BASECOAT/CLEARCOAT

          In the mid 1980’s, cars and trucks were being made with thinner and thinner steel bodies to reduce the curb weight of the vehicles.  Everything that could be done to get better gas mileage was being done.

          By folding and creasing metals, the same strength could be had without having to carry around the extra weight.

          The technology of building cars and trucks that fold up around you if you have an accident also changed the way vehicles were built.

          It had become time to create a paint system that was flexible enough to expand and contract with the new thinner metals and plastics as the temperature changed and be flexible enough to stay with the car door when you lean on it and push it in.

          The entire automotive industry adopted acrylic urethanes.  These sprayable plastics have all of the flexible properties to stay on the car.  They don’t fade.  They can be driven into whatever the weather presents them at 83 miles per hour and come out as good as before.

          The technology of applying paint changed at the same time.  People wanted cars and trucks with pearls and fancy metallics.  In the “good old days” the car painter knew how to adjust the color of the metallics by how much air pressure, how much thinner, how fast the thinner evaporated, how far away from the car…all kinds of things to do to change the color.

          Except most of the time, the repainted fender still didn’t look quite like the original finish.  There were too many variables.

          Because the OEM’s, original equipment manufacturers, had begun putting the color on first and then putting clear over the top, it had become time for the refinish paint companies to make a product that would match the OEM finishes.

          Welcome to the wonderful world of chemistry.

          When you pull the trigger on your spray gun, fluid suddenly comes out of the front of the gun as the needle is pulled back.  The fluid suddenly has a lot of space to accelerate into.  0 to 60 in less than a second flat.  Is that street legal?

          This rapid change in volume makes the fluid become very cold very quickly.

          Understanding this sudden coldness, the chemical engineers at the automotive paint companies added a product to the basecoat colors that has lots of names:  stabilizer, basecoat fixe, reactive reducer, etc.  Everybody’s product is a trade secret and they’re all the same.

          By using a “bulky” hydrocarbon, sometimes called alkane or paraffin or wax, in the paint coating, when the trigger is pulled, a temporary electrical charge makes static lines run across the paint surface.

          While the paint is wet, the tiny electrical charge forces the metallics or pearl micas to arrange themselves in rows and columns just like a checker board.  All you have to do is point the gun at the car and the color will become the correct color.

          It’s amazing isn’t it?

          And the stabilized or fixed paints can be used for a very long time as long as no hardener has been added to them.  They cover like a blanket.  Usually three coats only a few minutes apart and the whole car is covered.

          After about twenty minutes or so of dry time, the color is ready for the shiny top coat.  You’ll want the clear on top too; because when the color dries it is as flat as asphalt.  Dirt flat!  We talkin’ flat here!

          The first coat of urethane clear is applied over the top of the color.  As you come back around the car, it looks as if you didn’t spray the clear on it.  It’s almost flat again!

          That first coat sinks down into the color and makes it hard and flexible and what will finally make it dry.  It just sucks right into the colored pigment and marries itself into the whole coating.

          This means, of course, that you don’t want to hose the color on just because you have it in the gun.  As soon as the color has covered, quit putting it on the car.  Geez!  You don’t keep drilling for oil after you have it coming out of the ground!  The clear is only going to go in so far and then it quits, so don’t expect it to harden 15 layers of paint!

          It usually takes three coats of clear to make shiny happen.  You’ve seen that bumper sticker?  SHINY HAPPENS.  But it doesn’t happen in the first coat!

          Anyway, that’s all there is to it.  It’s so easy.

          If you get a run in the clear and don’t notice it enough to take it out while you’re painting, you can color sand and buff the finish later without screwing up the metallic or pearl or color.

          A few pointers:

          1)  Urethane is moisture cure.  Once the hardener or catalyst or activator (all the same thing) is added to the clear, the CLOCK IS TICKING.

          Whatever you don’t use today will NOT be okay to use tomorrow!

          2)  Your painting area needs to be bone dry.  Any moisture evaporating up from the floor will pass through the space at the end of the spray gun…remember the spray gun?...when you pulled the trigger, the paint/clear got real cold!  The evaporating moisture from the floor turns some of the hardener into plastic beads on its way to the car.  Geez! I got a lot of dirt in my finish.  (Nope!  You put a lot of “dirt” in your finish.)  This doesn’t hurt the paint and the paint store dudes will love you because you’ll spend extra bucks buying sandpaper and compound to make SHINY HAPPEN.