How do you know if glass is tempered?

[kuatto]

I've got 4 or 5 glass doors(i think they're off things like china cabinets,ets,found when I was cleaning out my garage)1/4 inch 4'x2' pieces.Doesn't have any stamp/markings,so how can you tell?

Jim

[Canadian Man]

If you have a pair of polarized glasses put them on and look at the glass. If you see waves in the glass then it IS Tempered. No waves, No tempered.

cheers

[kuatto]

the only glasses I have are for my laser level,they're deep red to protect against the laser.I guess I'll just try cutting a broken piece.

Jim

[Delphinus]

If you have a broken piece of it, my guess is it's not tempered ... shouldn't it have shattered instead of broken?

[Kayleb]

Originally Posted by kuatto

the only glasses I have are for my laser level,they're deep red to protect against the laser.I guess I'll just try cutting a broken piece.

Jim

If there is a broken piece it can't be tempered, because when temp glass breaks the entire piece shatters into 1000's of small pieces. And the same happens when you try to cut it. I had a large piece of temp glass from an
old sliding glass door, seemed a waste to toss it so I tryed to cut it, one thing good is it went into the garbage pail a little easier after I swept up
all the pieces.

[kuatto]

As soon as i find my glass cutter,i'll start cutting.Are there any tricks to make the cutting go smoother?If it all goes to @#$! then no worries because the glass was all free