Anneal - cut - retemper

I got an e-mail asking where one might get some tempered glass cut. The pieces in question are 3 meters by 2 meters by 1 and 1.2 cm thick.

I suggested that it may well be cheaper to simply have the new pieces manufactured from scratch, but the querant wishes to shop around... so the question is, Does anyone know of a place that could anneal some glass that size, cut it, and retemper it?

TIA

down the street, third door to the left.

you don't say where in the world you are. it would be cost prohibitive to ship these around the world to do.

Those are pretty big sheets of glass, which means that it will likely shorten the list of folks that can do it quite a bit - probably to one of the big manufacturers...which will make it pretty pricy as they don't really do that sort of thing. I would recommend first off that they redesign the project to use the glass as is. If that is not possible, I think your recommendation, of simply buying new panes is best. I can't say that I have really ever heard of folks re-tempering glass of any size. I fear that the process just won't work that well. Perhaps he can sell them on Ebay as solar collector panel covers, and, make back some of the cost. Regards Dave Mundt

Not cost effective to walk across the room with it!

Cost of Double strength, when buying truckload quantities, is around 50 cents a foot, takes 6 minutes to run thru a tempering oven to temper, that is up to 1500 and back down to room temp, to put stress INTO the glass.

But I have never heard of taking tempered back to annealed then cut and re-temper. I would think the stress in the glass would cause it to break upon re-heating.

Wish the person luck in their search.

heat won't set off tempered glass. one just needs to raise the temp over the annealing point and reanneal. of course, since this is float from an undetermined source, what that point is is also subject to a guess.

Having formerly worked in a glass tempering plant, the short answer is can't be done cheaply and most companies with an oven won't even attempt it. Toss out the old and order up the new.....

It would be cheaper to have tempered glass ordered to spec rather than ship it back and forth. Also, none of the annealing places I know of will guarantee YOUR glass that you send them will make it through the oven. But if you order glass with holes or notches or whatever, they will make it and ship it to you. If some break in the oven while they are making it, it's their problem not yours.

Neither does the person in question, really. His English is really poor, he gives a return address of Thailand, but e-mails from a uk IP address. I don't know if the glass is in Thailand, the UK, or some other place.

I figured I'd throw the question out, and then simply point him to the thread in Google. :-)