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mobiledynamics
09-30-2019, 06:14 PM
I broke the Cardinal rule....by washing in the sun.

Crazy resources of time, so I washed the car in the only hr I had which was middle of the day, with clouds going in and out. I noticed when using the blower on the car, water behaved differently with the sun/hotter panel


Instead of the water being moved by the air of the blower, I observed that was a percentage of water that broke up into micro-beads and all I was doing with the blower was breaking up the water into mico-sized balls and just blowing balls of water - round and round on the panel. I`ve never experienced this so I`m attributing this to the overhead sun and warm-sun hot panel. For those that are into cooking.....I observed the Leidenfrost effect ;-)

Hope all is well with ya`ll forum members. Been awhile since I`ve been on

Lonnie
10-03-2019, 01:30 PM
You are not breaking a "cardinal rule" of washing in the sun IF you are using the "right" soap and distilled or de-ionized water.

The closest soap within this forum that kind of "minimizes" this mineral spotting problem was what now deceased Forum All-Star Ronkh wrote in his thread about McKee`s 37 SIO2 Soap. It is worth reading and considering:
https://www.autopia.org/forums/detai...highlight=wash (https://www.autopia.org/forums/detailing-product-reviews/188294-ultimate-torture-test.html?highlight=wash)
The photo links no longer show due to Bucketlist`s licensing requirements. My questions are in Post #8 and Ron`s response in #9.


The Leidenfrost effect?? Wikipedia says: https://en.wikipedia.org/wiki/Leidenfrost_effect (a LOT more science and math than I want to delve in to!)

What else has effect on this water beading phenomenon is the LSP that the water is sitting on which will affect water surface tension because of the co-efficient of friction AND the color of the paint which will affect the ambient heat temperature and thermal transfer AND the angle of the panel, which needs to takes gravity into account, assuming it is not exactly flat. Nor do we know how much wind velocity and CFM (cubic feet per minute ,which is air volume) your blower was blowing with. An additional mathematical formula to those listed in Wikipedia will need to be derived from your empirical test data and observations to determine how small those water balls really get! (Captain Obvious, a physicist you are NOT. More like a.... ,well, we cannot post that here without being banned for life from this forum.)