hydrophobic beading

[john.r2k]

I use the AutoGlym Polar Seal as the final stage of car wash which creates a hydrophobic layer and water beads very nicely on it. One thing I noticed with a hydrophobic layer is that if for example it rains overnight (specially in winter) then the next day most other cars on my road all dry up by the morning but the water beads remain on my car almost all day on to the next day and on and on. On cold days it's almost like it never disappears lol. Is this normal? Ofcourse if I drive then these beads of water fly off.

[Chris32345]

A thin layer of water will heat up and evaporate quicker in the sun

[Chubbyross]

Chris32345 said:

A thin layer of water will heat up and evaporate quicker in the sun

This. Beading is actually a bit of a pain, especially for those of us who live in a dusty, dirty city. By the time the beads have evaporated you can end up with dusty bead-shaped marks on your paintwork.

[tejr]

I've never understood the fascination with beading tbh.. I used to spend a weekend washing and waxing the car, only for it to gather dust while parked up and the first time it'd rain and dry off my car would be left with leopard spot dust marks and would look filthy compared to all the other cars in the street that hasn't been washing in months.

Different story now I have a garage though.

[Belle427]

I notice it more on my red car than I did before as it looks terrible,
I’m not sure if some products sheet the water rather than bead?
I’ve recently invested in a battery garden blower so I can blast it off when I feel bothered!

[john.r2k]

To be honest I don't apply it because of the beading craze but mainly because it really does prevent dirt from sticking so i do a big wash and then just do a snow foam rinse washes in between and re-seal it. When it rains heavy enough then all the dirt just washes off. So that's the biggest advantage for me. And if it's able to do that then surely it definitely must be a layer on top of the paint protecting it. Not to mention protection from UV in the summer season.

Regarding the beading not drying out in cold weathers compared to a unsealed car. Having spoken to a number of other professionals and consulting manufacturers, it seems that the reason the water beads just stay on the car for most of the day in winter is because the temperature isn't hot enough to evaporate the beads of water in time and then it becomes night again then just repeated. Whereas an unsealed car a lot of the water is evaporating on to the surface of the car itself. Whereas a sealed surface the water is essentially floating and needs to evaporate into the air.

[swisstoni]

There used to be a product marketed that purposely did the opposite of beading. They called it sheeting. Water would simply leave the paint surface ASAP rather than gathering in beads.

One part of the infomercial claimed that water beads acted like tiny lenses in strong sunlight and actually did the paint no good.
It could just have been advertising BS of course but I’ve been a bit unsure about beading and the sun ever since.

[droopsnoot]

swisstoni said:

One part of the infomercial claimed that water beads acted like tiny lenses in strong sunlight and actually did the paint no good.
It could just have been advertising BS of course but I’ve been a bit unsure about beading and the sun ever since.

That's certainly a thing on cellulose paints - one of my classics is cellulose, and a very dark colour, and it can cause some issues. A mate of mine with another classic painted in cellulose will get out with the chamois if we're at a show, the rain stops and the sun comes out. The effects can be removed with compound, but it's easier to leather it off if you can.