Depends on how you plan on sanding it and the size of the car.
If you’re going to sand it with a DA sander, with 320 grit paper, probably less than two hours for an average sized 4 door sedan.
If you’re going to wet sand it, with 400 grit wet-or-dry paper, probably between 3-4 hours for an average sized 4 door sedan.
Of course these times are for an experienced professional working hard to make a paycheck. A DIY’er sanding a car for the first time will probably take much longer.
you’re able to sand aspects the place upkeep have been made with gradually larger grit sandpaper until the perimeters have been “feathered” or made mushy as you rub the palm of your provide up it. Layers of primer between sanding help the technique.
it depends on the size of the car but i sat there for a day and only had half of the car done.
use 32 grit and you’ll be to bare metal in seconds