Very nice information about glass.

[superharmonix]

I was re stocking some beakers, Pyrex, and such yesterday and found this site: http://www.scilabware.com/FAQ/Category/Glassware/

There is a ton of great information on borosilicate glass, (like what Pyrex is made from as well as certain lab beakers), and some information regarding heating/cooling, and some great safety tips.  I thought I would share with my fellow addicts here.

-Shawn

[superharmonix]

Ummm.  I re-read that and I feel I should clarify here.   

I mean BAIT POURING addicts.

[412BaitCo]

Yeah talking about Chemistry beakers and such you should probably be specific on that lol.

[wubbawurm63]

I have been wanting to get a few beakers, but do they work ok in the micro. for remelting sprues and scraps?

[hawgthumper]

JMHO, but I think I'd stay with Pyrex. It's made to take the heat.

[wubbawurm63]

Thanks.

[superharmonix]

Actually, the right beakers do work in the microwave- I use them for clear dips, etc.  You just have to make sure they are borosilicate glass.  Pyrex is made from borosilicate glass.  Same thing....Like I said I mainly use them for dipping baits- frog bodies, tubes, swims, etc...  If you buy a beaker that is thin but tall, you waste A LOT less plastic when dipping baits.  Thinner width, taller height = less plastic per heat = less scrap.

[hawgthumper]

Actually, the right beakers do work in the microwave- I use them for clear dips, etc.  You just have to make sure they are borosilicate glass.  Pyrex is made from borosilicate glass.  Same thing....Like I said I mainly use them for dipping baits- frog bodies, tubes, swims, etc...  If you buy a beaker that is thin but tall, you waste A LOT less plastic when dipping baits.  Thinner width, taller height = less plastic per heat = less scrap.

So your beakers are made of Pyrex? Thanks for making my point.

[412BaitCo]

I've heard that Pyrex is no longer made of borosilicate unless you buy the lab grade?

[superharmonix]

So your beakers are made of Pyrex? Thanks for making my point.

Hawg, glad to help you out. 

Not to get too technical, but Pyrex is one of the trade names for borosilicate glass.  One quote I found: "Borosilicate glass is a type of glass with the main glass-forming constituents silica and boron oxide. Borosilicate glasses are known for having very low coefficients of thermal expansion (~3 × 10?6 /°C at 20°C), making them resistant to thermal shock, more so than any other common glass. Such glass is less subject to thermal stress and is commonly used for the construction of reagent bottles. Borosilicate glass is sold under such trade names as Simax, Pyrex, Endural, Schott, or Refmex. 

What I was trying to say was more geared for the peeps that are just starting, or maybe don't know about the glass properties.  That link I posted at the start of this thread has some great info!

My line of thought also was, when a lot of folks hear "Pyrex" all they think of are 1 cup, 2 cup, 4 cup, or if you are like Grimp, 6 cup size measuring cups.  A lot of people, including me until somewhat recently, just don't realize there are other alternatives.  I was dipping all my baits in these little Pyrex custard dishes, which are not deep enough for tubes, dipping knives for swims, etc.  Borosilicate beakers, 100mL, 250mL, or whatever size fits your application work AWESOME because there is so much less waste.  You are heating up less volume of plastic since the beakers are thin in diameter, but you end up having more room vertically to dip your baits in.   

The bottom line is so always keep safety at the top of your list, all the way down to each detail, and you stay out of the hospital!  IF you can also save on material costs, or labor costs while doing it, then yee-haw!

[superharmonix]

I've heard that Pyrex is no longer made of borosilicate unless you buy the lab grade?

412- I heard this too.  Looks like they now use soda-lime glass.  I found this: Older clear-glass Pyrex manufactured by Corning before 1998, Arc International's Pyrex products, and Pyrex laboratory glassware is made of borosilicate glass. According to the National Institute of Standards and Technology, borosilicate Pyrex is composed of (as percentage of weight): 14% boron, 51% oxygen, .3% sodium, 1% aluminium, 38% silicon, and less than 1% potassium.[9][10]
According to glass supplier Pulles and Hannique, borosilicate Pyrex is made of Corning 7740 glass, and is equivalent in formulation to Schott Glass 8830 glass sold under the "Duran" brand name.[11] The composition of both Corning 7740 and Schott 8830 is given as 80.6% SiO2, 12.6% B2O3, 4.2% Na2O, 2.2% Al2O3, 0.04% Fe2O3, 0.1% CaO, 0.05% MgO, and 0.1% Cl.
Pyrex glass cookware manufactured by World Kitchen is made of tempered soda-lime glass instead of borosilicate.[12] World Kitchen justified this change by stating that soda-lime glass was cheaper to produce, is the most common form of glass used in bakeware in the US, and that it also had higher mechanical strength than borosilicate—making it more resistant to breakage when dropped, which it believed to be the most common cause of breakage in glass bakeware. Unlike borosilicate, it is not as heat resistant, leading to an increase in breakage from heat stress.[5][13][14]
The differences between Pyrex products depending on manufacturer has also led to safety issues—in 2010, the Consumer Product Safety Commission received several complaints by users reporting that their Pyrex glassware had shattered at high temperatures. The consumer affairs magazine Consumer Reports investigated the matter after obtaining copies of the complaints, determining that the complainants had in fact been using World Kitchen-produced Pyrex products, and had incorrectly assumed that they would have the same characteristics and strength as their borosilicate counterparts.[15]

...so the million dollar question is, how much heat can the post-1998 "Pyrex" handle?

[412BaitCo]

412- I heard this too.  Looks like they now use soda-lime glass.  I found this: Older clear-glass Pyrex manufactured by Corning before 1998, Arc International's Pyrex products, and Pyrex laboratory glassware is made of borosilicate glass. According to the National Institute of Standards and Technology, borosilicate Pyrex is composed of (as percentage of weight): 14% boron, 51% oxygen, .3% sodium, 1% aluminium, 38% silicon, and less than 1% potassium.[9][10]
According to glass supplier Pulles and Hannique, borosilicate Pyrex is made of Corning 7740 glass, and is equivalent in formulation to Schott Glass 8830 glass sold under the "Duran" brand name.[11] The composition of both Corning 7740 and Schott 8830 is given as 80.6% SiO2, 12.6% B2O3, 4.2% Na2O, 2.2% Al2O3, 0.04% Fe2O3, 0.1% CaO, 0.05% MgO, and 0.1% Cl.
Pyrex glass cookware manufactured by World Kitchen is made of tempered soda-lime glass instead of borosilicate.[12] World Kitchen justified this change by stating that soda-lime glass was cheaper to produce, is the most common form of glass used in bakeware in the US, and that it also had higher mechanical strength than borosilicate—making it more resistant to breakage when dropped, which it believed to be the most common cause of breakage in glass bakeware. Unlike borosilicate, it is not as heat resistant, leading to an increase in breakage from heat stress.[5][13][14]
The differences between Pyrex products depending on manufacturer has also led to safety issues—in 2010, the Consumer Product Safety Commission received several complaints by users reporting that their Pyrex glassware had shattered at high temperatures. The consumer affairs magazine Consumer Reports investigated the matter after obtaining copies of the complaints, determining that the complainants had in fact been using World Kitchen-produced Pyrex products, and had incorrectly assumed that they would have the same characteristics and strength as their borosilicate counterparts.[15]

...so the million dollar question is, how much heat can the post-1998 "Pyrex" handle?

A ton! I found an article done in a lab on all the major baking glassware companys. They did things like hot cold extremes so on. The funny part was they literally mentioned barrowing old pyrex of of someones "Grandma" and it took over 200 degrees more then any other product. I will have to try to find it. It beat all other companies in all category's of the study.

[412BaitCo]

It was right when I started doing baits and that article is what actually made me go with silicon cups. I can't seem to find it again.

[floridagrimp]

whew...bottom line, is the Pyrex we buy at Wally World ok to use repeatedly at high temp??? (and the yr I bought it? 2012!)

[hawgthumper]

Borosilicate glass is without question better. I did some research earlier this year on high temperature sight glasses for a pressure pot I'm trying to build, and that's what most of them are made of. So they'll take some seriously high temps.

As for your question Grimp, I think the stuff you buy at Walmart is fine for what we do. Just don't set a hot cup of plastic on a cold surface! BOOM!

Just one more reason I love my Prestos. It'd be cool of we could come up with a heated pot for doing small batches like with the Pyrex.

Don't pay me any mind SuperH. I was just razzin you a little