How Much do You Know About Your Glass?

Glass today is pretty ubiquitous, to the extent that most of time we just look right though it without any thought. Yeah, that’s glass’s job, I get it, but it was a figure of speech. Anyway, there’s so much of it around us, and it facilitates so many things in our everyday lives, but how many of us have a clear idea of what it really is, how it’s made and where it came from?

So what is it, really? What’s in it? Typically, most basic glasses comprise various percentages of three crucial components: sand, potassium carbonate, and chalk or lime. What percentage those things come in really depends on what the glass is being used for, but, generally, it’s about 75% potassium carbonate, 24% sand, and 2% lime. Coincidentally, potassium carbonate is also used sometimes in soap, cocoa powder production, and as an ingredient in those delicious Chinese mooncakes with the fancy designs on them. Here’s the Wikipedia link, in case you need a rabbit to chase.

Most people would probably have guessed that, to actually make the glass, these three elements would be melted down into a molten-like form. And that’s exactly right. It can be heated any number of ways, so long as it reaches about 1000°-1600° Celsius. That’s hot. For those of you still clinging to standard measure like it really works (don’t worry, so am I), that’s upwards of 3000° Fahrenheit. Again, hot.

Once its molten, there are various ways to remove any impurities, including chemical additives and agitation. I’ll tell you, though, agitating a vat of viscous, sticky, 3000° incandescent sauce seems like a bogus plan to me.

With impurities gone, the burning goo can be drawn and rolled into giant sheets, for flat glass. Or, it can be pressed and blown, for hollow glass like light bulbs, fixtures, and fishbowls. Colored glass can be dies while in its molten stage, and it can also be printed or coated to achieve various colors. Mirrored glass is usually coated with a metallic, paint-like substance—mostly silver.

Considering the temperature at which this stuff is made, how long do you think it has to be cooled? Good question. It depends. The cooling time effects the final product’s brittleness and strength, but, generally, the slower the better. The strongest annealed glasses—those that aren’t subjected to further heat strengthening—can take up to several months before moving to other phases of production. I’m glad my pizza doesn’t take that long, because most of the time I barely have enough patience to wait for the cheese to cool. Man, I hate cheese blisters.

So how long has this whole process gone down? Well, a while. The approximate recipe we mentioned was probably drawn up by the Assyrians some time around 640 BCE, but we think glass has been produced as early as 8000 BCE, especially in Egypt, but maybe in Mesopotamia and Mycenae, China, and Northern Tyrol—a tiny little region of northern Italy and southern Austria.

Glass is obviously a lot different, and a lot more widespread today. But even as recently as the early Industrial Revolution glass was something of luxury. For example, you may have heard that in the late-17th century, the UK parliament imposed a window tax on its citizens across Scotland and England. Since glass was so expensive, having a lot of glazed windows was seen as an indication of prosperity, and thus the government felt added revenue could be extracted simply by adjusting taxes based on the number of windows a household enjoyed. The tax lasted until 1851—well into the Industrial Revolution—when it was repealed, as prosperity was no longer seen as a legitimate basis for increased taxation.

Now glass is everywhere. It’s easy and cheap to get, and we’re even coming up with new concoctions, like Gorilla Glass, by Corning, which uses alkali-aluminosilicate sheet glass stretched and flattened to be incredibly thin and almost unbreakable—almost. My old Galaxy 7, using the fourth generation of Gorilla Glass, didn’t quite make a shoulder-height tumble. Think we’ll have Gorilla Glass in our cars some day? Porsche does.

See you later.

A Look Back Through Our Window of History












What’s Up With That Crazy Windshield?

Your windshield—it’s the thing you take for granted, probably almost every day. You might check your oil, or your antifreeze, or your tire pressure before you head out for a trip, but how many of us even think about our windshields, aside from cleaning off the bug goo? Well, the team at Block & Olson thinks it’s time you give your windshield the credit that it deserves. So here’s some cool knowledge about that stuff in front of your face when you’re driving, the stuff specifically designed for you to overlook.

Your Airbag Needs It

When most of us consider the safety benefits of our windshields, we think about it keeping rocks and bugs and weather from smacking us in the noggin while we drive. Sure, it does that, but it’s also an integral part of most modern automobiles’ crash safety systems. Passenger airbags, for example, often use the windshield as a sort of launching pad when inflating. Think of the little starting blocks Olympic runners push off of to start their races. Without the windshield behind it, the airbag ignition canister might not have as much leverage, and the bag might not inflate properly. Other systems use the windshield as a backboard to rebound the airbag toward the passenger. Passenger airbags often release from the dashboard. Consequently, they inflate upward, and let the windshield bounce them horizontally toward the rider. So it’s likely that your airbag depends pretty heavily on the windshield being properly installed and of reliable quality. That’s why you want experienced techs working on your car, installing the best stuff there is.

If It’s Cracked or Chipped, It Won’t Just Cave in or Shatter

We’ve been in the game a long time, and a lot of people seem to worry about the cracks in their windshields making the glass collapse while they’re driving, or rocks blasting through their windshields into their seats. Now, in particularly gnarly situations, those things aren’t out of the realm of possibility, but we’ve been in business for almost 70 years and we can tell you, it’s extremely rare. We once put a windshield in a car that was sat on by a horse. The window was broken pretty badly, but it was not even close to caving in. The fact is, windshields are incredibly strong. Modern windshields are made of 2 layers of heat strengthened glass, sandwiched together with a sheet of extremely tough vinyl. Rarely do rocks make it through the first layer of glass, and almost never into the vinyl. Heck, we have a hard time breaking them to fit in our dumpster. Now none of this should be taken as an excuse to drive around with that crummy, busted windshield in your car. It obstructs your vision, and you can definitely be ticketed for it. So get it fixed, but don’t worry about it flopping on your lap on the freeway in the meantime.

It’s Good For Your Skin

What? How in the heck-sticks is a windshield good for your skin? We’ll tell you. Not only the glass, but the vinyl in between it, these days, is treated with UV protectant. Some of us spend hours and hours in our cars every day, and imagine if the sun was baking malevolently through the glass and blistering your skin the whole time. No thanks. Imagine how much sunscreen you’d go through in the summer. But no! The glass in your car helps keep that nasty, burning jerk from boiling our epidermises—or maybe it’s epidermi. Anyway, want to check our facts (friends who wear transitions glasses will know what we’re talking about)? Find a friend who wears prescription glasses that turn to sunglasses outside. Take them for a ride in your car and watch their glasses. The don’t change! That’s because the material in the prescription glasses uses UV rays to darken. Thanks to your car windows, there’s no—or at least very, very few—UV rays bouncing around in your car. Amazing!

It Might Be Why Your Insurance Costs So Much

Windshield repair and replacement are by far the most frequent insurance claims for auto insurers. At Block & Olson, we replace and repair a ton of car windows every year, and almost all of them are insurance jobs. Rock chip repairs are so commonly reported that most insurance brokers don’t charge at all for the claims. That means you can usually get your rock chips repaired for free. For replacements, you’ll have to foot the deductible, but in many cases, that deductible is less than your collision or comprehensive deductible. If you have a claim or any questions about one, get your insurance folks on the phone and they’ll help you out—or call us up, we’re pretty savvy too. If you do call your insurance company, tell them Block & Olson is your shop! (Hey, it’s our blog, don’t you expect us to self-promote sometimes?)

The Weirdest Fact of All

In many states, you’re not required by law to have a windshield. Yup. It’s a throwback to the days when auto windshields were a luxury, when only the rich could afford cars and only the richest of them could spring for glass to keep the wind from their faces. Now before you go taking the glass out of your car and blasting around the town, you should check your state and local laws, because we’re not lawyers or legislators or cops. But a lot of our classic car clients drive their old hot rods in for custom glass without the windshields. Still, they are required to wear safety goggles. So goggle up! And here’s the weirdest caveat of the weirdest fact today: whether or not you have a windshield, if your car came with them from the factory, you are required by law to have windshield wipers. What?! Yes, even if you don’t have a windshield in your car, you’ve got to have those wipers. Wacky.

So next time you make the rounds about your car, checking the oil and kicking the tires, remember that humble windshield sitting there unnoticed, and probably gooped up with bugs. Remember all the amazing things it does for you while you stare through it every day. Poor, poor neglected windshield, we love you.