Sciencemadness Discussion Board

Fuck "Pyrex"

Flip - 26-4-2009 at 20:14

This is ridiculous. Ridiculous! I have to vent on you guys.

So I set up a water bath in a "Pyrex" brand dish on a corning hotplate set to heat level 4. Inside the dish is a mason jar with EtOH i'm just doing a metal replacement reaction. Anyway I get the temperature of the bath up to about 70 C and not wanting the EtOH to boil out I dial down the heat. So i'm sitting around just relaxing and watching a movie, when..

BOOM!!!!!!!

The dish explodes!! It sends hot water and shards of glass flying three feet in every direction! One of which found it's way into my leg! Surprisingly, the mason jar and it's contents remained intact as the dish blew out from underneath it, leaving it sitting on the plate as if there had never even been a bath underneath it. All in all, I was pretty fortunate that the incident was not worse.

Now how can this company market a brand called pyrex and put a pyrex logo on the fucking thing if it can't even withstand slowly cooling from temperatures under 100 C without violently exploding!!





Sauron - 26-4-2009 at 20:27

There's a lot of phony "pyrex" around that is not borosilicate.

This is particularlytrue of household glassware.

Where did you buy this?

What were the markings?

I am sure it was not made by Corning.

chemrox - 26-4-2009 at 20:36

There are also mechanical stresses that can be caused by the heating element. This is one reason those little copper wire star shaped rings are sold.

Flip - 26-4-2009 at 20:41

Yeah, it was a baking dish from the local grocer. The word "Pyrex" in big letters embossed on the glass. If it had the company or location of manufacture that evidence is in shards right now.

What took me was just how violent the pop was. Here I am, unsuspecting, sitting not three feet away. Got my heart racing and a nice little band-aid on my leg. I've had glass crack, but i've never seen it explode!!!

Corning may not have manufactured this, but I still blame them for selling out their trademark. The appeal of the Pyrex brand is it's temperature resistance. Now that brand name appears to have been prostituted to cheap imitations. Damn them!

Magpie - 26-4-2009 at 21:02

My wife placed a hot Pyrex brand clear glass cooking dish in the sink and poured cold water on it. It exploded into hundreds of pieces.

I think Pyrex brand lab glassware is still borosilicate glass and can take some thermal shock. My understanding is that the Pyrex brand cookware, however, is no longer made of borosilicate.

I think this is deceptive and dangerous use of the Pyrex brand, as anyone with lab experience is likely to be misled by it's use on cookware.

User - 27-4-2009 at 04:06

Well I've been after pyrex glass for a while.
The funny thing is that not all pyrex stuff is made out of borosilicate.
I found some old pyrex glass at a second-hand store and it said it was made out of borosi.
It is "very" resistant to thermal shock.

Lately I've been reading about glassblowing and stuff...
When the glass doesn't not harden out evenly there will be mechanical stress points.
Which will be exposed during hars condition.
Although these conditions you describe aren't to be called that way
It could be that this was just a manufacturing error.


Still, exploding is just f*cking ridiculous.
If i was American I'd say sue those bastards :P

not_important - 27-4-2009 at 04:14

Pyrex is a trade name, not a type of glass. Labware was labeled Pyrex borosilicate, as was the early Pyrex cookware. At some point in the past Pyrex cooking ware stopped being borosilicate in all cases.

You're not alone with your problem. There's a defensive page on the Pyrex site:

http://www.pyrexware.com/thetruthaboutpyrex/index.htm

and a consumer protection site has a section on problems with Pyrex

http://www.consumeraffairs.com/homeowners/pyrex.html


Flip - 27-4-2009 at 04:18

Up to today I have understood Pyrex and borosilicate to be synonymous. The very reason that the Pyrex brand name took off was that it WAS borosilicate glass, the tough stuff. Looking at their wiki page, Corning sold their consumer products division in 1998 (fairly recently, in the history of the brand) and that is when they began using this soda lime glass shite.

Yeah before it happened i heard that sound you hear when something boils to dryness, as if you had just spit on your hotplate. I heard it several times in succession before the pop of the explosion.

So i'm thinking that it started with a small stress fracture that allowed small amounts of water to begin vaporizing underneath the dish. I don't know much about the physics of this, but I'm guessing that it was this vapor that blew it apart.

The funny part is that the mason jar I used withstood those same temperatures just fine, I was actually able to go much higher. So the glass from Ball Co. and I would wager even my pickle jars is actually quite superior to what they are passing off as pyrex these days.

In any case i was spritzed with water and glass shards, which I notice have given me a few nics around the legs, and one on top of my head! Thankfully I was wearing glasses. You know I pride myself on lab safety and being responsible in the laboratory. It's what I am paid to do. After this happened I just couldn't feel more foolish. Damn them!


[Edited on 4/27/09 by Flip]

Sauron - 27-4-2009 at 04:41

Pyrex is a trademark of Corning
Kimax is a trade name of Kimble

Both are borosilicate

DO NOT USE COOKING WARE IN LAB even if labeled Pyrex

For your own safety do not buy dodgy eBay glassware

watson.fawkes - 27-4-2009 at 04:58

Quote: Originally posted by Flip  
Looking at their wiki page, Corning sold their consumer products division in 1998
The following is at the bottom of most all the pages on the site pyrexware.com:
Quote:
PYREX® is a registered trademark of Corning Incorporated used under license by World Kitchen, LLC

watson.fawkes - 27-4-2009 at 05:19

Quote: Originally posted by not_important  

and a consumer protection site has a section on problems with Pyrex

http://www.consumeraffairs.com/homeowners/pyrex.html
Reading this page, it was apparent that Pyrex-branded cookware is made with tempered glass, because of its mode of failure. The Wikipedia page on Pyrex concurs. A reasonable introduction to tempered glass is on Wikipedia at Toughened glass. As an example, Prince Rupert's drops are made of tempered glass.

Apropos of the present situation, failure of tempered glass may occur long after the damage that caused the failure. A tiny scratch can take quite a while to propagate inward. No proximate thermal stress need be present, either. I once had a piece of glass explode inside the kitchen cabinet, spontaneously.

Flip - 27-4-2009 at 06:59

Apparently thousands of people over the last ten years have had their Pyrex (TM) bakeware explode during regular use, causing various damage to kitchens worldwide. It appears also that hundreds have been injured.

I, for one, will not be using these products anymore. Bakeware that violently explodes in the dishwasher? On the shelf at room temperature? It used to buy that you buy your bakeware and you can keep it 20 years. What kind of investment is Pyrex? It's like a glass shrapnel time bomb.

In lieu of an online grassroots campaign for a world-wide class-action lawsuit, can someone then tell me what brands out there are still borosilicate? I have to replace my bakeware and i'll be damned if i'm going to buy more Pyrex.

smuv - 27-4-2009 at 08:21

borosilicate can be distinguished from soda lime glass by looking at the cross section of the glass, if the color is blue/green it is soda lime; if it is nearly clear then it is borosilicate.

That being said, before this, I would have totally trusted any pyrex bakeware on a hotplate without thinking twice.

[Edited on 4-27-2009 by smuv]

User - 27-4-2009 at 08:59

Well the old fashioned coffee pot is still made boros. i have 2 that are actually made by scott.

hissingnoise - 27-4-2009 at 09:56

I have some heavy pyrex jugs and viewed edge-on a cool blue tint is very noticable; any hint of green should raise suspicion when buying this stuff.
My jugs can handle any heat thrown at them. . .

unionised - 27-4-2009 at 11:57

Is it just me or is there a difference between thin glass used in lab beakers and thick glass used as cookware?

BTW, re. the title
http://www.lovehoney.co.uk/store.cfm?cat=13

[Edited on 27-4-09 by unionised]

hissingnoise - 27-4-2009 at 12:44

Fuck Pyrex cockware indeed, unionised. . .
All they're missing is a phone in the base---a hotline!!!
Let's just hope they don't shatter under stress

[Edited on 27-4-2009 by hissingnoise]

GoatRider - 27-4-2009 at 15:01

I think those had better stand up to heat too...

hellfire23 - 27-4-2009 at 15:32

I'd find the guy and sue him for endangerment.

EDIT: http://www.consumeraffairs.com/news04/2006/03/pyrex_panic.ht...


[Edited on 27-4-2009 by hellfire23]

jmneissa - 4-5-2009 at 15:09

Hey has anyone else noticed that pyrex scratches really easily. For example the other day I was using a clean beaker and was stirring the mixture with the thermometer I was using and when I was done and washed out everything when I held it up to the light there was a ring of scratches in the bottom half. I think from no on I am going to wrap the end of my stir rod with a small amount of Teflon tape. But has anyone else noticed this?

Saerynide - 4-5-2009 at 19:50

Yeah, I had a brand new beaker. After stirring, it looked like it was scrubbed with steel wool -_-

tryptamine - 7-5-2009 at 15:46

Well what would you expect when you are using the dish outside of the manufacturers stated uses.

Normally I would be the first person to use an item for other than its intended use but I try to know enough to determine if an item is suitable.

Pyrex baking dish, thick, lots of stress on differential heating, meant to be heated in an oven where the whole unit is at the same temperature, not meant to be cooled quickly in water or used on a stovetop.

Pyrex labwear is not only made of low expansion borosilicate but it is made of very thin walled glass, this is not for cost savings, this is to minimize stresses when the glass is differentially heated. This is also why I call bullshit on people that say thin glass is cheap and dangerous. The only dangerous labwear is that which is scratched, nicked or made with imperfections.

You did something foolish and have no right to be pissed off, but you did learn something.

In my line of work in a research/industrial setting I've seen engineers buy perhaps 30 pyrex baking dishes to store 100 degree calcine as it exited a furnace. After the first one blew up in the hands of an operator the rest of the dishes ended up in the trash bin.

hissingnoise - 8-5-2009 at 03:34

Quote: Originally posted by tryptamine  

Pyrex baking dish, thick, lots of stress on differential heating, meant to be heated in an oven where the whole unit is at the same temperature, not meant to be cooled quickly in water or used on a stovetop. .

My Pyrex cookware seems to be immune to stresses and changes of temperature---as genuine Pyrex should be. . .
If it fails, it isn't Pyrex!

TheOrbit - 8-5-2009 at 04:38

bad pyrex :D

hissingnoise - 8-5-2009 at 05:04

You mean bad pseudo-Pyrex. . .

grndpndr - 8-5-2009 at 12:22

Sauron

For your own safety do not buy dodgy eBay glassware

[/rquote] Id assumed if labeled/advertised borosilicate glass
Id be safe.Im contemplating buying a distilling apparatus.1000ml flask ,200-300 ml condenser,500ml RB flask ,connectors and adapter for included thermometer @
around $125 +/- given the specific distributor.I assume its chinese borosolicate but I havent had any problem with my budget driven purchases of chinese borosilicate no name glassware OT a seperatory funnels poor QC of valve dimensions.Specific brand names I should look for?I see also on e-bay higher priced equivalents (quantitatively) for About$300 +.As I intend to use the equipment for corrosive liquids Im not looking forward to glassware failures.

As i mentioned ive been using chinex borosilicate glassware without incident given proper precautions same with coffee pots withstanding rapid temp change.Also canning jars seem to stand up well with a bit of restraint.

DJF90 - 8-5-2009 at 12:50

Go for Quickfit if you're UK (or generally Europe?), or Ace, Pyrex or Corning for the US.

grndpndr - 9-5-2009 at 06:30

Most equipment that catches my eye pricewise doesnt advertise a maker(simply borosilicate glassware) however I have found a few lab supply companys that will either name the glassware or lose a sale.
Thanks for the names of reliable companys.

Ive located the name of that chin glassware although Im sure it floats around under several brand names,Bomex.
BOrosilicate/pyrEX.power of suggestion?Although honestly it hasnt failed using proper lab precautions over several years
other than normal accidents/carelessness

[Edited on 9-5-2009 by grndpndr]

Pyrex

MadHatter - 9-5-2009 at 12:41

I had a so-called Pyrex casserole dish made by Anchor Hocking explode on me.
Strangely, I have older(dark brown tinted) glass cookware that have no labels but
never gave me a problem under any circumstances. As for lab glass, use Bomex only
for applications that don't involve heat.

497 - 9-5-2009 at 13:24

I have a 1000ml Bomex Erlenmeyer which I use regularly to boil down H2SO4. It gets heated to 300*C for long periods of time directly over a propane flame... I've probably used it 30 times for that purpose, never had a problem. So am I just lucky?

watson.fawkes - 9-5-2009 at 14:10

Bomex is a borosilicate glass: http://www.tzbomex.com/en/xn.htm.

grndpndr - 10-5-2009 at 14:56

I generally use a hotplate and screen arrangement but for the same purpose and worse w/o incident .As I say the only losses have been thru carelessness,so far.

nothing lasts forever

jimwig - 10-5-2009 at 15:15

the best in borosilicate still has to conform to the laws of physics.

a crack or chip almost invisible can cause catastrophic results.

also one should use a diffusion type of layering even when using a supposedly safe source of heat - like the corning ceramic surfaces.

and in closing nothing lasts forever and even corning-- both glass and other things have a finite lifetime.

i jusst lost a 10 x 10 inch corning combo stirrer/hotplace. the ceramic top fractured into about a dozen large pieces.

grndpndr - 10-5-2009 at 16:31

Of course something with obvious flaws even scratches can be suspect and I always use the approach you describe either a screen on a hotplate,I personally think oilbaths are dangerous themselves but Ill use a sandbath etc.but I never expose my glass to a direct heat source and try to protect myself more than my glassware.Particularly not to forget your lungs.Glassware can be replaced, lung,cornea,and skin grafts/ transplants not so easy.Im sure yor all aware of the danger but if it causes a bulletproof youngster to consider the implications its the best contribution I could make.Just because it doesnt kill outright or cause a hospital visit doesnt mean the damage isnt cumulative.Just take care like you would with any dangerous equipment etc.Dangers that are common knowledge now werent when I was a youngster many are just know paying the price.Rant exhausted.




[Edited on 11-5-2009 by grndpndr]

jmneissa - 18-5-2009 at 13:33

Well I have to vent here as well I just got some brand new flasks today including some expensive two neck flasks. Well I was washing them out and set them upside down to dry when one tipped over and shattered! I can't believe it. It just falls over and breaks! Come on this is ridiculous I mean falling off a table okay but just rolling over? It's a complete joke now I am on the phone with glass companies trying to get it repaired because there is no such thing as a "warranty" with glassware... Even then they say it could cost more than the flask is worth to repair it!! Aghhhh!!!! So annoying basically $66 + SH just went down the drain...

Simax glassware, from Czech Republic

dann2 - 20-5-2009 at 09:14

Hello Folks,

Looks like some are having a 'smashin' time eh :P

Just wondering what you's think of Simax wear (make in the Czech Republic).
See ebay here.

or is a case of Fuck Simax.

Dann2

Lambda-Eyde - 20-5-2009 at 09:52

Most of my glassware (except for the ground glass) is Simax brand, but I haven't used it much, so I can't really tell much about its quality.
From what I can see though, the beakers and flasks appear very sturdy with nice markings.

An interesting sidenote: I saw a 50l Chemglass 3-neck jacketed flask with a bottom drain on eBay - which also had the Simax logo on it!

dann2 - 20-5-2009 at 15:06

Hello,
For the (perhaps) dodgey 'Pyrex' home cook glasswear a test could be done whereby the vessel is put into an oven and heated to 200&degC, taken out, and thrown into a large bucket of cold water.
Would that sort the bad stuff from the proper Pyrex glasswear?
Dann2

User - 20-5-2009 at 15:24

Well the fact that crappy glass would never survive this might conclude something, still would you really boil liquid in it that boils beyond 300 degrees, i certainly would feel unconfortable.
Well even though pyrex might be sucky, I still use some glass in my lab that isnt boro or anything similar , I just dont stress it as much as the stuff i know it can deal with it.
Also i would never use old glassware for scary operations.
Its just a matter of thinking before doing.

Formatik - 20-5-2009 at 16:14

Quote: Originally posted by dann2  
Hello,
For the (perhaps) dodgey 'Pyrex' home cook glasswear a test could be done whereby the vessel is put into an oven and heated to 200&degC, taken out, and thrown into a large bucket of cold water.
Would that sort the bad stuff from the proper Pyrex glasswear?
Dann2


I would expect most glass to break under that condition. I was heating a 1L flask some time ago (Schott glass mind you, though several years old) on a hot plate (it reaches around 500 deg. and above), and just after removing the flask and setting it on a surface (not cold, but cooler than the hot part) and it cracked immediatley. The heat resistance of household glassware depends on its designated use (borosilicate glass tea containers) or glass pots for heating food on the stove. Compared to bakeware like Pyrex I would expect those to be much more thermally stable.

Here is a statement about Pyrex glassware from their website:

Quote:
Avoid Sudden Temperature Changes to your Glassware. To avoid the risk of breakage due to a sudden temperature change to your Pyrex glassware, DO NOT add liquid to hot glassware, place hot glassware on a wet or cool surface, or handle hot glassware with a wet towel, wet potholder or other wet cloth. ....

DO NOT Use On or Under a Flame or Other Direct Heat Source, including on a stovetop, under a broiler, on a grill or in a toaster oven.


http://www.pyrexware.com/index.asp?pageId=104

[Edited on 21-5-2009 by Formatik]

dann2 - 21-5-2009 at 07:19

Hello,

Some info. here regarding Simax glass.

Dann2

Not all Pyrex is made from Borosilicate

CHRIS25 - 29-4-2012 at 11:34

I was thinking (for the time being) to use a pyrex jug for one of my reactions which is exothermic. But upon doing some instinctive research I was horrified to read that the company who took over Pyrex (World Kitchen) use hardened soda lime and still call this pyrex.

As I have researched and found that hardened soda lime is well... harder than standard soda lime glass. But the fact remains that it seems I would not be able to trust a cookware jug with the pyrex label, because it is not really the borosillicate composition.

Is all this true. Only asking because I do not have any chemistry beakers at this moment and for a small reaction I thought that buying a pyrex jug would be ideal just for the moment.

hissingnoise - 29-4-2012 at 12:35

Quote:
I thought that buying a pyrex jug would be ideal just for the moment.

Today's pyrex jugs are made of tempered soda-lime and won't withstand sudden changes in temperature as borosilicate will . . .

Funkerman23 - 29-4-2012 at 12:38

Pyrex still only uses borosilicate glass for their labglass line but all of their cookware has changed over to the hardened soda lime/"tempered" glass for some unknown reason. all I know of are rumors as to why they did that( so sadly I cannot offer concrete reasoning other than I have confirmed the cookware isn't the usual borosilicate) but if you buy their flasks, beakers and other labware then you can rest easy.

watson.fawkes - 29-4-2012 at 15:02

Quote: Originally posted by Funkerman23  
Pyrex still only uses [...]
The phrase "Pyrex uses" is nonsense. Pyrex is a brand name, not a company. The original trademark was owned by Corning. Corning sold off the rights to the brand name for retail cookware sold in the US a few year ago. At the time, they hadn't done so for all global markets, though I don't know what the status is for that now. Corning still sells labware with the Pyrex name.

Fossil - 29-4-2012 at 17:37

When World Kitchen took over the Pyrex brand, it started making more products out of prestressed soda-lime glass instead of borosilicate. This was done to save money, lower prices, and to cut down on manufacturing costs. The soda lime they use now is pre-stressed from the inside, although when you heat it, it still expands like regular soda lime glass would. It wont shatter immediately, but it can only expand up to a point until the inner-stress is too strong.

CHRIS25 - 30-4-2012 at 06:41

thanks Fossil, off to order some proper glass now!!!

Fossil - 30-4-2012 at 13:06

Good! I almost made the same mistake once, nearly used a 1 liter pyrex measuring cup for a high temperature oil bath. Good thing I didn't, would have been quite the mess!

chucknorris - 2-5-2012 at 13:50

Just blew up a process when heating (luckily powder form) stuff by using the flat PYREX jug. The heating was likely OK, but when I took it off, the bottom fell off. For 4 years have had 4 of these items and I managed to crack all of them in normal processes, but got my money back from the shop.

nerdalert226 - 9-5-2012 at 17:01

Thats crazy! how do they pass off pyrex as hardened soda lime!?

gutter_ca - 10-5-2012 at 09:45

From Pyrexware.com :

"Pyrex glass bakeware is, and has always been, durable, reliable and safe.
The U.S. Consumer Products Safety Commission conducted an investigation in 2008 and concluded that Pyrex glass bakeware does not present a safety concern.
While both borosilicate and soda lime are appropriate compositions for glass bakeware, heat strengthened soda lime is more resistant to impact breakage - the far more likely cause of consumer injury according to national emergency room data.
World Kitchen did not change the product composition for Pyrex glass bakeware.
Pyrex glass bakeware has been made – first by Corning Incorporated and now by World Kitchen – using the same soda lime composition and heat-strengthening process for more than 60 years.
World Kitchen has always manufactured Pyrex glass bakeware in the U.S. and our packaging proudly displays the American flag and the “made in the USA” label.
World Kitchen, which purchased the Pyrex consumer products business from Corning Incorporated in 1998, is a U.S. company based in Rosemont, Illinois"

Dr.Bob - 10-5-2012 at 11:42

That is partly correct, Corning had made SOME of its bakeware out of soda lime glass for the past 60 years, but now ALL of it made in the US is soda lime glass. But much of the Pyrex bakeware was borosilicate glass up until around 1988, when Corning started cheapening it, and then they sold it to World Kitchen, who may or may not have appreciated what the difference is. Either way, household bakeware is not useful for lab work now.

Most Pyrex labware is now made in Germany or England, as they don't manufacture much borosilicate glass in the US now, due to environmental issues and such. I don't know if Ace, Chemglass or other companies now make their own, buy the raw glass in the US, or import it all now.

watson.fawkes - 10-5-2012 at 14:11

Quote: Originally posted by Dr.Bob  
Most Pyrex labware is now made in Germany or England, as they don't manufacture much borosilicate glass in the US now, due to environmental issues and such. I don't know if Ace, Chemglass or other companies now make their own, buy the raw glass in the US, or import it all now.
Insofar as I am aware, there are only four major primary producers of raw borosilicate glass, with their associated brand names: Schott (Duran), Corning (Pyrex), Kimble (Kimax), and Kavalier (Simax). Kimble Chase evidently also owns Bomex, as I found out on their company location page; it was news to me. I don't know where the factories are now, but the companies are German, US, US, and Czech, respectively. The compositions of the various glasses aren't identical, but they're close, and they have closely matching coefficients of thermal expansion, so they can be worked interchangeably. Disclaimer: There are likely other producers outside of North America and Europe that I'm not aware of.

Ace and Chemglass are fabricators; they buy their glass from other producers. I don't know who their suppliers are.

S.C. Wack - 10-5-2012 at 15:53

Quote: Originally posted by Dr.Bob  
Most Pyrex labware is now made in Germany or England, as they don't manufacture much borosilicate glass in the US now, due to environmental issues and such.


Dubious statement is dubious; reference?

The usual over and over
http://www.sciencemadness.org/talk/viewthread.php?tid=3384

Arthur Dent - 11-5-2012 at 04:38

I've had "pyrex" brand glass shatter, but it was entirely my fault.

I was preparing basic Copper Carbonate, my resulting mixture was put in a glass baking pan (8X8) directly on a hotplate element, and upon dessication of the mixture, I did kind of a nitwit thing without thinking...

I took the pan away and deposited it on the concrete floor. Then 30 seconds later, I hear a little noise... crik TCHING! The damn thing just split cleanly in half. That was my favorite drying pan! :( The temperature difference was simply too much and the thermal shock did its dirty deed.

I replaced the pan since, opting for a used pan that I bought at a thrift store for a buck, and it looked very old but not scratched. I feel more confortable with a pan that saw a lot of usage than a brand new pan that might not be up to specs.

So far the old pan has performed its duties without a problem, but I don't remove it from the heat without proper thermal isolation. Usually, I just deposit it on an old newspaper, which prevents the excessive surface temperature differences.

But I have to admit that I do not "bake" the glassware at extreme temperatures, I mostly use this to boil away water from solutions outdoors on my porch, and never at the max temperature of the hotplate.

Robert

Dr.Bob - 11-5-2012 at 06:11

Quote: Originally posted by S.C. Wack  
Quote: Originally posted by Dr.Bob  
Most Pyrex labware is now made in Germany or England, as they don't manufacture much borosilicate glass in the US now, due to environmental issues and such.


Dubious statement is dubious; reference?

The usual over and over http://www.sciencemadness.org/talk/viewthread.php?tid=3384


The main reason for changing to soda lime glass is cost of materials, higher working temps (thus higher energy costs), and shorter life of equipment, but for some examples of the environmental issues of borosilicate glass production see:

http://thestatsblog.wordpress.com/2008/02/29/pyrex-soda-lime...

http://www1.ifc.org/wps/wcm/connect/384e20804885574ebc0cfe6a...

malcolmf - 12-5-2012 at 04:29

Quote: Originally posted by Dr.Bob  
That is partly correct, Corning had made SOME of its bakeware out of soda lime glass for the past 60 years, but now ALL of it made in the US is soda lime glass. But much of the Pyrex bakeware was borosilicate glass up until around 1988, when Corning started cheapening it, and then they sold it to World Kitchen, who may or may not have appreciated what the difference is. Either way, household bakeware is not useful for lab work now.


Ah, then the stuff I've got might be OK. I discovered it abandoned in my deceased mother's outhouse, and, from vague memories of it, it must be about 20-30 years old. Not a scratch or chip on any of it. Just a 10+ year thick layer of dust and grease. Saucepans, and even a frying pan in a heavy brown glass. If I recall correctly they were intended for use directly on a cooker ring: (a frying pan??!) and decades old vague memories associate them with a brand name of "Vision".

Ah, I've just googled it, and it's Corning borosilicate from before the change to soda glass. A treasure trove!
This will be very handy.

grndpndr - 12-5-2012 at 14:48

Quote: Originally posted by tryptamine  
Well what would you expect when you are using the dish outside of the manufacturers stated uses....



You did something foolish and have no right to be pissed off, but you did learn something...

In my line of work in a research/industrial setting I've seen engineers buy perhaps 30 pyrex baking dishes to store 100 degree calcine as it exited a furnace. After the first one blew up in the hands of an operator the rest of the dishes ended up in the trash bin...


It would seem the 'engineers' "in your line of work".. "did something foolish"...hopefully they learned something as well!My wish was that the engineer that selected the dishes was the the one who held the dish that exploded ratether than a min wage operator.:D

The definition of smug comes to mind.I dont wish anyone ill but when that accident happens!LOL

[Edited on 12-5-2012 by grndpndr]

[Edited on 12-5-2012 by grndpndr]