This is a guide showing the principle and methodology behind spraying. It is quite straight forward as long as you follow the steps shown. It can also be quite fulfilling when you see the end result. You can buy most of the necessary equipment from hardware, automotive stores or Halfords.
The first step is to flat back the surface with wet and dry paper. Depending on the condition of the surface you will be spraying you may wish to start with a more aggressive paper then move on to a finer one to gain a smoother surface finish.
In the example there are a few scratches and imperfections that require filling. An automotive filler is used (such as Davids/ UPOL), which is mixed with a small amount of hardener. It is important to mix it well until a good consistency is achieved, or some parts will harden and others will not. The filler is then applied to the imperfections, using as little as possible, so that there is less to remove when it has hardened.
Once the filler has properly set, it can be sanded back with a medium grade paper. As the filler is sanded back the grade of paper used should be finer, to achieve a smoother finish. Mask up everything that you don’t want paint or overspray to land on. You’ll probably be surprised to see how far overspray can travel.
Now clean the surface and check that it is very smooth without imperfections. Ensure that there are no dust or hair particles on the surface, and that it is fully dried from any water or residue. The surface can now be painted with a primer. You can use an aerosol primer, or if you have spray equipment use that as you’ll get a more consistent finish. If you are using an aerosol, ensure that it is shaken very well before use. They also work better if they are used in the warm. Spray from left to right, about 300mm away from the surface. Some people like to cross left, right, up, down, when spraying. It’s up to you, do what you find easiest to achieve the best result.
Once the primer painted layer has dried smooth it back with a fine grade of paper. Depending on the thickness of your paint or imperfections that need correcting, you may require additional layers of primer. Once it is all smooth and free from dirt you can spray the first coat of colour using the same method.
Continue to add more coats of paint until you have a consistent finish. At this stage you may be happy with the finish. If you are happy it is difficult to bring the sandpaper to it, but you must. Sand it back gently with a very fine grade paper, so that any dust in the paint or imperfection is taken out.
Clean and dry the surface, and then apply a layer of lacquer in the same way as the colour paint. Be careful not to create any runs when spraying lacquer, as it is difficult to see how much you are applying. It is good to add a few coats of laquer, as it will make it very shiny. When the lacquer has properly set it can then be sanded with a very fine grade of paper in the same way as the colour paint.
This can then be polished out with automotive grade paint polish to achieve a very shiny finish. Additional parts can be added. You may now sit back and stroke the smooth paint finish.
Let me know what you think of the guide
Paper Grades:
Extremely rough = ~80 grit
This is used for heavy shaping, and has large grit which will leave deep score marks.
Medium = ~400 grit
Good for shaping filler without leaving any horrific marks.
Fine = ~800 grit
Ideal for ridding slight imperfections in surface or paint work.
Very Fine = ~1200 grit
This is getting on to be a polish, and is used to finish off the surface. You can go higher, but usually no more than 1500 in paint work.
The first step is to flat back the surface with wet and dry paper. Depending on the condition of the surface you will be spraying you may wish to start with a more aggressive paper then move on to a finer one to gain a smoother surface finish.
In the example there are a few scratches and imperfections that require filling. An automotive filler is used (such as Davids/ UPOL), which is mixed with a small amount of hardener. It is important to mix it well until a good consistency is achieved, or some parts will harden and others will not. The filler is then applied to the imperfections, using as little as possible, so that there is less to remove when it has hardened.
Once the filler has properly set, it can be sanded back with a medium grade paper. As the filler is sanded back the grade of paper used should be finer, to achieve a smoother finish. Mask up everything that you don’t want paint or overspray to land on. You’ll probably be surprised to see how far overspray can travel.
Now clean the surface and check that it is very smooth without imperfections. Ensure that there are no dust or hair particles on the surface, and that it is fully dried from any water or residue. The surface can now be painted with a primer. You can use an aerosol primer, or if you have spray equipment use that as you’ll get a more consistent finish. If you are using an aerosol, ensure that it is shaken very well before use. They also work better if they are used in the warm. Spray from left to right, about 300mm away from the surface. Some people like to cross left, right, up, down, when spraying. It’s up to you, do what you find easiest to achieve the best result.
Once the primer painted layer has dried smooth it back with a fine grade of paper. Depending on the thickness of your paint or imperfections that need correcting, you may require additional layers of primer. Once it is all smooth and free from dirt you can spray the first coat of colour using the same method.
Continue to add more coats of paint until you have a consistent finish. At this stage you may be happy with the finish. If you are happy it is difficult to bring the sandpaper to it, but you must. Sand it back gently with a very fine grade paper, so that any dust in the paint or imperfection is taken out.
Clean and dry the surface, and then apply a layer of lacquer in the same way as the colour paint. Be careful not to create any runs when spraying lacquer, as it is difficult to see how much you are applying. It is good to add a few coats of laquer, as it will make it very shiny. When the lacquer has properly set it can then be sanded with a very fine grade of paper in the same way as the colour paint.
This can then be polished out with automotive grade paint polish to achieve a very shiny finish. Additional parts can be added. You may now sit back and stroke the smooth paint finish.
Let me know what you think of the guide
Paper Grades:
Extremely rough = ~80 grit
This is used for heavy shaping, and has large grit which will leave deep score marks.
Medium = ~400 grit
Good for shaping filler without leaving any horrific marks.
Fine = ~800 grit
Ideal for ridding slight imperfections in surface or paint work.
Very Fine = ~1200 grit
This is getting on to be a polish, and is used to finish off the surface. You can go higher, but usually no more than 1500 in paint work.
I feel it is more the choice of rattle can paint that I have been using.
I figure that I should be fine adding within reason whatever paint I like to the primed surface in thin layers, so i'll start that later tonight.
