Water spots take many different forms across the various surfaces on your vehicle. The two most common (and frustrating) are the spots left behind on your paint and glass. Let’s take a few minutes to talk about what causes water spots, how to remove water spots, and finally, how to prevent water spots.
What causes water spots?
Water spots are most frequently created when hard water is left on a surface – paint or glass – to dry (technically, evaporate). This can be due to not drying your car after a wash (especially if your TDS level is high – more on this later), parking your car a little too close to a sprinkler, or even from rain water that is left on the surface too long. In a best case scenario, the minerals and dirt in the water are simply left on the surface of the paint after the water has evaporated off. Things get worse if the water contains something corrosive that etches the surface as it sits, creating a “crater”. If not addressed, these craters can actually get worse over time, as water will pool in them and continue to etch the same spot.
How do I remove water spots?
Depending on the severity, there are a few solutions to removing water spots. As always, you’ll want to begin with the least aggressive product necessary to get the job done. So, start with the basic things. Clean the surface; this can be with Car Wash, Speed Shine®, Window Cleaner, or whatever product is appropriate for the level of dirt on the surface. Often a simple cleaning will remove some of those basic water spots caused by dirt or minerals sitting on the surface.
If a basic cleaning doesn’t cure the problem, clay is your next level of attack. Depending on the surface, choose paint, glass, and/or wheel cleaning clays. These will still attack dirt and minerals, and they’ll be more effective at pulling things off the surface that have been around for awhile and bonded to it. Give a light mist of Speed Shine and gently rub the clay across the surface (see a video demonstration) to pull the contaminants from the paint. This is a non-abrasive process, so extra applications are not going to hurt.
Okay, so cleaning and claying haven’t removed your water spots; you’re most likely dealing with spots that have etched into the surface. Don’t stress! A little polishing should take care of the problem. Here are two videos that will give you some tips on picking the right polish and some techniques for applying it properly: Video One | Video 2
How do I prevent water spots?
Simply not getting our cars wet is not an option for most of us, so let’s talk about realistic ways to reduce the likelihood of water spots forming.
First, a good coat of wax or sealant on your paint is the first line of defense. Not only will this prevent most spots from occurring in the first place, it will create a barrier between the hard water and the paint. So, if a water spot does form, it will most likely be on the wax/sealant layer instead of the paint making it much, much easier to remove.
Second, keep your car clean. I can’t stress this enough. No matter how hard we try to avoid it, rain will fall, our cars will get hit by a poorly aimed sprinkler, and unwanted water is going to end up on our vehicles. As we talked about earlier, it’s not the water that causes spotting; it’s allowing what’s in the water to sit on the surface. Keep some Spray-On Car Wash on hand and don’t delay washing your car (though, as mentioned above, staying current on your wax/sealant will slow down the “rush” of getting the car clean before spotting occurs).
Lastly, rinse with pure water. Average tap water ranges anywhere from 140-400ppm total dissolved solids, or TDS (measured as the amount of mobile charged ions, including salts, minerals and metals, in a given volume of water). Water is considered “hard” anywhere above 170ppm, so there’s a good chance you’re rinsing your car with hard water. You can measure this with a good TDS Meter.
Even if you’re quick with the drying towel, sometimes the minerals can be quicker. Filtering them out of your water (no need to do this during the wash… save your filter for the final rinse before drying) will prevent minerals from sitting on your paint and glass.
Which water filter is right for me?
At Griot’s Garage, we offer two different water filters; our In-Line Water Softener and our Portable Water Deionizer. Both are going to be effective at filtering the water, but there are a few cost and usability differentiators.
The Portable Water Deionizer is the best, no question. It comes on a roller caddy, has easy-to-use on/off valves (to switch between tap and filtered water) and, in the long run, is the more cost effective filter.
Our In-Line Water Softener is also a great choice, and better for the user that doesn’t have overly hard water or isn’t sure he’ll be using it that often. It includes quick-release fittings on each end that allow you to install and use it without having to thread it on and off, but it will require turning the water off during install. Simple, just not as quick and easy as the Portable Water Deionizer… This is one of those “good vs. best” scenarios.
I’m a numbers guy. Let’s break down the cost difference; I’ll use a best-case 100ppm and worst-case 400ppm example. To give you price points, our Portable Water Deionizer runs $370.00 with each refill being $89.99. The initial cost of In-Line Water Softener is $129.99 with refills running $109.99.
With a TDS level of 100ppm, the Portable Water Deionizer will filter 705 gallons of water before needing a refill. Filtering the same water, you can expect 198 gallons from the In-Line Water Softener. To take into account at least one refill of each, let’s look at the cost of filtering about 1,400 gallons of 100ppm water.
Now, let’s assume you’ve got really hard water measuring 400ppm. In this case, you can expect the Portable Water Deionizer to filter 176 gallons before needing a refill. The In-Line Water Softener will only do 49 gallons. Again, to take into account at least one refill of each, we’ll look at the cost of filtering about 350 gallons.
So, as you can see, it is about 42% cheaper to use the Portable Water Deionizer, but only using it for a few gallons per wash (remember, it’s only needed during the final rinse), it would make sense for some people to use the In-Line System since they may not need to refill too often.
Now you’re armed with all you need to know about water spots (maybe more!). If I’ve overlooked something, you’d like some clarification, or you’ve got some water spot tips of your own, please share them in the comments!
Have fun in your garage!