Mild or aggressive clay? How does that apply to clay?

[MST3K]

I don't understand why there are some companies that have mild or aggressive levels of clay. The way I understand it, clay is suspended by the lubricant but catches contaminants that are embedded in the paint surface, and which stick out through the lubrication. The surface of the clay is not used to abrade the finish. So why would there be different levels of clay? And if aggressive clay is somehow better at catching contaminants, why wouldn't you use only the aggressive clay to save time?

 

[the other pc]

Since there’s almost zero scientific information available on the dynamics of how clay works here’s my hypothesis:



When everything is operating perfectly the abrasives are held in the clay without protruding, the clay is suspended above the surface by the lubricant film and contaminants above the surface of the finish penetrate the soft clay and contact the abrasives.



In the real world the clay will penetrate the lubricant and contact the finish occasionally. If the abrasives are protruding beyond the soft clay there will be some marring of the finish.



By adjusting the abrasives you can balance speed and effectiveness against the potential for marring.





PC.

 

[Accumulator]

Yeah, just try using a very mild (Sonus green) clay and a more aggressive one side-by-side on a freshly waxed panel. The mild clay won't take off much, if any, LSP but the more aggressive one very well may. You don't have to be so extra-careful when using the mild one.



And some people use, uhm, imperfect claying techniques. It'd be pretty tough to mar your paint with the green Sonus stuff, but people have marred a lot of cars with, for instance, Pinnacle Poly Clay (not bashing, just noting).