ok. i feel really rediculous for having to resort to asking this here, but its my last resort.

i have started my project. i finally got my penetrol and everything i need. i have snaded and prepped my replacement fender. i have started sanding the rest of my car.

my question is, how much do i have to sand this thing? the car is a light blue. when i sand a lot i hit three different colors. one, the blue gets darker. i assume this is when im past the clear coat. the next, i hit white. i assume primer. third, i hit metal. ive only hit metal where ive needed to to remove rust.

my paint is good, a little sun faded in parts, but nothing bad. do i have to sand all the way through the clear on the whole car? or do i just need to spend some time on a spot and make sure its rough. i just dont want to waste a lot of time going through the clear on the whole car if i dont have to.

any help is greatly appreciated.

thanks.


just wanted to add. im wet sanding with 400 and a block. im also using a 320 sponge. it doesnt feel like i can get as much done with the sponge, its too soft.