Polishing Your Glass
Your glass is just another surface on your vehicle that can be polished just like your vehicle's paintwork. Polishing your glass can be a fantastic way to give it a super clean as well as remove minor defects while improving its clarity and look.
Why Polish Your Glass?
There are a variety of reasons why you should polish your glass to remove any imperfections and scratches.
- From a safety perspective, stained, contaminated and foggy car glass can largely mask your ability to clearly see the road. Keeping your glass clean, clear and free of any imperfections can prevent possible incidents due to a lack of clear vision on the road.
- Stubborn defects such as water spots, bird poo etchings and minor scratches or swirls can also be removed when polishing your glass. This will greatly improve its visual appearance.
- Polishing your glass will also help remove more embedded grime, which can happen over time when the glass is not regularly cleaned or well maintained.
- Giving the glass a polish prior to applying protection, such as a ceramic coating, will massively increase that coating's performance and durability.
(ShineMate ERO600 9mm DA Polisher)
How to Polish Glass
Glass specific polishes use fine abrasives, usually cerium oxide, to remove day to day environmental buildup, staining and water spots. Glass is far harder than paint, so the abrasives in a normal paint compound tend to skate across it rather than cut, which is why a dedicated glass polish does the job so much faster.
CARPRO CeriGlass is the one most people know, a heavy cerium oxide polish for water spots, wiper haze and light scratching. CARPRO GofX is the newer option and it does two jobs at once, cleaning and polishing in the same step, so it's the quicker choice for maintenance work and lighter contamination. Shine Supply Glass Polish sits alongside them as a straightforward machine or hand polish.
Although you can certainly hand polish automotive glass, it will tend to be a far quicker and more effective process using a DA or rotary car polisher.
When polishing your glass you must ensure the glass has been washed first. The actual process is very similar to polishing car paint, in that you'll apply a small amount of your polish to a pad and run your machine, or hand pad, over a section of the glass using three to four passes to complete each section.
You'll then use a glass cloth to wipe the polish residue off, followed by a panel wipe or a glass cleaner to remove the polishing oils and any lingering residue. Around the edges of the glass it will be more effective to use a mini polisher with a smaller pad, or to polish those tight edges by hand with a hand applicator.
It's also important to note that the interior side of the glass can sometimes be far dirtier than the exterior, particularly if it isn't regularly cleaned, in which case it develops a yellowish film of grime. The same process works on the interior glass. If the glass is tinted, avoid abrasive polishes on the film side and stick to a non-abrasive glass cleaner.
In cases where the exterior glass is heavily contaminated with water spots, etching or fine swirls, a rotary polisher with a glass polishing pad and a cerium based polish is best, and you'll need to work smaller sections at a time to get results.
Once the glass is completely polished and clean, it's best to put a specific glass sealant or coating on it to protect the finish and keep the glass cleaner for longer. Something like Nv GLASS is made for the job, whereas certain generic sealants and coatings can lead to wiper chatter in the rain.
What to look out for when Polishing Glass.
Glass is extremely hard compared to car paint, and takes a lot of time and work to remove defects.
Due to that hardness, minor swirls can be removed, while more significant swirls and scratches will need the specialised diamond cutting discs used by a dedicated glass repairer to have any success.
The upside of that hardness is that you're very unlikely to haze or mar glass the way you can with paint. The one thing to manage is heat. Glass is rigid with little flex in its structure, so concentrating heat in one spot can damage it. Keep the surface misted with water, keep the pad moving in overlapping passes, and stop and check by hand if the panel feels warm. Don't polish over an existing chip either, get it filled first.
(What else should I know about Polishing Glass?
The best way to maintain glass is with regular light cleaning to prevent the buildup of environmental grime. The use of a specialised glass cleaner and a microfibre cloth will make this so easy, and extremely effective.
Although glass is harder and more scratch resistant than paint it can still scratch, so always use safe car washing methods on your glass as well.
Work under good light. Glass defects hide under ambient light and show up under a detailing light held at an angle, so a Take Now handheld or a 20W on a tripod is what tells you whether you've actually removed something or just moved the polish around.
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