I have what looks to be water spots on my car I'm not sure if that's what they are but I can't seem to get rid of them Iv washed the car 4 times this weekend and just Clayed the hood and they will not go away help!!!'
^ it's in the center of this picture
Not all water spots are the same. Some can be removed chemically and other may require polishing or even sanding. Below is a great article that covers the different types of water spots.
It will vary be region but my understanding in rainwater has very low TDS in it, less then 10ppm from what I recall reading somewhere. I've never had any spotting issues with rainwater in my area. You may see spots of the surface from the dust that was on the paint, but they should easily wash away. However, in cities with high pollution you may have issues with acid rain, but that's something I've never had to deal with here. I have had cars back in the day that were shipped to local auctions from other states, which were hammered with acid rain! They were not fun to work on either....
Thx, Rasky............ Great thread.......... I use to go to a lot of car shows with a friend that could pull the 1st places quite a bit...... I learned a bunch from him, but your info is more interesting and detailed with why & wa'foos.