Tips & Tricks to washing in the sun.

[Todd@RUPES]

For best results, washing in the shade, at dusk, or at dawn is recommended. The reason is simple. Washing in direct sunlight, even on a cool day, speeds up the evaporation of water. This leads to several issues when washing:

• Water spots
• Soap Film
• Spotty Appearance

Water Spots usually form after the surface is rinsed clean and tiny droplets of water (water beads) forum. Because water beads have a small surface area they begin to evaporate quickly. Any solid material in the water is left behind. In direct sun light the curvature of the water bead can create a lens effect that which heats the surface of the paint quickly, increasing the reaction. Water spots can form very quickly in direct sunlight, particularly on a dark car.

Soap Film is another possibility. As you wash the car the water in the soap solution begins to evaporate, which changes the dilution of product on the surface. If too much soap is present, the chemicals in the soap can form a film on the paint that is difficult to remove.

Spotty Appearance: After washing and rinsing the vehicle, you begin to towel dry it. Any moisture that is left behind is often spread very thin. This can almost instantly evaporate leaving behind a streaky/spotty appearance similar to water spots.


A different plan of attack:



When washing a hot surface we must systematically reduce the chance of soap film residue and water spotting.

Do the wheels and tires first.

Choose a car soap that rinses clean and resists water spots from forming. The very best I have found, thus far, is Ultima Paint Guard Wash. This soap is also easy to rinse, even in extreme dilutions, so you can work several panels at a time with out the fear of soap film. Remember that water spots form after the surface is rinsed and water beading occurs.

Wash the vertical surfaces first if the sun is overhead. Generally it is recommended to wash the top (horizontal) surfaces first and work downwards. However, in the sun, the top surfaces are more prone to water spotting. By washing the sides first and rinsing them, then the top you are decreasing the time that the areas most prone to spotting are exposed to water and soap. When you wash and rinse the top, water will run off on the sides. Keeping the water moving will reduce the chances of water spotting.

Rinse frequently! Once you rinse a section of the vehicle, you will need to rinse it frequently. The running water will help carry heat away from the surface as well as prevent any water spotting.

If you have any shade, use it! Even if it is under a tree or the shade of a building. Wash and rinse any areas in the shade first, and save areas where the sun is most direct for last, since you will have far less time to dry these after rinsing.

For the final rinse, start with the areas most exposed to the sun first, then work quickly around the vehicle, working back to the area where you started.

Flood the paint twice! Removing the nozzle from your hose and allowing the water to flood over the paint is a great way to remove a majority of water droplets from your paint. If you take your time and do a thorough job you can usually remove 80-90% of the water before drying your car! However in the sun, time is a valuable commodity. First quickly flood the paint to remove as many standing water beads as possible. What we are trying to do is stop these little beads from creating water spots as well as keep running water over the surface. After you quickly sheet away the tiny spots you can come back and do a second flooding application to remove the majority of the water.

Towel dry before blow drying. Many of us the filtered blast of a Metro MasterBlaster or leaf blower to remove standing water. The problem is that blasting the water creates little droplets (which are prone to water spots) and it can take time (which you don`t have) to knock all the water off. Instead use a soft, large waffle weave drying towel such as an Ultimate Guzzler Waffle Weave Drying Towel to remove the water. Start drying any areas that are exposed to the sun first, then work around the sides. You can add a quick spray of a quick detail spray, such as BLACKFIRE Midnight Sun Instant Detailer to the panel before you wipe to help knock down any remaining water beading and clean the paint as you towel it.

After toweling the car, you can come back with your MasterBlaster or leaf blower to knock any water out of the cracks and crevices, and immediately towel the water spray off.

As a last step you can towel the paint with a high quality quick detailer or waterless wash to remove any residual soap film or faint water spots that might have started to form. I use BLACKFIRE Wet Diamond Waterless Wash for this step with a Gold Plush Microfiber Towel. One light mist per panel is all that is needed.


As a professional detailer I have come to situations where washing out of the sun was simply not possible. I have washed many cars in the direct Florida sun and these are the tips, tricks, and techniques I have used. Ultimately, if I can, I prefer to wash a cool surface in the shade because it is just easier. But with a little planning and a little tweaking it is possible. I hope this article helps.

[Bunky]

Interesting write up.

It is a little different than what is normally discussed as proper such as towel drying vs the Master Blaster.

I only wash in the early morning or late evening and do not rinse that much. I do see the droplets that the Master Blaster generates but learn not to try to get every drip off water off the paint using the MB. You herd most off and then go around and find the spots since you can dry them on the paint especially those with weak LSP.

[ca.detailchick]

As a mobile detailer I can say I wash vehicles in the sun all the time .Even if you have a tent you come across situations where there is not enough room to set it up,so you must be able to work in full sun conditions.

Good tips!

If you are using clay in the wash process I find doing a couple panels at a time to work well for me.

[TroyScherer]

Some good info here Todd.... There are times I will wash out in the afternoon sun just to be able to wash a car because it is so nice out.

[Old Pirate]

Great write up and tips there Todd, I recommend for anyone to get a CR Spotless water system or if you have a large tank then try finding someone in your area in getting De-ionized Water which won`t spot on the paint when washing.

[Todd@RUPES]

Great write up and tips there Todd, I recommend for anyone to get a CR Spotless water system or if you have a large tank then try finding someone in your area in getting De-ionized Water which won`t spot on the paint when washing.

Yes, the CR Spotless makes a huge improvement in the being able to wash in the sun. I own two of them!