Lens polishing - is it possible at home?

[pasiasty]

I wonder if it's possible to re-polish lens at home. Surface of some of my old ones is not as clean and glossy as it was (or rather as I suppose it was). Scratches, if there are any, would of course remain.

[Steven Tribe]

The only way to polish optical surfaces is to have (or make) a polishing surface which exactly matches the lens surface. Most lens manufacturers have not retained their old tools for polishing the various lenses they made. In theory, if you know the exact radius of the surface, then you can make a new tool. Both the production of polishing tools and the skills needed are not easy.

There may be new technology available in the lens industry, but it is not available to the likes of you and me.

Anyone who says they can polish lenses, without special tools, is charlatan.

[Vick Ko]

I disagree. There is a whole hobby of making telescope lenses, at home.
It is not easy, but, it is also not rocket science.
Start by researching how to polish telescope lenses, and how to make a pitch lap.
Then find companies that sell the polishing materials, and even the machinery to mount and polish lenses.
You will discover that while it is not easy, it is also not impossible.

Best of luck

[polyglot]

Yep, the telescope people are well into this and you can easily buy all the supplies (grinding paste, cerium oxide, etc) online because of all the nutters who build their own telescopes from scratch. There are techniques to get the polish within a fraction of a wavelength with some care.

It's a huge amount of work (especially by hand) and doesn't work with aspherical elements, but spherical element polishing is possible because you can make a mating surface by pouring pitch on your lens.

[Nathan Potter]

As Vick Ko and Polyglot said use a mating surface derived from the surface of the lens to be repolished. The difficult part is to keep the glass to mold surface free of particulate contamination during the polishing in order to avoid scratches. And as Steven implied - this is tricky business.

Nate Potter, Austin TX.

[Sevo]

Anyone who says they can polish lenses, without special tools, is charlatan.

Making lenses from scratch is more difficult (the issues of creating a template and keeping both sides perfectly centred are hard to solve with DIY means). Re-polishing is relatively easy, as you already have the lens as a template.

The special tools would be a couple of plastics cups, ultra fine grained plaster or (dentists) casting/forming compounds, and polishing grit in a variety of very fine to ultra fine grades. Beyond that, it is merely a matter of patience, discipline and meticulous cleanliness...

[Steven Tribe]

Of course you can use the existing surface as a template. But you will certainly need to practice on a few unloved lenses first. When the polishing form is just the same size as the lens, there is considerable difficulty is taking the same amount of glass off at the centre and the edges. There is a time honoured method of (almost) ensuring that things work out as they should.

"Anyone who says they can polish lenses, without special tools, is charlatan."

Making a pitch, or other cast, polishing surface is, in my view, a "special tool".

[Curt]

I have a pair of polycarbonate lenses in my safety glasses. Somewhere along the way I got a wide whisp of scratch on one. Figuring they're done for I buffed out the scratches on my stationary buffer. It buffed the scratch right out and off.

[AtlantaTerry]

I have a pair of polycarbonate lenses in my safety glasses. Somewhere along the way I got a wide whisp of scratch on one. Figuring they're done for I buffed out the scratches on my stationary buffer. It buffed the scratch right out and off.

1. most likely your safety glasses had flat lenses.
B. you are not taking pictures through the area you buffed.

[Jim C.]

Plastic is a different material than glass, it's pretty easy to buff out plastic, but a glass lens element is different .