the
color affected by what’s underneath, it’s impossible to get a true match with new paint
because the blend area will have more color coats.
Aside from Dupont, most paint companies make their paint to match what is
actually on the car with only their base,and if you don’t get enough coats it won’t match.
Why else would they suggest spray out cards? they want you to achieve total hiding
to get a true match.On some colors BASF will have a ground coat or tell you to use tinted primer to get better coverage.. For example I just finished a transparent red pearl that had I not used the ground coat would of taken 6-8 coats to cover, where as with the ground coat it only took 3.. I could prove that on a spray out card to, and in the end the color will match. Ultimately with enough coats yes you will get coverage and color match. But I am all for saving money and time and a good ground coat or tinted primer will do both..
Cool,
A true 101 controversy. JC has a great point. true coverage is true coverage. But you can get a good match with gray shade undercoats and save materials in doing so. It’s not only dupont that doing it either. Just about every paint company has come out with grey scale primers. Getting a good color match is sometimes more about illusion than having the exact color. thats why we blend. to step out the diff in color so it wont be noticeable. Stepping out a blend on a transparent color is not going to change the shade any more than using a color with good coverage.
Three stage paints look different with more coats of mid coat over them yet you can blend out a three stage color and without having it noticeable. so transparent yellow or reds or any other color that can be affected by the ground coat color can be blended out just fine without affecting the final color matchI’m not used to this here, people aren’t agreeing! what do we do? :woohoo:
[quote]I’m not used to this here, people aren’t agreeing! what do we do? [/quote]
This is a good thing.
On the 73′ Datsun i worked on, i got full hiding in 4-5 coats with Chromabase shooting over primer
and epoxy sealer on the valance panel. Didn’t expect this at all…I’ve only shot yellow a few times (under 5). And maybe about a dozen metallic reds; i used the main red
in the formula (slightly adjusted) for the ground coat and this works for me. I’m sure there are many
other factors involved…You know, thru trial and error I have learned what covers easier and that is what i use.. Im personally not concerned with total hiding of any base.. I just want it to cover and “look as it should”.. Im am concerned with solvents and too many coats of any product 😉
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