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I recently asked about having my coating re-applied, and the folks at the eye place had a warranty system, where if it came off inside of two years, they'd strip and re-coat the lenses. Might call them to find out if you're covered, or of they can tell you the stripping method.
If the lenses are plastic acetone will fuck them up.
Alcohol would, too. Further, avoid mineral spirits and petroleum based solvents entirely.
Alcohol has never affected my plastic lenses.
There are some plastics it affects, I've just never seen it affect glasses. Notably, the eyeglass cleaner kits at eyeglass shops are alcohol based.
Alcohol will affect acrylic/plexiglass, but its not necessarily a fast reaction. I don't know what specific plastic glasses lenses are made of. Also, the UV coating might protect them from the alcohol.
Pulling this straight out of my ass but I think it’s likely to be polycarbonate
I worked in optical it's polycarbonate. Can be a plastic called cr39 or it could be a high index lens if they have a very high prescription generally alcohol won't hurt it. If the frame is plastic the alcohol could potentially fog the plastic.
Makes sense, given alcohol comes in plastic bottles
Nah they're glass, besides, I tested acetone on a small spot and it did nothing to remove the coating
If it is anything like the polycarbonate lenses on cars, it will take extremely tedious polishing, and then you'll have continuous issues with yellowing because polycarbonate is not UV stable.
With my auto body shop, I sanded the lenses to 2000 grit and used a polyurethane clearcoat. However, typical automotive clearcoats are not optically perfect. It does not matter with an automotive headlamp, and 99.9% of people will never see the optical properties unless I pointed them out specifically. That said, coatings like automotive clearcoats are designed to adhere to very specific types of substrates. What I was doing was WAY outside of the intended use. I doubt any of the lenses I clearcoated lasted more than 3-5 years as a result.
The PITA part of clearing lenses like I was doing with headlights is that ALL of the old coating must be removed first. If I didn't sand off every last bit of that coating, it was very noticeable in the final outcome. I had some tricks, but it is not possible to use course grades of sandpaper that would make fast work of it situation but require a primer to level in a typical body shop situation. This meant I had to start with 1k grit. That takes FOREVER to sand through a coating like what headlamps have.
Sanding anything like this is not compatible with optical precision lenses. I have also played with telescopes and building my own eyepieces while also dreaming about grinding my own mirror for a large dob. Optical precision in lenses is OP insane levels. I don't have the vocabulary to express just how tiny the difference is between good, okay, and absolute trash in optics.
Combining my experiences in these areas, there is absolutely no chance that you'll be able to polish or abrade then polish an optical lens and yield an acceptable outcome. No matter what you try, the coating will abrade/polish at a different rate than the exposed sections of the underlying polycarbonate lens. This will always result in an uneven surface at optical quality kinds of levels. You would need a sanding block capable of matching the contour of the lens perfectly so as to only abrade away the coating section before contacting the lens.
While clearing headlamps, I had one of two tricks. If all I was doing is shooting the lenses, I would mix my clear without any additional reducer (special solvent) and with a fast catalyst. This required special gun settings and higher pressures to avoid orange peal textures. If I was mixing clear for other panel work, I had to do a few misting passes with clear in between my other panel work. The thin misted coating limits the exposure of the underlying polycarbonate to the solvent present in the clear. If I did a regular wet pass like I would with a panel, the lens would react to the solvent and looked like a shattered windshield.
I don't know of anyone else that has ever clearcoated headlamps like this. While my work may not have lasted as long as a typical clear, it was a far better solution than polishing, which reoxidizes within a few weeks and worse with the increased exposed surface area after each polishing. For higher end cars, dealers would just pay me to install reproduction headlamps from LKQ, as these will last like the originals or better.
Those are the basics of what I know. I shared as an abstract way to help you understand the scope of what I know, and what you should expect based on this tangentially related expertise. I do not believe you can be successful at removing that coating. In automotive paint, it is not possible to just remove a clearcoat from any surface chemically without impacting the deeper substrate.
Wow, great info, lots of detail. I'd enjoy watching you work!
Just an FYI, I had that happen to my driving glasses a couple years back. My optometrist said that's because you cannot leave glasses in a hot car as the heat destroys the coating... OK thanks for telling me AFTER the fact, where do you THINK I am keeping a pair of glasses that you designed specifically for my driving vision? And by the way, I've been wearing glasses for over 35 years and always had the anti-glare coating for night driving, what did you change that is suddenly making them self-destruct when they are stored where I need them???
Yeah they had no answers for me. But OP, if you left your glasses in your car, that's probably what happened to the coating.
Just an FYI, temperatures in a car in direct sunlight can exceed 165F. Very quickly.
I know this because I left a glass thermometer under my seat for an hour one summer. When I came back to grab it, the glass has burst (max on the scale was 165F).
I have no idea about lens coating changes over time and their heat tolerance, but the insides of cars can be fucking awful.
That's 74 degrees Celsius for the rest of the world
Oh I agree it can be a friggin' furnace. My complaint was that I'd never had that happen before so why is it happening now? And if I can't keep my driving glasses in my vehicle, where am I supposed to keep them? Maybe keep them at my desk just in case my monitor suddenly gets really far away?
Could have something to do with global warming.
I'm sure that's the case for a lot of people, however my particular locations has actually been getting more temperate -- cooler in the Summer and warmer in the Winter. I mean it's not by much, but we're lucky to not be getting these massive heat waves the rest of the country has been seeing.
I saw a guy on YouTube a few years ago, heat water in the car to temperatures hot enough to brew coffee, which he then went ahead and did. It was a cool video. I doubt I'll be able to, but I'll try to find it. Anyway, yeah, cars are super hot in the sun.
Edit: I found it, searching for 'brew coffee in your car', so simple haha. Holy crap! 6 years! He hasn't posted anything in a long time. Hope he's ok...
No but I did take a trip to the deep south, Kentucky is a killer this time of year
Ugh I bet.
Specialists can be so stupid. I think doctors don’t get enough sleep. Somehow they end up extremely disconnected from their customers’ actual needs.
Blows my mind that they wouldn’t think to tell you this. Why wouldn’t they have a checklist of things to cover? Any appliance salesman is going to have a list of things he tells you when you’re packing up a new dryer to take home. Why is that schlub taking his job more seriously than a doctor?
I honestly don’t get it. Part of me suspects the white lab coats interfere with a sense of shared experience. Kinda like the doorway effect, but with clothes.
You're overthinking this. Company decided to cheap out to raise profits, so they changed the formula for something that will last X years instead of XX years and hoped no one would notice.
I have worked in optical, that coating is the anti-reflective coating that is coming off. You cannot take that coating off. It is baked on. Harsh chemicals will destroy the plastic lenses. It just degrades and comes off after a while, generally if it is less than 2 years they should be under warranty.
The really annoying thing is that these coatings used to be optional paid extras, and when I got some new lenses for the first time in almost a decade they quickly became blotchy and awful so I went back to get some more but this time with zero coatings.
Specsavers told me that's wasn't possible, that ALL lenses have these coatings now, it's not even optional.
Glasses lenses used to last years and years, now they're blotchy crap after only 3 or 4 years. Bloody ghets know what they're doing. And ripping us off while they're at it with their high prices £££
Thankfully it is glass, I may just have to take this to an optometrist and see if they can do it for me
I've had good results removing the coating with armor etch, but be warned that the uncoated plastic lens are now more prone to scratches. I was able to extend the life of my glasses about 6 months before I got annoyed with the microscratches building up, was able to save up for a new pair.
Next time ask your lenses without. Mines are the same, I have a new prescription & just told the shop "no". No anti-blue, no ant-reflection, no nothing, just the hardest material available.
Antiglare coating is a must for me. There’s a reason it’s used on lenses in cameras; it enhances contrast, and for purely aesthetic reasons, makes it easier for others to see your eyes, making you look better.
High index plastic is also great IMO, it significantly reduces the thickness and weight of the lenses. Also aesthetically, it reduces the distortion of the sides of your face when someone’s looking at you. It is not the hardest material available, and I believe the higher the index, the less hard they are. My lenses are typically completely scratch free for a year or two, getting only minor scratches after that.
I’ve never had an issue with coatings. I clean my glasses with hot water and Kimwipes (laboratory lint free wipes). I don’t use any lens cleaners or any other cleaning products. I never dry wipe my lenses.
Hot water and excessive heat from cooking can crack the coating.
I haven't read the manual but I don't think you're supposed to cook your glasses.
I’m not taking about boiling, just hot out of the tap. It helps gently heat the lenses so they dry faster after being wiped.
Unfortunately that wasn't an option at Walmart the last time I got glasses. I wanted to go to my old eye doctor instead of Walmart, but that was during the COVID lockdown shit and I would have had to wait like 3 months.
Sigh, this coating shit sucks ☹️
In the future, I highly recommend using Kimwipes to clean off your lenses day-to-day. They're little papers designed to wipe off lab equipment without leaving any scratches or residue, and you don't need to spray them with any cleaner either. Just a dry wipe until the lenses are clean. If I'm careful about how I use them, a wipe can be reused 2-3 more times before disposal.
Since I started using them, I've never had problems with the antiglare coating coming off.
Half of the picture is blurry, put them back on!
Toothpaste with hydrated silica might polish it off with enough elbow grease. Should be gentle enough to not fuck with the polycarbonate lens itself. I've done it with success but the toothpaste I used was an institutional brand and not really fit for putting in one's mouth.
Commercial toothpaste with hydrated silica would be marketed as "microbeads" or some such.
A paste of baking soda and water on cotton balls worked well for me, albeit tedious.
You fix it pretty easily by just getting the lenses entirely replaced. If you have vision insurance, you can do it entirely for free
Does someone willing to strip off the coating of their glasses sound to you like someone who has vision that allows for more than one pair of glasses a year?
How often do you replace your glasses? (Just curious, since you mentioned replacing yearly).
My last pair started peeling at 5 years, and I needed a new script by that point anyway.
Hi Costco glasses guy, I see you.