Repair: Polishing Glass part 1

Hello, everybody! I’ll be showing you today a simple procedure that I do for polishing glass. This is the safest way that I know of, the other procedure that I rarely do is more aggressive and may change the curvature of the glass. This is not something that a beginner should attempt, this article is merely for your education and entertainment.

Since I am known for buying lenses that are in poor state to dismantle and document for this blog I regularly encounter lenses with damaged glass, some of them could be corrected to some extent while some of them are beyond restoration. For cases where there’s still hope, I’ll try and polish the affected parts.

This thing has seen better times. The fungus has etched the glass and left the acid scars from the mycelium. It is common for me to encounter this but this is not something that I should worry about.

This method requires cigarette ash. If you smoke, collect the ash inside a film canister. If you don’t then ask a chain-smoker friend to do this for you. Filling a canister takes around 2 boxes of cigarettes at least.

I learned about this method several years ago, from Zeiss no less. It was mentioned that cigarette ash is best as it has a triangular structure. I’m not a scientist so I’ll just take their word for that.

Not all cigarette ash will be suitable for this, you should use the ones that are fine. No seeds, rolling paper and traces of other stuff should be in the ash. Avoid using the ash of fancy, flavored cigarettes. Menthol is fine but it’s best to just use the ones from a regular. I am not going to mention any brands because I am not sponsored.

Sprinkle a couple over the affected surface, be sure that it’s dry as you don’t want to make a slurry. Rub it with a clean cloth, it should be made of pure cotton. An old T-shirt is best, I personally use my old briefs. Rub it and check the results every few minutes. It usually takes me around less than 10 minutes of rubbing to get a nice result. Do not rub too hard, do it with even pressure and in a circular manner. Add more ash when needed.

Most of the scar is gone. You couldn’t remove everything with this method but it’s still better than nothing.

This is a more serious case. It looks like the coatings will be mostly gone after the process. It couldn’t be helped and it’s better than leaving it that way.

After the procedure there’s still traces of the damage left. It looks better than how it looked originally but I am sure that the coatings here have been stripped. Fungus will deteriorate the hardest coating so it disintegrates easily when wiped.

Getting rid of the cigarette smell is not difficult. Use water and a few drops of soap, rub the surfaces with your fingers and clean everything with clean water. A final rinse is essential and distilled water is what you should use to prevent leaving any mineral deposits. Wipe the glass with alcohol and naphtha as finishing touches.

Despite being mostly benign this will still alter the glass. Only people who know what they’re doing should do it. You should also remember that not every surface uses baked coatings. This will strip any soft coating away like the ones used by the Germans and Minolta. Nikon’s later coatings are soft, too. In my experience, this way is best-suited for earlier Nikkors because the coatings are tough. It’s fine for uncoated surfaces but I wouldn’t do this if I could avoid it. That’s all for today. Remember that smoking is bad for your health. Just count how much money you spend on them, you’ll be surprised that you could’ve bought the Nikkor Z 50mm f/1.2 S with it. As a last warning, this article is only for your education and entertainment.

Thanks for following my work, if you liked this article please share this with your friends so it will get more views. This site earns around $1.10 a day, it’s totally reliant on views. You can also support this site, it helps me offset the cost of maintenance and hosting. You are also helping me purchase, process and scan film. This site promotes the use of film so we’re all in this together. See you again in the next article, Ric.

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Helping support this site will ensure that this will be kept going as long as I have the time and energy for this. I would appreciate it if you just leave out your name or details like your country’s name or other information so that the donations will totally be anonymous. This is a labor of love and I intend to keep it that way for as long as I can. Ric.

2 Comments (+add yours?)

  1. Matt
    Dec 13, 2020 @ 07:02:01

    Thanks Ric, this is a Kool way of polishing a lens.
    By the way, did you know there is a brand of cigarettes in Germany called ‘F6’?


  2. Tibo Alberny
    Dec 13, 2020 @ 21:17:07

    I have to give it a shot tomorrow 🙂


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