The Painting of automobiles is an art as well it is same as painting your house but with a lot of extra working
The main thing in doing a repaint of a car is "sanding" u have to do sanding before everything you do when painting a car i.e
1: Before starting to paint u have to sand it too get the previous paints gloss out completely so the surface can become prepaered for the new paint (if repainting on the previous paint)
2: After the gloss is done u apply the premier and u have to sand it again to get a smooth enough surface that the paint will stick to the premier and not rough enough as well so that the paint doesn't produce deflects due to low adhesive surface . usually its done with a p800 sanding paper with or without a sander
3: After the premier its the surfacer sanding job if it is required but now a days the premier comes with the surfacer so it requires only the premier sanding
4: Then come the last sanding of the paint which is done using the p1200 or p2000 sand paper to smooth the paint surface that gives it the smooth and shiny gloss look
5: If u want even more detail and smoothness then u sand it even more with the highest no of sand papers like p4000 ( this is the last of the no sand papers on the car ) but it is not necessary that u do this
Hope this was helpful
And if i am wrong plz feel free to correct me !
The main thing in doing a repaint of a car is "sanding" u have to do sanding before everything you do when painting a car i.e
1: Before starting to paint u have to sand it too get the previous paints gloss out completely so the surface can become prepaered for the new paint (if repainting on the previous paint)
2: After the gloss is done u apply the premier and u have to sand it again to get a smooth enough surface that the paint will stick to the premier and not rough enough as well so that the paint doesn't produce deflects due to low adhesive surface . usually its done with a p800 sanding paper with or without a sander
3: After the premier its the surfacer sanding job if it is required but now a days the premier comes with the surfacer so it requires only the premier sanding
4: Then come the last sanding of the paint which is done using the p1200 or p2000 sand paper to smooth the paint surface that gives it the smooth and shiny gloss look
5: If u want even more detail and smoothness then u sand it even more with the highest no of sand papers like p4000 ( this is the last of the no sand papers on the car ) but it is not necessary that u do this
Hope this was helpful
And if i am wrong plz feel free to correct me !