I do think wet sanding or even using a circular polisher are OTT for a car in good condition. I am no expert but am happy with the results I have on my red MINI.
If I were you, I would wash with Fairy Liquid to strip the old wax. Rinse and clay bar. Use a paint cleaner/sealant (e.g. Klasse AIO) or if you are able to wax often enough, just wax it.
I like P21S, but it does not lasy very long so now use Collinit 476S. Really easy to use, finish is great and durability seems very good.
Only problem with Zymol it has to be applied in a warm environment with some heat in the bodywork. Can only get the right conditions inside this time of year.
I don't think anyone on this thread is actually suggesting wet sanding, rotary or DA polishing good paintwork....well I certainly don't recommend that.
But if you have swirls...and they annoy you...those guys that have PC'd their cars seem to be happier afterwards.
Ian has been to Andy's car and I'm sure will have given Andy some good advice.
I've seen cars pre delivery that need paintwork corrected. I know that Mr Davies asked for both his 56's to be delivered without the wotsit cleaning work done to it...so that he could ensure that a dealers dirty sponge didn't touch the paintwork.
If you have ever used a PC....you will know how slow it is to correct paintwork defects...this in essence makes it ideal for the job. You would have to have big feet and red nose to damage the paint on your car with a PC.
A rotary polisher can damage paint in seconds.
As Ian suggests....heat is required to break down the grit in the polish. This diminishing grit polish is another reason why you get such a good job. Starts "abrasive"...and breaks down to a fine polish.
Anyway...I checked my bonnet again today...I've picked up more stone chips on the bonnet...and on my aero front bumper:(
But at least I will have fun sorting them in the spring:)
There's a couple of bits on my car that I want to work on....so the spring will be time enough to look at them.
Over the winter....I'm just happy to wash.
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