# Accident with glass coffeepot



## margsu (May 9, 2010)

Today I had quite interestind accident. I dryed my AR in glass coffepot whet it crashed. I am OK without any burn, but my AR is gone. But if I use steelpan for drying. AR solution is not corrosive when I dry it because I dissolve as much scrap as possible. If it's not reacting anymore then I dry it. I read from internet that one guy suggest steelpan for drying. Glass pot is not a good idea.


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## lazersteve (May 9, 2010)

Invest in a shallow ceramic style baking dish. You can heat the glass container in it and if you get a break in the glass or a boil over, the ceramic dish will catch it.

The ceramic dishes are still sensitive to thermal shock so heat and cool the dish slowly or add a layer of clean sand to the dish to normalize temperature changes.

Steve


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## skippy (May 9, 2010)

The best would be the old style corningware - it's really resistant to thermal shock. I believe the new stuff isn't as good though.


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## goldsilverpro (May 9, 2010)

> The best would be the old style corningware - it's really resistant to thermal shock. I believe the new stuff isn't as good though.


I agree. The best, are the old-style 5 quart, white, opaque, square, flat-bottomed Corning Ware dishes. The newer, round, amber colored, transparent CW dishes work fine but, the shape is much more awkward to use - they taper down to a small base. As far as thermal shock resistance, they seem to be about equal.

I have used a small propane torch in both types to dry gold, with no problems. In the original TV ads for the newer amber style, I'm thinking they melted a large amount of a low-melting point metal (Al?) in them with a torch.

On the old-style white ones, don't damage the glaze on the inside, whether physically or chemically. I have heated concentrated sulfuric acid it them and, after doing this repeatedly, it eventually attacked the glaze and exposed a little of the porous material underneath. Then, this porous material absorbed the liquid and the dish cracked later on when I was heating the dish dry. Heating other acids in it seemed to cause no problems. I have not (and, will not) heated strong alkalies, such as a sodium hydroxide solution, in them due to possible attack on the glass contained in the ceramic.
http://en.wikipedia.org/wiki/CorningWare


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## margsu (May 10, 2010)

Thanks for good advice. Today I try oldtype steel pot with ceramic surface. I know that this cheramic don't want to heating without liquid.


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## qst42know (May 10, 2010)

I think you will find your enamel layer on a steel pan is not as impervious as you might believe. :roll: 

Look for glass or ceramic cookware meant to go directly on the stove top.


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## margsu (May 15, 2010)

Hi again. My test was successful, but ceramic layer must be normal witout any hole. Copper nitrate and copper chloride was react with steel.


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## dtectr (Jun 10, 2010)

hey all - finally an issue i can chime in on! lol
my wife has always cooked on electric ranges, and INSISTED we buy clover-leaf looking copper wire units to put below all glassware on stove - corning & otherwise. check the scan - hope it works. they run about a buck for 2 at dollar stores.

with electric elements, the elements heat the glass directly, in the area it is in contact with with, so adjoining molecules, within the design of the element can be at extremes temp wise, a thermal shock thingy. glass is thermally transparent, which is why you don't have this problem with radiant cooktops (at least thats what we were taught to say when i sold them at sears!) since the heating element is BELOW the glass, not in contact with it.

on gas ranges, (or hot plates) the prob isn't the flames, its the metal burner pot holder thingies (sorry to keep using these trade-specific scientific expressions, makes me sound like a SNOB, i know!)  that CAN heat up and create hotspots. usually best to start temp low then gradually build up if need be to temper the project. 

remember, the glass lets heat pass through, more or less, so if sludge is a large WET mass, it will remain at 212 degrees until water is evaporated, then jump QUICKLY once its gone, up to its melting point. 

since corning ware, the good stuff is getting harder to find at garage sales. a buck is cheap insurance.

i think.

hope this helps.


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