There are many cumbersome procedures for auto refinishing, and it is relatively easy to cause defects with the paint surface after painting. Let's talk about sandpaper marks expansion today. As the name implies, it means that there are obvious sanding marks on the surface of the automotive paint. so why happens?
1. After the bottom layer is sanded with coarse sandpaper, the sandpaper marks are not filled with putty or primer.
2. The mixing ratio of the thinner is improper, and the thinner that in the newly sprayed topcoat will penetrate into the old paint layer, causing the sandpaper marks to expand.
3. The professional skills of the paint technician are poor. besides, this situation will also occur when there is still a lot of sand and dust on the auto paint surface, but spray paint without cleaning.
If the sandpaper marks have expanded, it is recommended to sand the defective district by dry sanding or wet sanding until smooth, then scrape putty, and spray the car primer and topcoat.
