If you think about it, you'll agree that ordinary house glass is pretty amazing. It's strong, clear, and really quite affordable. Its only real drawback is that it is brittle so when it breaks it can create dangerous shards, making it a poor choice for automobile glass.

Plastic is safer, but it isn't scratch resistant so it doesn't remain clear enough for automobile glass. Auto manufacturers? use tempered glass on the side windows which is much stronger than house glass and when it does break, it breaks into tiny little cubes that aren't as dangerous as shards. They can still be sharp but they are far safer.

But tempered glass doesn't work for windshields. Because the windshield is constantly being hit with tiny pebbles, sand, gravel, and other road debris, tempered glass would have a very short life span. So manufacturers started using laminated glass years ago.

Laminated glass is simply two thin sheets of tempered glass that are fused to a rubber inner layer. The two sheets are independent. What the rubber layer does is act like a sponge, absorbing the shock and reducing the chance of breakage from small particles like pebbles.

If a rock hits the window hard enough you'll land up with a stone chip, but it usually only breaks the outer layer of glass. If something really big hits the window and shatters both layers, the rubber membrane will stop the windshield from falling in your lap. Windshield repair works for the rock chips that have damaged the outer layer of the glass.

Start by buying a windshield crack repair kit at Wal-Mart, Sears, Canadian Tire, Lordco or other department or auto stores. Once you've got your kit, dry the windshield to room temperature. Don't bother trying to do the repair on a wet day unless you can park inside.

Use a hair dryer to dry the window. This will pull the moisture out of the window so that the repair works. If the windshield is dirty, clean it using a harsh cleaner such as lighter fluid. This will remove any grime or film.

The repair process is very straightforward. Peel the back of the adhesive strip and apply it to the pre-cleaned glass. Center it over the chip, then burnish with a blunt object. Peel away the remaining film. Line up the adapter so it's as vertical as possible, and then stick it to the film. Again, burnish with a blunt object.

Take the cap off the syringe and attach it to the adapter. Pull the syringe out as far as it goes. Hold this position for one minute to create a vacuum. While you are holding the vacuum the air in the crack begins to bubble up in the syringe while at the same time the adhesive seeps deep into the glass and chip.

That's it. Your chip is repaired. The adhesive is a type of resin that bonds with the chip and creates a seal, and thus a repair. You can also use the windshield repair kit on cracks. Once you've correctly done the repair, the glass will no longer spider and the damage won't spread.