Can you cut tempered glass? I want to cut part of the bottom of a fish tank out. I called 2 different glass shops today, and the female that answered the phone at both places said "oh no, you can't cut tempered glass". My Dad says he's had it done...replaced the glass window in a wood burner. I'm going to check with a couple other glass places tomorrow...if it is possible, can I do it myself?

No, well you can try if you have a good flat bench and score the hell out of it. I put the odds at 4-1 you end up with a million little peices.

Wear eye protection! <img src="/forums/images/graemlins/cyclops.gif" alt="" />

Shouldn't it be cuttable with a diamond wheel or something?? I may just end up busting the whole bottom out of the tank...I could make that work too. <img src="/forums/images/graemlins/frown.gif" alt="" />

I would doubt that glass in a stove would be tempered.. reason.. constant exposure to high temperature would remove the temper..

From my materals engineering course from many decades ago... Tempered glass is made so by the cooling process as the glass cools from the red state..

The cooling process leaves the middle (...and the outer layers under compression.. This takes advantage of glass's inherent strengths and weakness.. i.e. glass is very strong under compression and weaker under tension (similar to concrete). As the link above indicates, there are other ways to temper glass..

So when a sideways force is applied to tempered glass, the outer layers are most affected and with little effect on the inner layer under tension. The sideways force merely reduces some of the force of compression in the glass on the side opposite to the force and adds compressive force on the side of the force. This little trick is what gives more overall strength.

When it finally cracks, the now unbalanced compressive and tensile forces inside the glass is the energy source that causes it to shatter into many pieces..

Trying to cut it would release these same internal forces... If you can successfully cut it, doubt it has very much temper..

Don't know but, aquarium glass instead of being tempered, may be high plasticity glass e.g. flexy glass, another characteristic to resist breaking.. Plasticity and temper are generally mutually exclusive.. optimizing one reduces the other..

Heck with it...I'm gonna bust the bottom out and make another bottom that meets my needs. My Dad must have been confused about the type of glass he was dealing with.

I googled "cutting tempered glass". From everything I read, Dandeman is right on. You aren't going to cut tempered glass, at least with anything you will have at home.

Laser and water jets are the ways I've heard of before.

Cutting wheel on a dremel tool...actually, about 30 cutting wheels <img src="/forums/images/graemlins/smile.gif" alt="" /> Took forever, but cut it without cracking.