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Make Your Own Safety Glass and Other SHENANIGANS

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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.  

Ready?  Go!




 
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Step 1: What you need

Picture of What you need
binder-clip-daschund.jpg
7101-BU_-_Microscope_Slides.jpg
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.

I used:
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!

Treknology2 years ago
In Australia, "safety glass" means the stuff that shatters into thousands of little bits, so that there are no large shards that could penetrate the body.

Your example is called "laminated" and is usually only available for windshields. When my car's back window shattered, I made sure the replacement had tint film right to the edges before being fitted back into the rubber seal. If it shatters again, it will be held in place by the tint film.

Ironwolfcanada mentions that "safety glasses" are not made from glass. They are usually made from polycarbonate, which means they don't like exposure to oils.

Have you experimented with various colors introduced into the plastic layer?
Mate I make safety glass for a living in Australia and the majority of safety glass in windows is laminated with pvb not just car wind shields. The glass that shatters into tiny pieces is furnaced glass aka toughened. We laminate that too. There is regulations on what type of glass that is glazed into building. High rise buildings should be 13.52mm laminated toughened. Normal houses regulate that windows have to be 4 mm float and thicker.
Gilo Treknology2 years ago
Safety glass is made for glass. The plastic that sandwiched in between the two planes of glass is polycarbonate plastic.
prank (author)  Treknology2 years ago
From my wikipedia search, both of the types of glass you mention are solutions to the same problem of keeping glass from becoming millions of tiny knives when it breaks. The glass that shatters into thousands of tiny bits is tempered glass, and it's the strongest glass available (according to wikipedia).

The laminated stuff I make in this instructable is actually pretty common in architecture. If you run your finger along the edges of cheap, fancy glass walls, you'll feel something rubbery -- that's the edge of the EVA or TVB film in between two laminated pieces of glass.

I saw somewhere that you can also laminate polycarb to glass, which sounds pretty frickin cool. I really like the idea of laminating multiple colors together--I'll have to go dig up some polycarb and give it a try
I think the stuff that shatters into little bits is tempered. I think that kind is best for cars, because once broken, it has no leverage to slice someone open. The laminated stuff seems like a good option for tall buildings so people can't fall out of a broken window.

Prank, have you experimented with multiple layers of glass to stop projectiles?
I like this idea very much, but when I searched eBay, I couldn't find the thermal plastic product under the name you supplied. Can you give more information please?
Many thanks for that Prank, the concept and discriptions you have given can help anyone who wants to do this project for making their own laminate.
Noel
prank (author)  Noel Pulleine2 years ago
Hmmm. Did you check the link from the materials page? It goes to an ebay vendor that's selling EVA film, and this ebay search for EVA film turned up a bunch of results--http://www.ebay.com/sch/i.html?_trksid=p5197.m570.l1313&_nkw=EVA+film&_sacat=0

Here is a link to EVA Plastic Films
http://www.blueridgefilms.com/eva_film.html

And here is another link to all kinds of links to Eva films
http://isearch.avg.com/search?cid={3F5688F2-A5DC-4CFB-8282-3678D765DDA5}&mid=6826f94916fccf73643815153ead7b87-9557abddcd2a82ce3aec9d57c4d569e029d61ac8&ds=AVG&lang=en&v=11.1.0.12&pr=pr&d=2012-03-29%2016:55:24&sap=dsp&q=eva+film+properties

Hope this will end the controversy here.;>}}
This would be great for picture frames!
also have you noticed how well insolated the car is with windows all over it? i think larger glass panes might be a cheap alternitive to the sweet double pane windows. plus when i toss a bat through them again it wont make such a mess.

yes when i was in high school i accidently threw a bat through my grandmothers back window. double pane and 9 billion shards of glass later the bill was close to 600 bucks. and that was in the 90s.
Not sure where you live but respectfully you seem to never spent much time in a car or in a home with single pane glazing in cold weather. Glass is great conductor of heat, not an insulator.
ask4122 years ago
I have worked with laminated glass, can size cut and finish it.

This is a great kids science experiment. Interesting, but not suitable for real glazing.

Anyone wanting "laminated glass" cannot go wrong just going to a glazier. It is relatively cheap to have glass cut to size, choosing strength and thickness of quality laminated glass, for automotive use or domestic.

The glass 'experiment' is most definitely not 'safety glass' as that is toughened glass. Toughened glass is either heat strengthened or fully tempered glass.
http://www.youtube.com/watch?v=uA7RTxX2KL0

Laminated manufacturing of glass is done with annealed glass.
http://youtu.be/VTKLjtcbnn4

For some laminated windscreens fitted in certain European model vehicles glass is heat strengthened and zone toughened laminated glass. Both glass processes used for occupant safety.
jspence12 years ago
Interesting idea - thank you.
The EVA film is expensive! I wonder if you could use 'low E' film instead.
Neat idea, and has numerous applications,
BUT, not for "safety glasses"!!!
When safety glass breaks, tiny shards of glass DO separate from the plastic
core, and if you were wearing "safety glasses" made with glass,
it's highly probable that these shards of glass would get in your eyes.
This is why 'safety glasses' are NOT made from glass!
Keep up the neat ideas!
agis682 years ago
excellent instructable......
rimar20002 years ago
Very good idea!

I like the "captions" on the video, because I can read English but I don't understand it when spoken. Thanks for that.