Polishing in the Sun ... Good or Bad?

[Prometheus]

So, I was thinking about this today after reading David`s thread about polishing too much. Everybody says that a rotary achieves its results because it heats up the paint. So, would polishing in the sun with a polish that can be used in the sun (the SSR`s are the ones I`m thinking of) make the use of a PC more efficient?



For example, my car is black, and if left in the sun the paint gets really HOT. Anybody with a black car knows this. Would polishing the paint when it is hot like this help make the cutting action of the polishes and pads more efficient? Would it simulate some of the heat produced by a Rotary?



Now, I realize that it won`t create nearly the heat that a rotary would, and would be dispersed over a much larger area than that of a rotary, but would polishing in the sun make the polishes more efficient? I was thinking about it today and really can`t come up with a good answer. I was wondering what everybody thought. With that, have at it.

[togwt]

The fricion heat of a foam pad helps the abrasives in the polish break down, but the `heat` needs to be localized, otherwise its dissapated over too large an area to do any good.



FWIW- the surface temp of a black vehicle in sunlight is approx 200oF the oils / solvents would flash almost immediatly on contact and youd be applying it with no lubrication...not good

JonM

[Anthony O.]

Yeah Jon pretty much sums it up:up



Anthony

[Moodist]

TOGWT and Anthony -



Excuse my ignorance, but are you pretty much saying that even with PB SSRs it is probably a better idea not to polish in the sun? I do not get garage access, so I was considering the SSRs, but I would rather have the Menzerna IP/FP combo.

[salty]

They are talking about surface temp. Sun can cause a surface to heat up very quickly. If it is cool or a little overcast etc. and the surface isn`t hot you can polish outside. Just don`t expect more bite out of your compound.

[togwt]

Salty is correct we are talking about paint surface temperatures-

When polishing clear coat surface temperature should be limited to 100oF (138oC) as urethane starts to soften at 115oF, just like any other plastic material, polishing at this or elevated temperatures will cause scratches to be driven deeper into the surface due to urethane expansion and foam/wool pad friction on the softened paint surface.



Information resource: Heat Vs Urethane Coatings, The Society of Automotive Engineers (SAE) Paper #920738

JonM