March 31, 2015 at 5:43 am #48547
Hi everyone was wondering if anyone could help explain why color on bumpers can be different than the fenders even when I blend into them with the exact same paint? I am using envirobase ppg. I have a great bumper stand that allows me to paint the bumper the same way it sits on the car so my paint pattern is the same from the bumper to fender. I have herd that it is because one is plastic and one is metal but if I seal both it seems like the paint has the same surface to go on. And dose that make my spray out cards off too because there made of paper? Would really like some help on this one even my paint supplier can’t give me a solid answer. Thanks Jamin J ☺March 31, 2015 at 6:39 am #48548
Bumper colors can be off because the angle that they sit on the car. Take a sprayout card, seal color and clear. Let it dry then turn it face down use a straight edge and pen and firmly draw a line across the back side. Look at it in the sun. Most of the time it will be 2 “different” colors. This is a good way to show a customer “why” their bumper doesnt match. Also plastic holds static which can affect the way the pigment lay down.March 31, 2015 at 6:47 am #48550
Very true about the angle thanks for the good adviseMarch 31, 2015 at 7:01 am #48551
Also the static makes perfect since even though I alcohol prep it and try to tack rag it lightly I’m sure there’s still a little static there thanks again Jamin JMarch 31, 2015 at 7:43 am #48552
So, when you paint a bar off the car, by turning it around it will be the same colour?
Nah, static, sure, but you should have that under control. What makes a colour different on plastic to metal is the way that the two different substrates absorb heat. Despite being in the same booth, at the same time, they will be at different temperatures. So, when the paint is sprayed on it will take marginally longer to flash off the plastic than the metal, generally resulting in the plastic looking a little darker than the metal.
Obviously, this is different to ex factory where the two parts may have been painted in different factories, sometimes months apart and using different paint, both brand and technology. It’s a wonder they get them even as close as they do.March 31, 2015 at 8:04 am #48553
Interesting kinda wanna take my thermo pointer and check that out thanks for that infoMarch 31, 2015 at 1:21 pm #48557
Bumper to car paint even when using the same paint on both car a and bumper can also be attributed to the drying characteristics
For example, the evaporation rate for paint varies over metal or plastic. A longer rate gives the flake pigment additional time to “float” and can
darken the face tone of the colourApril 1, 2015 at 1:42 am #48563
Hi I no nothing about painting that’s why i’m here, trying to learn, the replies to this topic basically says no matter what the paint on the bumper is going to look darker because of it being plastic, can’t the problem be solved by lightening the color before it goes on the bumper? just askingApril 1, 2015 at 3:34 am #48564
Plastic and metal also absorb and reflect light differently.April 1, 2015 at 3:57 am #48566
I know that’s why they were saying the plastic bumper would look a little darker then the metal fender and that’s why I asked if it would solve that problem if you lighten the paint just slightly to match, it don’t hurt to ask like I said I don’t know the first thing about painting i’m here to ask questions and try to learnApril 1, 2015 at 8:16 am #48567
Yes ur right lighting a color that is too dark will solve that but I wanted to do some investigating on why and if my spray outs will give me an accurate match since they are a different material than metal and bumpers I spend sometimes more time on spray outs getting the color as perfect as I can than doing the actual job and being in a production shop I need all the short cuts I can get I’m an intermediate painter so speed is not there quiet yet but I know if I learn the right way it will come in time. Thanks for replying and keep on painting its a blast and very rewarding ☺April 1, 2015 at 12:58 pm #48569
[quote=”janedoe” post=37016]I know that’s why they were saying the plastic bumper would look a little darker then the metal fender and that’s why I asked if it would solve that problem if you lighten the paint just slightly to match, it don’t hurt to ask like I said I don’t know the first thing about painting i’m here to ask questions and try to learn[/quote]
Yes, lightening the colour would, maybe, work. The problem is that you don’t know how much the difference will be, so you may overcompensate and that would look even worse. Of course, if painting on the car then you’d need to paint the two areas separately and in any kind of production shop there just isn’t time for that.
If I think that there may be a difference (sometimes you can see it in the base coat) then I’ll put a drop coat over the end of the bar so the flake sits up a bit more. Usually that’s enough. The problem becomes worse with heavy coats or too many coats, so you need to watch that, too.
You often see differences ex factory but I was looking today at a Mazda 6 in that new red which uses a tinted clear. The difference, on a brand new car, was, to me, unacceptable, but it was good enough for the factory.
Sometimes we make a rod for our own backs by worrying about things that the customer can’t even see.April 1, 2015 at 7:52 pm #48572
ok I get it now thanks for that inputApril 2, 2015 at 5:54 am #48574
I forgot about the temperature difference. Yes that has an affect on color. As far as lightening that can affect either the face or the pitch. Get the face to go one way and the pitch will go the other. Vice versa. Sometimes a different alternate can get you closer. We have gotten to where we will have the body tech cut a corner off the bumper. Mask off half.Prep it same as the new bumper. Use that as s spray-out. You can snap it onto the car and verify your color. Its quicker and easier to mix a different alternate or tint on that than respraying a whole bumper. Mask off the previous color before applying the new to see which direction you are going.April 17, 2015 at 11:37 pm #48645
most people don’t look at how the bumper didn’t match when the car is new, they only look after the repair is done.
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