You know how car windows don't shatter like normal glass windows? When they get smashed, they sag like fabric. What kind of sorcery is this? It's safety glass, and it's AWESOME!
Safety glass is made by laminating two pieces of glass together with a sheet of plastic in the middle. You heat up this little sandwich and press everything together, and the plastic melts and sticks to the glass. Once everything cools down, it looks just like a normal piece of glass, but if you smash it, the plastic holds everything together. The glass is now a composite, and it's notably stiffer than a single sheet.
As it turns out, it's really easy to make this yourself using just a bit of plastic, binder clips and a toaster oven. And once you can laminate glass, life just gets better and better.
Step 1: What You Need
I'm just experimenting with this stuff, so I'm using itty bitty pieces of material. The same process works for larger pieces of glass, though.
glass microscope slides -- $.05 each from your local science depot. Tonight, I learned that, in Manila, you can buy microscope slides at the drug store. Isn't that awesome?
EVA film -- This is a thermoplastic film that will hold your glass together. You can get it pretty cheap on ebay. Get yourself a nice bialy roll of the stuff, because you're gonna want to play with this a lot.
Binder clips -- available wherever paper is looseleaf
A cheapo toaster. When playing with chemicals, I like to use dedicated equipment so I don't accidentally eat my experiments. Heated plastics play with our bodies in all kinds of ways that we don't understand. For $10, I can get an extra toaster and avoid being an inadvertent guinea pig. Plus--science toaster!
Step 2: What You're Going to Do
Here's a sped-up video showing the process. It really just takes a minute to make a piece of safety glass.
The music from this video is by the band Beirut. Beirut made this great full-length film of themselves playing their music, called Cheap Magic Inside. Did you know that? Every time I see them singing Nantes in that staircase in brooklyn, I tear up. You should totally watch it!
Well, ready to make some glass? Spin up a Beirut album and let's go!
Step 3: Sudo Make Me a Sandwich
Well, make your sandwich and clip it up. Not much to show here--just cut out a piece of EVA and slip that between the buns. Clip it together like crazy with binder clips--pressure makes the difference between a beautiful piece of safety glass and a beautiful piece of ugly poop.
Step 4: Old Gold: It's Toasted
Now throw that sucker in the oven. EVA melts at 80 degrees C, and your oven will get a lot hotter than that. You can tell when it melts, because it turns perfectly transparent. EVA is index-matched to glass, which means that when the plastic is pushed right up against the glass, light will pass through both of them as if they were one material. As soon as the EVA turns transparent, turn off the toaster and carefully pull out your sandwich. Let it cool down, and then pop the clips off.
This photo is from an early experiment and I don't have binder clips on my sandwich. You should--everything, binder clips and all, goes into the toaster.
Step 5: Give 'er a Whack
Well, you're done. I know--super easy, right? If everything went right, your glass should be crystal clear. Give it a whack with a hammer and be astounded that it doesn't shatter like normal glass. Now go hug a sad banker.
Step 6: An Exercise for the Reader
I started playing around with glass lamination because it's the method people use to make solar panels that last twenty-five years outdoors, and my friend Shawn and I are on a mission to make the best small-scale solar panels the world has ever seen. If you make your own solar panels from scratch (here are somelovelyinstructables we wrote to show you how to do that), you can encapsulate your panels in glass and EVA to make waterproof, long-lived panels. Here's an image of the first test panel I made using this method.
You can also put other stuff into the glass. I played around with laminated leaves and flowers from my garden in between a couple pieces of EVA inside the glass. I'm particularly pleased with how my canteloupe flower turned out. Wouldn't it be cool if your car windshield had flowers built into it? Play around with it! Shove all kinds of stuff into the glass. Adhere glass and EVA to the front of a surface-mount circuit board to make lovely, glass-fronted PCBs that everyone will love. Stick glass slides to your walls. Stack two glass panes and some spacers together to make your own double-glazed windows. Go nuts!
Well, that's what I've got for now. Go forth and DO stuff!