HowTo – Painting Metalic Paints and Not Leaving Stripes

Tags: Enamel · Lacquer · Paint and Materials · Urethane


http://www.howtopaintcars.com/wp-content/gallery/misc-images/tiger.jpg?i=1458855375Some metallic paints out there are getting out of hand I recently painted a metallic red on a friends ford and when I saw it in full sun the next day all I could think was they must have cut the throat of a MySpace Glitter Unicorn to make this paint.

One of the problems you might run into when painting heavy flake metallic paint is problems with stripes.

If your lighting isn’t that great in your booth or garage you might not even notice that the metallics in your color coat have landed unevenly but once you get some clear on it and get it in the sun you may  want to break out the grinder with 36grit just to stop the ugly.

So, how do you prevent stripes and how do you fix them if you catch it during painting?

What Causes Stripes in Metallic Paint?

The first thing we need to understand is why we get stripes in our metallics.

Basically its nothing more then uneven application of the paint.

If you buy a quart of paint to do an overall paint job and don’t make enough full coat passes you are going to get stripes.

If your gun is clogged and your spray pattern is putting out more paint on one side of the fan then you will get stripes.

If you are painting fast and slow instead of evenly you will end up with stripes.

If you overlap your passes unevenly as you cross a large panel like a hood you are going to get stripes.

The reason that you get stripes is because the Metallics in the Paint are closer to the top of the paint in some areas and closer to the surface / primer in other areas. This happens because the longer the paint is wet during flashing the longer the metallics have to float to the bottom.

How can we cure Metallic stripes in our Paint

Well from the problems above you can see that the only way you can cure these problems is to become a better painter. This doesn’t happen after a handful of jobs it takes many months or even years to pickup on what you are doing wrong while painting and change your style. You can also get someone to train you and scream at you while you’re screwing up but thats easier said then done.

For Pattern problems one thing I have always got use to doing is spraying a test pattern on a piece of cardboard that I tape to the wall in my booth. Yes it would be better to have a substraight that is not porous but its normally what I have around and I am use to it. At least I’m not painting the booth walls.

Test your pattern every time you refill your gun or anytime that you have doubt that your spray cap might be dirty. If you find a problem then stop and clean your gun it will only take a couple minutes.

Controlling your Passes and Overlaps

The next most important thing is to do is learn how to overlap your passes evenly. AND MOST IMPORTANT.. never ever stop in the middle of a pass.

For most paints you want to have a 50% overlap when making passes. If you get to the end of a panel just keep on going and make that last pass as a half on half off pass.

Always paint at the same speed

It can be difficult keeping even speed to your passes when you are reaching out over a hood or walking the whole side of a vehicle but slow fast painting will put too much paint in one area and not enough in another.

Not only will you end up with stripes you will end up with blotches and that can get pretty ugly.

A good way to keep even passes is to count while you paint.

Count as you start the first pass and all of the following ones.. 1..2..3..4..5.. as you make your pass and make sure that you are evenly moving the gun and you always take about the same time for each pass. Also count in your head not out loud or people will think the paint fumes are getting to you.

How to Cure Paint Stripes

Well if you are lucky enough to catch your problem in the booth there are ways to fix the problem before you apply the clear or finish up a single stage job.

Some manufacturers suggest that you mist your paint on the final pass to even out any uneven metallics. This will work for you if you find stripes but you have to be careful about how you do it.

To mist your finish you hold your gun about 1.5 feet from the surface and apply the paint to the whole panel.

Unfortunately misting can change the color of your paint. If you do this incorrectly it will look like you did a spot repair and blended one panel into another so you have to apply it evenly and to the whole panel or vehicle if you are doing an overall job.

You can also allow the paint to cure before applying your clear and add another pass of color coat.

Final Note

Don’t be embarrassed about having runs or imperfect metallics in your first 50 paint jobs these things happen.

Think about it this way if the first time you hammered a nail you were expected to build an entire house do you think it would come out perfect? Yeah probably not.

Get a few project cars where you know you can make a few hundred dollars even if you screw up a bit before you try to tackle that $50,000 restoration you just completed.

If you feel like things are going too fast while you paint then slow down .. but work evenly.

Remember to count while you work…

And watch your overlaps.