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togwt
07-30-2011, 08:48 AM
Water Spots



[A water spot is an area of dried mineral deposits left on a surface after being allowed to air dry. Water quality, specifically the amount and type of minerals in the local water supply as measured by the total suspended solids or TSS test and other mineral levels such as sodium level, has a big effect on how severe water spots can be] [1]



If the surface can be rectified by chemical means then this is the answer; not abrasive polishing. Using the correct chemical cleaners will dissolve the contaminants rather than abrading the surface.



If water spots are not washed away using normal car wash they might be etched into the wax or paint surface. The next step would be to use a paint cleansing lotion or the cleaner wax indeed. Don’t use a pure carnauba product over the water spots as it has no ability to remove them and will seal them in. You can move to machine polishing as needed, but most the time newer water spots are removed with a chemical paint cleaner type product or distilled white vinegar



With all cleaning products (especially solvents) always test a small inconspicuous area first to ensure it won`t discolour, stain or etch the surface, and ensure that the pH of the product is suitable for the material After the paint surface has been subjected to a chemical cleaning its protective layer (s) have been removed and the paint surface left without protection, so it is very important that a polymer and / or Carnauba wax protection be applied immediately



Water doesn’t leave marks or etch glass; it’s the minerals that it contains calcium (Ca) and magnesium (Mg) and reactivity (heat acting as a catalyst) the spots are actually traces of minerals left on the surface. Alternatively they can be caused by industrial pollution (i.e. acid rain, bird excrement or industrial fallout)



Generally surface water-spots have no raised edges and are very shallow and so cannot be felt, they are very similar to micro-fine surface marring. They cannot be removed from the surface by washing but they can usually be removed with a slightly abrasive chemical paint cleaner



There are two categories of water mark (the so-called water spots)



1. Stage I (Surface) Corrosion

[: defined as a surface with light to moderate corrosion damage to the paint surface]



2. Stage II (Sub-surface) Corrosion

[: definition when the dirt/corrosion deposits are no longer on the surface but have started to break down the molecular structure, leaving an etched or white haze on the surface( a concave circular mark ) after the stain has been removed, with moderate to serious paint damage]



Drying a Vehicle using water



Sheet the water by using a gentle flow of water direct from the hose (without a water nozzle) starting from the top downwards, and then use a water blade on the glass surfaces. Remove the water from the paint surfaces with a blower, again from the top downwards and then finish off with a waffle weave towel and a drying / lubrication aid (Dodo Juice -Time to Dry) diluted 1:1 with distilled water



Water sheeting (Marangoni Effect)



[: since a liquid with a high surface tension pulls more strongly on the surrounding liquid than one with a low surface tension, the presence of a gradient in surface tension will naturally cause the liquid to flow away from regions of low surface tension]



This is my preferred method of drying a vehicle paint surface; on the final rinse of the washing process remove the nozzle from the hose, reduce the water pressure and hold the end of the hose parallel to the paint and reasonably close as this is will prevent splashing as you flood the surface; this drying method helps to eliminate water-spotting. Use a forced air blower to remove water residue and then follow up with a waffle weave micro fibre towel to thoroughly dry the paint surface



I have tried many products over the years for drying but I finally found what really works the best, a micro fibre waffle weave drying towel. When they are wet they’re very soft and super absorbent, and glide easily over the surface, the ‘pockets’ in the weave ‘hold’ any dirt or surface debris unlike some other super absorbing products that trap dirt between the towel and paint surface with the potential to cause so serious scratches (never use it when it’s dry and stiff – it can potentially scratch) Wet –Wring- Wipe



That goes for whatever you use for drying, including waffle weave micro fibre towels. Ensure that the towel is really wet and then wring it out thoroughly before using. Blot as much water as you can, do not rub with the damp waffle weave towel. This gets rid of all the remaining drops and leaves only a little moisture behind. One wipe with the waffle weave in your other hand will result in a perfectly dry paint surface, using only waffle weave micro fibre towels with only one pass per area.



Waffle Weave Towel - a waffle (Piqué) weave towel is a synthetic micro fibre woven with a dimpled pattern, which much like an open-cell sponge provides thousands of small pockets to trap dirt or grit. The absorbency of these towels is quite remarkable; they are able to hold seven or eight times their weight in water. Instead of wiping with your waffle weave towel drying towel, blot the paint to minimize adding imperfections



Drying methodology- provided the paint finish has been rinsed adequately (See Drying a Vehicle ‘sheeting’ water) there should be no dirt residue. Water is a good solvent but a very poor surface lubricator. Try using a drying aid type detailer like Dodo Juice USA Time to Dry diluted 1:1 with distilled water, which provides lubricity to the paint`s surface, in tandem with a damp waffle weave towel (wet, wring and then wipe) when drying your car - this will help break the surface tension of the beads causing the water to run off, allowing the towel to soak up more, and minimise water spots while lowering the friction of the towel over the surface.



Take two waffle-weave drying towels; one soaking wet (a wet towel wicks away more water than a dry towel) and one damp. Wring out the wet towel and use it as your primary drying towel, use this towel to blot- dry and check and rinse the towel often. Wring it out as you go, this will leave smaller wet streaks, which you can remove with your damp towel and it should leave a ‘streak’ free paint surface. This drying technique is excellent for black cars (including ‘soft’ single stage paint that shows every surface mark) but look so good when they are properly detailed.



This process never includes scrubbing, rubbing or applying any pressure whatsoever. The only time that pressure needs to be applied to a paint surface is when you are polishing.



Alternative - dry the car using a surfactant type (ONR) detail spray (8oz / gallon) and a waffle weave micro fibre towel. Why? A surfactant encapsulates any dirt and will provide lubricity to the paint`s surface as you blot the paint to minimize adding imperfections. This method will safely remove any water spots that might occur



GP Micro Drying ultra soft waffle weave towel this towel also has a soft foam core that softens the pressure applied to the paint surface. This minimizes those pesky holograms and swirls that result from pressing too firmly on the paint finish.



Drying Paint Surface Techniques



If you’re using softened water I see nothing wrong with using an electrical leaf blower dry off your car (just be careful not to bump the hard plastic nozzle against the paint) but if you live in an area that has hard water, it seems that you’d only be accelerating the evaporation process and that those harmful and often damaging alkaline minerals that cause ‘water spot’ damage, would be precipitated out as the water evaporates and must therefore be collecting somewhere, in the seams or crevices perhaps?

Starting at the roof and then blow out the mirror housing and then work your way down the body (make sure the driveway is free of any loose dust/grit or debris) blow out the light housings and licence plates before you start on the back of the car. Finally the wheels and callipers (ensure that the wheel surfaces are free of brake dust particulates)



Water Blade:



The best-known US brand is The Original California Jelly Blade 2010 Version (equivalent UK Autoglym Hydra-Blade) is made of medical-grade silicone, which is very soft and flexible; it will not scratch the paint in and of itself. It can be used to remove water after washing the vehicle without causing scratches by applying very little surface pressure with the blade, wiping with long strokes in one direction only.



If there is any grit left on the car after washing, the blade may pick it up and drag it across the paint, much the same as a towel would, this can be avoided by wiping the blade with a clean damp towel after every pass.



The water blade should be protected when not in use. If it is crushed in storage, the edge may take a set and leave a stripe of water on the car, the water blade comes with a protective plastic case, use it for blade storage.

Like any tool, the water blade does require a little bit of technique and practice. The first few times I used mine, it tended to chatter on the surface, resulting in incomplete drying. It turns out this is eliminated by using just the right angle, and pressure on a wet blade. Smoothness can also be affected by the surface condition of the paint (wax, sealant oxidation, etc.) and any coating that might be on the water blade itself.



I will add that I now only use this tool on glass surfaces, but that’s just over cautious OCD me



Caution: do not use a water blade to remove rainwater as there could be road grit on the paint surface or the rain may contain impurities that could scratch the paint.



The Air Wand is a high-velocity air nozzle that blows air up to 200 M.P.H. to remove dirt, dust, water, leaves, grass (or any other unwanted non-adhered material) from surfaces and hard-to-reach areas. The Air Wand greatly accelerates nature`s drying action with no adverse effects to existing fragile finishes and delicate surfaces. It saves time and cares for your prized possessions. Simply attach the new Air Wand to the blower and dry the vehicle in a fraction of the time and with less effort - Air Wand - Description (http://www.airwand.com/description.htm) (approx $100 - 11/09)



The Airmax Two-Speed Filtered Dryer is a dual motor air blower capable of delivering 266 cubic feet of air per minute. It filters the air before it is blown out, assuring you aren’t accidentally sandblasting your paint surface while drying your car. Taking it one step further, the air is also heated 40.oF above ambient temperature, to accelerate the evaporation process and dry the car even faster. It is basically a 27,000 rpm, dual motor dryer, it makes the process easier, faster, and completely eliminates those persistent drips for good.








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Accumulator
07-31-2011, 11:50 AM
Another great read. Many people claim that Water Blades scratch paint even when the surface is clean. Has anyone made any definitive analysis of this? I woujld really love to try one if indeed it did work.



While my experiments weren`t all that scientifically rigorous, I found that the blades of my CWBs would not mar the paint on *my* vehicles, the softest of which is an `85 Jag (single stage lacquer) unless I concentrated the contact pressure in an unnatural way. But a) that doesn`t mean they wouldn`t have scratched *your* paint if it`s softer, b) it might be easy for somebody to inadvertently duplicate that "unnatural contact pressure", and c) even cleaning the blade between swipes is an imperfect solution (to the "grit between CWB and paint" problem) as any grit that you clean off will have probably already marred the paint to some extent.




If you’re using softened water I see nothing wrong with using an electrical leaf blower dry off your car (just be careful not to bump the hard plastic nozzle against the paint)...



IME it`s best to follow up the blowing with some sort of QD/ONR wipedown; the residue from softened water isn`t nearly as bad as that from hard water, but it`s still something I don`t like leaving on the paint. Of course the severity of that residue will depend on how bad the water was before softening (the whole ion-exchange thing) and the effectiveness of the softener, and probably some other factors I`m not thinking of.



The "blowing only" drying can work fine with deionized water, if you somehow get all the "regular water" out of the nooks and crannies.

Bill D
07-31-2011, 12:01 PM
The "blowing only" drying can work fine with deionized water, if you somehow get all the "regular water" out of the nooks and crannies.



It can, but I haven`t been able to remove much more than about 95% of the water with my Air Wand ( which is a true godsend when it comes to shaving down washing-drying time). I might still be getting my technique down. I get water out of tight spaces like seams and rearview mirror recesses with a mini blower, and I follow up with QDing and drying the very small remainder with a WW MF.

Accumulator
07-31-2011, 12:12 PM
Bill D- The efficacy of the AirWand with regard to getting all the water off can depend on sooo many things, such as the LSP, the contours of the vehicle, and yeah..your technique. FWIW, I find that holding it in the seemingly obvious manner (gripping the handle like a hammer) is a really bad approach, at least for me. Covering part of its output slot with your free hand can help concentrate the airflow to some extent, but yeah, I still have to follow up w, with something better suited to tight spots.





At least with DI water any leftover moisture can evaporate cleanly.

togwt
07-31-2011, 01:10 PM
Another great read. Many people claim that Water Blades scratch paint even when the surface is clean. Has anyone made any definitive analysis of this? I woujld really love to try one if indeed it did work.



The blade is preceded by water, much like detailer’s clay; this cushion of water should protect the surface against scratches, especially if you use a drying aid (Dodo Juice USA Time to Dry) to provide surface lubrication