Grinding Glass Optics with simple tools?

At some point I need to grind the lips off a 42 mm aspheric lens from KD.

I know it can be done using simple tools as others have done it but I don't know how or what the various ways are.

I don't have a dremel but do have a few tools. I have a random orbiter sander and can buy other more basic tools if necessary.

I only need to grind one or two lenses and it doesn't have to be a perfect job.

Any advice?

The lenses aren't here yet so I'm can't experiment and thought I might as well get the advice of others.

I thought maybe just turning on the random orbiter sander and holding it in one hand and holding the lip of the lens against the sandpaper and rotating it every now and then might work.

Other than that I've got no ideas at the moment.

The random orbital sander will work but will be very slow. I would seriously consider purchasing a dremel or, even better, a bench grinder. While a quality tool would be a better purchase, even a Harbor Freight tool will be ok for this job.

Try hard to not breath the dust from grinding glass. It is really bad for you.

HarryN said:

Try hard to not breath the dust from grinding glass. It is really bad for you.

Click to expand...

+1 Silicosis is something to avoid, like the Jets flying over Icelandic volcanos!

The proper way to do it is ask the help of your cities Vitro/stained glass workshops...tehy have a special glass grinder for thsi job....

It is actually a glass eating roller and the glass is put perpendicular to it on a flat mesh surface.....water is used and that makes the grinding easier and safer....guess you can make something like this with a dremel and a vice....

What ever you do do not put a file perpendicular to the glass surface...thsi chips the glass...Don't ask me how I know

I've done a few. I use a bench grinder that has two wheels one is more course and the other finer. Use the finer wheel. Take the grinder outside, next put on safety glasses and a mask for your face if you have one. Turn the motor of the grinder on and while wearing thick gloves hold the lens flatside down and place your thumb in the center and use your other hand to constantly rotate the lense in a circular direction. As you make a few passes keep taking the lens off the grinder and checking it to make sure you don't take too much off. when your all done take a brush and wipe down your grinder.

I don't have a bench grinder nor do I have access to one. I could buy one I guess but the only need I have for one is just to grind down these two lenses.

Initially, I was just wondering if there was an even low tech way to do this.

You might find some info if you look up amateur telescope making.

Try a local glass shop i have found them very accommodating for small special interest jobs ..

You can do this with diamond files by hand. It's not too slow...

A Dremel tool (or any equivalent) with a diamond bit will work quickly as well.

If you want to go caveman style, I did do a lens by just dragging it across concrete. It works and takes the lip off the aspheric, but be careful, one slip and it will scratch up the lens pretty easily..The bench grinder is definitley the best method though.

+1 vote for the bench grinder.

I've done it with a really weak $30 grinder. The thing is pretty sad, you can easily stop it when grinding metal, but for lenses it's fine.

So you may choose to buy a little bench grinder. It's a very useful tool to have, especially if you buy a polishing wheel or two.