| dont want you to know. ;-) ADMIN: Please leave this in general until tomorrow and then move it to tech as I believe the members will want this in the FAQ section. I would just like it to get a little exposure for a day. -Thanks! I have compiled this information because of the unbelieveable results you can get from a rather simple process. My car was produced in september of 1990 and is a 1991 model. The factory paint is awesome as hell in comparison to other cars mainly because they apparently put down a good amount of clearcoat, but the factory paint still leaves a lot to be desired - specifically the elimination of 'orange peel'. This is a byproduct of painting a surface that is vertical in which gravity itself 'pulls' the clearcoat as it is curing and it causes the surface to become irregular and composed of small 'high' and 'low' spots. This can be seen by looking closely at the reflection off the surface of the paint. The reflection will appear 'muttled' or 'pitty'. This is due to these inconsistencies of the surface of the clearcoat due to the 'creeping' of the paint as it cures. Paint basics:
Our cars are painted with a two-step paint job. The structure of the car is assembled and the metal that makes up the unibody and panels is already treated before it is even assembled. It is ready for painting even before it is all welded together to make the car we all enjoy and love. The paint is composed of two parts that are sprayed on seperately. The 'color' of the paint is a laquer 'base coat' which composes the actual color of the car itself. Although this produces the color of the car, it does not have a nice 'glass' finish to it to bring out the color. Typically the base coat is 3 layers deep. In fact, it is actually a very dull finish. To top off the basecoat and give it the shine we all look for, a polyurethane 'clear' coat is applied. Typically this is 3-5 layers thick, depending on the manufacturer. Apparently Nissan thought ahead (go figure) and they 'overengineered' the paint of the car. What this means is that they apparently anticipated that people would want the best possible finish available without having to repaint the whole car. What all this comes down to is the thickness of the clear coat itself. A clearcoat that is too thin will not allow for wetsanding and buffing as you will simply 'sand' through the material and essentially ruin the finish in the attempt to 'smooth' out the clear. Fortunately for us, there is plenty of clearcoat on the car which allows for wetsanding, buffing, and polishing. Here's the technique: There are, of course, the weapons of war. 
What you see here is a highspeed buffer/polisher which has a user adjutable operating RPM from about 800RPM to 3000RPM. This puppy is about $150, but if you are a true enthusiast, you will buy one. This is the most potent weapon in your artillery. It already has a pad on it which is made from wool. This is an aggressive pad which is used to bring the 'shine' back. The yellow pad is a softer pad which is used as a 'finish' polisher. The bottle with the green stuff in it is a special 'coctail' I drummed up which is essentially a swirl remover and a wax, mixed together. Nevermind that though, the two bottles of Meguiars are your chemical warfare components. You see that there is the Meguiars "polish" and the "carnuba wax". These are both readily available at Auto-Zone, inexpensively. The other two components, the sandpaper and the greyish, round pad, are used as the sanding utensils. The sandpaper is obviously 2000 grit paper. This means there are 2000 particles of 'sanding' material per inch, or, the grain size is 0.0005". This is five tenthousandths of an inch. Very small indeed. The round pad is actually 3000 grit pad, which takes the ante up to 0.0003", or three tenthousandths of an inch - a much finer grit. These two variances in 'grit' will allow us to smooth out the finish of the clearcoat to eliminate the 'orange peel' effect and make the finish as smooth as glass. The 2000 grit paper is more aggressive which allows for us to smooth it out relatively quickly rather than rubbing our fingers off. The 3000 grit pad allows us to smooth out the finish a little more to ease the process of bringing back the shine with as little swirl as possible. Step 1: Wetsand with 2000 grit paper.
 As you can see, water is being used while sanding. This is to allow the 'sanded' material a medium to be carried away with. Without water, the sanded clearcoat would build up on the sandpaper and the paper would clog - no longer sanding the material anymore. The water also provides a 'slippery' medium that keeps the paper from grabbing the material and marring up the surface. Water is key here. In this picture you can also see the orange-peel off to the left of where I am sanding. Look at the line between the dark and light area directly left of my last finger knuckle and you can see how this line appears 'wiggly'. This is because of the inconsistent surface, or 'orange peel'. This is what the sanding is eliminating. 
This is an excellent picture that shows you what orange peel is. You can see that after a little sanding, the areas of the clearcoat that are 'high' are now dull, but the areas that are 'low' have not been touched by the sandpaper and still remain glossy. You can also see what is called 'fisheye', or the little spots that look like a fish eye. ;-) The object here is to eliminate all of the orange peel as well as any 'fisheyes' that exist. 
In this picture you can see that I have now further sanded the surface to eliminate both the orangepeel as well as the fisheyes. Continue to sand and dry off the work area just until you make it smooth like this. This is where you want to get to with the 2000 grit paper and then you are ready to move to the next step. 
Again, sanding. But now you are using the 3000 grit pad. Since you cannot see the markings of this pad by drying it off and seeing where you have sanded, the object is to sand the entire area evenly. Dont spend more time in one place than another. This step goes quickly and you only need to make about 3 quick passes over one spot to achieve the result you need. At this point you are ready to buff the material to get the shine back. Use the wool pad at 1800RPM and the meguiars polish for this step. Even after just momentarily applying the polishing wheel to the paint you will notice the shine 'jump' right back into the clearcoat. As you continue to buff an area (move the wheel around as it turns, kindof like how you would hand-wax the paint) you will notice that the hazing from the sanding will continually disappear. You should continue to buff until the haze is gone and if necessary, apply more of the polish to the paint. 
You can see here the difference between the polished surface and the sanded surface. Quite drastic. Continue buffing/polishing the surface until all of the sanding haze is gone. Once you have gotten to this point you are ready to wax. 
When you buff the wax away, here's what you are left with.
I have previously sanded/buffed/polished my Z using this same process and here are a number of additional shots. Once you have done the whole car, it literally feels as smooth and soft as slippery glass - it also looks like glass as well.
This is the same process that high-end paint shops use to produce the results everyone pays thousands of dollars for. The painting of a car is literally like putting the icing on the cake. A huge part of making a paint job 'show quality' comes down to the preparation before the paint is applied, followed by a good amount of finishing the surface as seen above.
Some members have 'clay-bar'd' their cars before and I have as well. It produces a very smooth finish on the car but it does not eliminate the orange-peel as the above process does. If you have any questions/concerns about this, please email me or openly post about this as I am open for advice/consultation on this process. -Enjoy!
[ ashleypowers.com ]
[ agpowers@bellsouth.net ] [ Zemulator Information Sheet ] Enthusiasts soon understand each other. --W. Irving.
Are you an enthusiast?
|
Wetsanding, Buffing, Polishing: 101 - The things the 'pros' - 
21:32:05 05/29/03
