Cleaning glass, as simple as it sounds, is actually quite difficult and can be very frustrating. There are a few reasons for this. First and foremost is the fact that glass is so easy to inspect…being transparent, it is too easy to critique its cleanliness!! But why is it so hard to get glass clean? First up is towel choice. Often overlooked but absolutely essential is the choice of cleaning towel…more often than not, paper towels are used and this will certainly yield bad results. Second, product choice is very important. Typical glass cleaning products don’t do a great job…they clean glass to a point of ‘satisfaction’ but don’t really get glass clean – at least not to the discerning eye of the ‘detailer’. And, third, the method one uses to clean glass often contributes to less-than-satisfactory results. We will look at each of these individually below…but first, how do you know when glass is clean?
More often than not, once you finish cleaning glass with a typical glass spray and towel, it will ‘look’ clean from one angle but yield streaks/hazing/smearing etc. from another angle – especially when the sun shines through it or light reflects off of it. Hence, the easiest and most obvious way to know if glass is clean is to thoroughly inspect it if from many different angles using different lighting sources. Keep in mind that glass attracts contamination quite readily. Waxes, silicones, oil, dirt, dust, grime, etc. adhere to glass and removing these contaminants with typical glass cleaners usually results in movement of the contaminants across the surface rather than truly removing them from the surface. In the end what’s left behind are streaks! There are products that are formulated in such a way as to leave a streak-free surface but, for some reason, they aren’t very well known or at least aren’t typically used for cleaning glass. Two such products that we will discuss below are Original Bon Ami Powder Cleanser (or Bon Ami Cleaning Powder) and Gel-Gloss NoStreek.
(Quite interesting is the fact that clean glass should not bead water – if you spray water on glass it should sheet off. After glass is cleaned using typical products/methods, however, it tends to bead water! If the water beads (forms drops) then there is some sort of contamination remaining on the glass as a truly clean window will not bead water. Keep in mind that some glass cleaning products do contain a wax to add brilliance to the glass after it is cleaned and this wax may cause the water to bead even though the glass is clean.)
Choice of Glass Cleaning Towel
How often do you see people cleaning glass with household paper towels? Your choice of cleaning towel is more important than you might think. Don’t use paper towels! The reason? Paper towels are abrasive and contain dyes and adhesives that will undoubtedly leave streaks. In addition, paper towels leave lint. The picture below shows that paper towels actually consists of two thin pieces of paper towel that are glued together with an adhesive. When you clean windows with paper towels, the glass cleaning product breaks down the adhesive and it causes smearing.
A better choice of cleaning towel, but not the greatest, is a microfiber towel. I say ‘not the greatest’ because microfiber towel quality tends to vary from vendor to vendor. In general, a quality microfiber towel (e.g., DF Concours) will yield clean glass provided you exercise some patience. Microfiber towels are not abrasive and do not contain adhesives but you may be plagued with lint depending on your choice of microfiber towel. If microfiber towels are all you have then don’t fret – you should still be able to achieve good results.
To obtain the cleanest glass possible, however, you should use ‘surgical towels’ or ‘huck towels’. Surgical/huck towels are 100% cotton, are great for glass surfaces, and they will not leave any lint! In addition, they are absorbent – especially once they are broken in – and are also relatively thin. Surgical/huck towels can be purchased here, on eBay, or through other online retailers. Just make sure that the towels are new – used towels are not recommended.
Irrespective of what towels you use, microfiber towels or huck towels, it is imperative that you dedicate these towels solely to glass cleaning and that you wash them separately of all other towels. It is good practice to get some Ziploc bags or plastic containers to help you keep your towels separate from each other. When you wash your towels, avoid the use of fabric softeners and powdered detergent. Simply wash your glass cleaning towels independently of all other towels with liquid laundry detergent (e.g. Woolite) and they will remain clean and last a long time.
Choice of Glass Cleaning Product
Let’s talk for a moment about typical glass cleaners. From a consumer’s point of view, ease of use is very important…often essential – at least that is what sells. If you walk up to a consumer with a great glass cleaning product that is ‘hard’ to use…I can assure you that they aren’t going to use it. For this reason, the bulk of glass cleaning products come in an aerosol or spray. The Clean Air Act , however, requires the Environmental Protection Agency (EPA) to regulate the emission of Volatile Organic Compounds (VOC) in consumer products (necessary to limit the formation of ground-level ozone) – to include glass cleaners! Most (if not all) glass cleaners contain isopropyl alcohol (which is organic) and by limiting the percentage of isopropyl alcohol, the cleaning effectiveness of these products, over time, has diminished. It may be possible to obtain a clean, streak-free finish using typical glass cleaning products but I can assure you that it is difficult and will take a lot of effort – you can get satisfactory results but not the best results. In order to achieve a truly clean glass, I am convinced that you have to get away from spray- or aerosol-type products. With that said, let’s discuss glass cleaners.
ClearVue Auto Glass Cleaner, Sprayway, Stoner’s Invisible Glass, 3M Glass Cleaner, Meguiar’s NXT Generation Glass Cleaner, Auto Magic Glass Cleaner #64 – and the list goes on – will all do a decent job at cleaning glass, so take your pick! What ever product you use, follow the manufacturer’s directions as some are concentrated and require dilution prior to use. Two things to keep in mind…multi-surface cleaners are a big no no and glass cleaners with ammonia should be avoided – ammonia is especially bad for tinted windows! All of the glass cleaners I just listed are usually easy to find and come in an aerosol can or spray bottle (these are what I refer to as typical glass cleaners). There are two additional products that will yield phenomenal results: Original Bon Ami Powder Cleanser (or Bon Ami Cleaning Powder) and Gel-Gloss NoStreek. Bon ami can usually be found in your local supermarket or you can order it online. NoStreek is a bit more difficult to find (you can try your local Ace Hardware) but I guarantee that you will not be disappointed. NoStreek it is truly the best glass cleaner that I have found after years of looking!!!
Glass Cleaning Method
If you are using an aerosol or spray bottle cleaner…
- Cleaning glass properly requires two towels (and sometimes three) – one for cleaning /agitating and one for drying/buffing (and perhaps a third to buff once more). Take two towels, preferable huck towels (but microfiber towels are ok), and fold them (into quarters) so they are a bit larger than your hand. These towels should be dedicated glass cleaning towels!
- Spray the entire glass area and then agitate with one of your folded towels making sure you get into the corners…it’s best to outline the glass first and then move to the center. When you complete the whole glass simply wipe/buff it dry with the second towel. If you are cleaning side windows, it’s good practice to first roll the window down a bit to get clean the edges…then roll it up and do the rest. After you buff, if you have third towel available, buff again! You will need to do spray, buff, and buff again fairly quickly so that the product does not dry on the window by itself.
- When cleaning your glass, make sure the towels do not get bunched up in your hand. Having a flat towel that contacts the glass evenly is your best choice, for both cleaning and drying. If you drop a towel…put it to wash, don’t use it!!
- After you complete one piece of glass, re-fold your towels and proceed to the next window – repeat steps 1-3 until all of the windows/mirrors are complete. Make sure you use the same towel for cleaning throughout the whole process…and likewise, the same towel(s) for drying/buffing.
If you are using Bon ami powder…
Original Bon Ami Powder Cleanser or Bon Ami Cleaning Powder will yield great results. At first glance, considering this product is a powder, one may fear that its use on glass may cause scratches. Bon Ami Powder, however, can be used to clean glass provided that it is used with care. Do not use Bon Ami to clean interior tinted windows!!! Provided you are using the powder version of Bon Ami, following these steps will yield very good results:
- Before cleaning the glass with Bon Ami, simply clean the glass with soap/water and/or a quality glass cleaner to remove any loose surface contamination. While this step is not critical, it will yield a better end result.
- Take a microfiber towel, thoroughly wet it, and then wring it out so it is just moist.
- Fold it in quarters and put some Bon Ami powder on the corner of the towel and then smooth the powder into a paste with your finger – make sure all of the powder is dissolved. This step will guarantee that scratching doesn’t occur.
- Now clean the glass/window with that towel – just move it around on the glass in circular motions making sure you cover the whole window.
- Now take a dry microfiber towel and wipe the residue away so that you are left with a clean, dry window.
- Finally, take another microfiber towel or, better yet, a Huck towel, and wipe it once more paying attention to any residue.
- After you complete one piece of glass, re-fold your towels and proceed to the next window – repeat steps 1-6 until all of the windows/mirrors are complete. Make sure you use the same towel for cleaning throughout the whole process…and likewise, the same towel(s) for drying/buffing. You will most likely have to add more power after each window.
If you are using Gel-Gloss NoStreek (by the way, this is the best method)…
I will state once again, Gel-Gloss NoStreek will yield the absolute best results of any of the methods/products listed above…and it is very simple to use!!
- Simply take a foam pad (like the one you would use to hand wax a car)…shake the bottle of NoStreek very well…put a few drops on the pad and work the product into the glass using circular motions. As with the other methods, pay attention to the corners.
- Let the product dry on the window (it will haze).
- Once it dries, take a huck or microfiber towel and buff it off…that’s it!!! The window will probably be the cleanest you have ever seen it. If your windows are extremely dirty then just repeat the process.
I have spent years trying to find the best method and the best product to clean glass without leaving streaks behind. I actually stumbled across NoStreek in an Ace Hardware store…and I have never looked back. It is just one of those products that you can’t do without!!! If I can say anything negative about NoStreek it is the fact that it contains small amounts of ammonia and, hence, is not recomended for aftermarket tinted windows (see below Tips/Comments).
Water Spot Removal
The dreaded water spot! Water spots are actually areas of dried mineral deposits that remain on a surface after water is allowed to air dry…over time they will etch their way into the surface (whether it be clearcoat or glass). The best way to avoid water spots is to dry your car each and every time it gets wet…often this is not possible, especially after rain, but after washing a car, drying is an absolute necessity. If you are already plagued with water spots on your windows then there are a few things you can try.
In some cases, water spots can be very difficult to remove. A word of caution…do not use steel wool to clean your windows! Even 0000 (4-0) steel wool can cause scratches on glass if not used properly. As with all aspects of detailing, begin with the least abrasive method first…this would be a glass cleaning product along with some huck towels as described above. Assuming you have tried this to no avail, proceed to using a different product such as an All-In-One (AIO) (e.g. Klasse AIO, Zaino AIO) or a stronger glass cleaning product such as Clear Difference (#43) by Auto Magic or Zaino Z-12 Clear-View Glass Polish. These products should be able to remove the worst of water spots. You may also be able to remove water spots with a huck towel and some vinegar…give it a try, you will be surprised at how well vinegar works. Of course, NoStreek will probably do the trick – I wouldn’t be surprised if it did!
- All cleaners evaporate quickly when used in direct sunlight so either wipe quickly or move to the shade when cleaning glass.
- Some people do not spray the glass itself, but they spray the towel. This method has the benefit of reducing overspray on other areas of your doors and dash.
- To strip an extremely dirty window of smoke residue, grime, etc you can use alcohol and water in a 50/50 mix or a vinegar/water mixture. You may need to let the alcohol/water or vinegar/water dwell a bit but they should do wonders in cleaning your glass. Once you get the bulk of the glass clean you can then use your regular glass cleaning product.
- Glass, like most parts of a car, may get scratched over due time. There are dedicated products on the market for polishing glass. I have not used these products directly so I can’t recommend them. The Eastwood Company makes such a product.
- Do not use ammonia-based window cleaners on windows that have an aftermarket tint film applied to the window. Aftermarket tinted windows contain either dyed or metalized (or both) films that are applied to window glass with an adhesive. Ammonia will dissolve the metals within window film and, over time, cause the film to degrade. In addition, the ammonia will dissolve the film adhesive. Factory tinted windows are not normally affected by ammonia as the tint is within the glass and not on the surface. Keep in mind that NoStreek does contain small amounts of ammonia and is not recommended for use on the window film.