Car painting 101...

I have been asked by some who have seen the car, about the seemingly disorganized process of undergoing a repaint.  The other day, a couple of them even commented that with the car looking like it does now, its about time that spraying begin.  They did not realize that the paint has already been applied.

For the benefit of those who have no idea of what takes place, let me try to present the process in as understandable a way as possible.  In layman's terms so to speak.  By the way, I also consider myself a layman in this field as my experience is limited to what I have seen being done to other cars in the past.  In watching the different steps undergone by Sergio, I am filling in a large number of gaps in my own knowledge pool. 

The way I see it, most of the confusion arises from the notion of most people that painting a car is the same as painting a wall.  Choose a color, mix the paint, brush or spray it on, wait for it to dry, and that's it.  WYSIWYG: what you see is what you get.  Unfortunately, car painting is not as straightforward.  Because the demands are more stringent, there are a lot more variables which come into play.  The two most obvious requirements are that the finish be smooth and that it have the ability to maintain its gloss.  I have no desire to delve into the technicalities but through the following pictures, I hope it will be easy to see how this is achieved.  A number of previous posts have shown the preparation and spraying stages so I will not go into those either and instead just concentrate on how to get to the end result.

When I saw the car earlier today, the hood and both front fenders were just being attached and this presented a great opportunity to see the three basic stages of paint treatment.  Notice from the picture below that the hood, fender, and doors all look different although they have actually been sprayed with the same paint.

The hood represents the first stage wherein the paint has been sprayed on and dried.  While it may seem shiny enough, a closer look reveals as the next picture shows, that the surface is very uneven; a result of airborne contaminants and the inevitable excess paint runoff.  There will even be a few stuck insects somewhere. 

The surprise here is that (and contrary to what normal intuition would dictate), to remove these surface imperfections, the paint has to be sandpapered down which also results in removing the gloss.  The fender shows how it ends up after being sanded and it would seem like everything is back to where we started from: faded and dull paint. 

To restore the shine, the sanded surface is then buffed using a very fine grit compound and after a couple of passes becomes more indicative of the paint's final finish as seen on the doors below.

The secret is in the sanding process.  It is done by starting from a rougher grit and eventually progressing to a very fine one.  The rough grit removes what should not be there and going on to smaller and finer grits polishes the surface.  Of course, this is all easier said than done.  I maintain that painting is more art than science and even if I am now more aware of the process, it does not mean I will dare venture any small retouchings myself should the need come up.

Best leave it to the professionals...