Learn how to make fun optics:

Lenses are fascinating both the process of making and the wild distorsions they create are a great skill to learn.

Glasses, telescopes, microscopes, kaleidoscopes... are all lenses.

With these steps you will learn tricks on how to make concave lenses in a cold working glass shop.

Step 1: CHECK YOUR GLASS

Make sure there aren't any cracks in your glass piece. If you have a polarized lens you can use it to check on cracks. Otherwise simply looking at every surface before starting works too.

Step 2: MARKING

Use a sharpie marker to trace the location where you'd like your lenses to be. It's always best to draw a circle slightly smaller inside to avoid carving the outside cercle.

In order to stay perfectly circle use a sharpie to mark the cercle. The water and friction will take the sharpie off after a while so it's absolutely normal if you spend more time marking then carving at first.
After lots of practice your eye will get more and more trained and you will be able to carve a circle without using as many marks.

Step 3: GRINDING

In a coldworking glass studio you will be able to grind your sheet of glass.

Clothing: Wear a mask, apron, and plastic boots because the silica+ water will get all over as your grinding the glass.

Place the water in order for it to drip on the glass to avoid thermal shock.

Since the grinding wheel has a rounded profile it will carve the glass with a round outer shape. It takes a lot of time and practice to do a perfect cercle. Marking the glass with some extra space will be important incase the outside of the cercle gets scratched.

Movement: When you are pushing the glass onto the wheel make sure you are not pushing too hard since the wheel does the job simply bringing it gently close to the wheel with a firm grip will suffice. Sometimes you can do very minimal horizontal and vertical movements but the more you are still the more the round will be carved evenly without any bumps.

Step 4: TRANSLUCENT TO TRANSPARENT

As you can see on the attached picture the area that has been carved is cloudy and the untouched area is transparent. Here is the key to a perfect transparent lens with no translucent " cloud" and no scratches:

Similar to wood and metal glass can overheat. Make sure you are cooling the glass with the water drip and not staying on the wheel too long. It's always good to take breaks and feel the glass incase it got too warm.

Start with the roughest diamond grit wheel to the finest one to get a perfect glass shine.

Order of carving lenses with a spherical diamond grit wheel:

80- 150- 180- 320- 600 - felt wheel

Once you are satisfied with the look of your lens and the finish it has. You can go to the felt wheel shining area to improve the shine.

Use a mix of pumice and water added to the felt wheel to create a fabulous shine.

VOILA