Deinonized Water Final Rinse

[SMA335i]

I have access to pharmacetical USP Water which basically goes thru a double reverse osmosis filtration process before finally going thru a membrane deionization process to remove pretty much all dissolved solids and pretty much everything else. I was wondering if I can really leave whatever water is left on the car, after doing a final rinse via the sheeting method, without taking a towel to the paint? I try to do a search on this topic but I could not find the answer. Thanks in advance.

[Setec Astronomy]

You can try searching on CRSpotless, which is a popular deionizer brand here. In theory this works, but I find in practice that there is always water that runs out of a crevice somewhere that is not entirely deionized, and therefore leaves spots. If you have basically unlimited access to this water under pressure, my suggestion would be to use it for the entire process from pre-rinse, to washing, to final rinse, as that gives you the best chance. But there is still likely to be some water somewhere that still has some dirt or some soap in it, and it`s going to leave some sort of spot (depending on the color of your car and what kind of trim etc. that holds water).



Even when I used to use my CRSpotless, I would still blow dry and blot any remaining water with a towel.

[SMA335i]

You can try searching on CRSpotless, which is a popular deionizer brand here. In theory this works, but I find in practice that there is always water that runs out of a crevice somewhere that is not entirely deionized, and therefore leaves spots. If you have basically unlimited access to this water under pressure, my suggestion would be to use it for the entire process from pre-rinse, to washing, to final rinse, as that gives you the best chance. But there is still likely to be some water somewhere that still has some dirt or some soap in it, and it`s going to leave some sort of spot (depending on the color of your car and what kind of trim etc. that holds water).



Even when I used to use my CRSpotless, I would still blow dry and blot any remaining water with a towel.



Thank You for your reply. Unfortunately, I am only able to take the water home with me in 5 gallon bottles. I guess I will still have to blot dry my car. I have a 09 Jet Black BMW 335 coupe and I have read (and experienced first hand) that the paint is very soft. You can pretty much marr/scratch the paint by breathing on it....

[Setec Astronomy]

Hey, you know, pouring your pure water over the car is going to help some, I just don`t think it will be perfect as in walking away and leaving it to air dry. If you`re trying to be "touchless" then use the pure water and blow dry with a leaf blower, air wand, Metro blower, etc.

[medic159]

IMO it`s nearly impossible to get a perfectly spotless car by just allowing it to air dry. No matter how pure the water is there are always airborne particles than can settle on the car while it`s drying and thus cause spots, unless you`re in a computer clean room! The purpose of a good filter is to use it as a rinse which will help keep the car spotless while you blow dry it or wipe it down.

[Downgear]

Thank You for your reply. Unfortunately, I am only able to take the water home with me in 5 gallon bottles. I guess I will still have to blot dry my car. I have a 09 Jet Black BMW 335 coupe and I have read (and experienced first hand) that the paint is very soft. You can pretty much marr/scratch the paint by breathing on it....



I would not be afraid to dry the car as long as you know what you are doing. I have a black s2000 with extremely soft paint as well. I use about 9 high quality waffle weaves that I use once and then wash again before the next time I dry the car with it. If you follow the same process and dry indoors with no wind blowing dirt on the wet paint you will not induce marring. I have washed my car countless times since the last polish a year ago and have close to zero swirls. As long as your drying media is high quality and clean, you will not do damage.

[SMA335i]

Thank You everyone for your tips and suggestions. Knowing from experience (this is my 5th black car) how difficult and nerve wracking it is to maintain a black car, I do not know why I keep on buying the same color. I guess this fits the definition of insanity...

[Stealth]

Thank You for your reply. Unfortunately, I am only able to take the water home with me in 5 gallon bottles. I guess I will still have to blot dry my car. I have a 09 Jet Black BMW 335 coupe and I have read (and experienced first hand) that the paint is very soft. You can pretty much marr/scratch the paint by breathing on it....



Ah the dreaded jet black paint! Just make sure you sheet most of the water off the paint and you will only have a minimum amount of water to blot off when drying. With the combination of deionized water, proper sheeting and blotting (with a good quality drying towel), the drying process should be the least of your worries - it`s really the washing step you should be extra careful with - good luck! :xyxthumbs