Teach Soap

We are always telling everyone to NOT use glass (even pyrex) to mix or hold the lye bath in, or to mix your soap batter in. The lye and the extreme heat of the soap batter etches the glass over time, and eventually will cause it to crack or break, which could occur when you have your lye bath or batter in it, meaning that you may spill the contents on yourself, your animals, your kids, etc. At the very least it would cause a big mess.
Anyway, someone posted this video on another forum I belong to and I thought I'd share it here. While this video shows the effects of lye on plain glass, the same thing will happen with tempered glass, or pyrex, it just takes a bit longer. It will etch the tempered glass over time, and you will not know how many times that it will take to cause it to break.
FYI; the newer pyrex measuring cups are plain glass, just thick glass. They will etch faster than the old pyrex which was made from specialty glass. So, unless you are using your Grandmas pyrex, this video will be your glass one day! If you do have the old kind, yours will last longer, but then again, yours has been used a lot more, so ........maybe not!

http://www.youtube.com/watch?v=nmktRTHL1NA

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Remember, it's not just that we weather the storm, but how we dance in the rain.

Tammy

Darn
I'll have to find a good/heavy picture with a spout for batter.
I've been using a pyrex bowl with spout.
It's hard to pour into the 12 bar silicone mold using a pot,
and I have to pour quickly as each square gets a little thicker.
Guess I could invest in a loaf mold too......sigh

Thanks for the info!

Birdie, I use a simple, less than 4$, plastic pitcher that is Polypropylene and rated a #5. I got it at walley world and my 82 oz (oils) batch fits nicely in there, with plenty of head space. It is easy to pour from it into the individual molds, and I use it for the 5lb loaf molds too. That way I can save my big ss pot for the big batches! So you dont have to go expensive to have something that holds up and works well!

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Remember, it's not just that we weather the storm, but how we dance in the rain.

Tammy

Never use pyrex or glass for your lye water or raw soap batter. I posted this in a sticky. viewtopic.php?f=2&t=3800

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Irena
Closed minds are like faulty parachutes; they refuse to open.

perhaps you should add the link to this video to your sticky Irena. Some people need to see for themselves and the video allows that!

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Remember, it's not just that we weather the storm, but how we dance in the rain.

Tammy

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Irena
Closed minds are like faulty parachutes; they refuse to open.

Yes, it is true that any tool, when used in a manner not intended, will fail. Heating lye up to "molten" temperatures and submerging a glass in the lye will indeed, melt the glass as shown in that YouTube video. Steel and virtually any material will fail at molten temperatures as well. In sodium hydroxide's case, to get it to 'molten' temperatures, it is roughly 300 degrees centigrade or 572 degrees fahrenheit.

What we do as soap makers is vastly different. We use sodium hydroxide diluted by 60-70% and temperatures typically are below 180 degrees for this diluted solution.

While some soapers prefer to soap with alternative materials, I am comfortable soaping in heat resistant glass containers. I have confirmed multiple times over the years, with both KitchenAid (Whirlpool Corp) and Pyrex, that adding lye (sodium or potassium hydroxide) to water and using it with their products is within their safety and testing zones.

However, each soap maker is different in their preferences for soaping. What works for one soap maker (70% coconut oil for one person, never over 15% for another, for example) won't work for another and I urge every soaper to soap well within their personal comfort zone.

While I am fine using heat safe glass for my lye water and have been using the same KitchenAid and Pyrex containers for 15+ years now, there are excellent alternatives out there such as this stainless steel pitcher () and this heat safe plastic container ().

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Happy Soaping!

Anne-Marie
blog: www.soap-queen.blogspot.com
supplies: www.brambleberry.com

"have been using the same KitchenAid and Pyrex containers for 15+ years now"

@Ann Marie, I believe that your comment above is what makes the difference. From my understanding, pyrex has changed their product and the newer pyrex is not made from the same specialty glass that it once was. The old pyrex was made from the same type of glass that beakers for chemistry endeavours was made. Very sturdy and well within parameters. But the new ones are not. Therefore the newer ones will etch over time and eventually break. Certainly they will not melt as quickly as dipping it into a lye concentration, but over time the etching will cause microfractures that will eventually cause the material to break and they could break when your pitcher is full of lye.

On another forum I belong to a few people have stated that their "pyrex" lost its bottom coming out of the microwave (with hot water in it) and other similar incidences. I believe even Irena has commented on this forum that she had an incident with a glass container breaking due to etching (forgive me if I have that wrong, my memory isn't what it once was).
I don't want to be a nervous nelly, but I don't want to see any easily preventable accidents either.

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Remember, it's not just that we weather the storm, but how we dance in the rain.

Tammy

I have over 25 Pyrex containers upstairs in the Soap Lab. Some are old. Some are new. As the blog, the company and the sheer volume of projects I do now have grown, the lab and all the glassware has grown with me. =) The projects that you see on my blog are ]the teensiest tip of the ice berg for how much cold process soaping gets done here. I + the Brambleberrians make an insane amount of soap weekly. That said, I have not seen any difference in their performance and the switch for the glass was made in 1998, which probably dates most of my Pyrex as the new glass. My last contact with Pyrex on this issue was the last time this was addressed in the forum (October 2012) and they confirmed that adding lye to water in their Pyrex, as currently manufactured, was considered safe by them.

I, too, have had Pyrex shatter on me in them microwave when used in a manner not intended (see blog post here: ) - mostly empty, to melt beeswax. Additionally, all heat safe glass (any brand) can shatter when it is oven-hot and placed on a cold surface because glass is a brittle material. That is usually warmer than the 180 our lye water gets to but a good caveat to know.

I don't own stock in Pyrex (though given how much I use them, maybe I should! =) ). My comfort level with utilizing heat resistant glass while soaping is my opinion based on my experience and research. Each and every soaper should do what they feel comfortable doing with their soap and the process they use to make it.

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Happy Soaping!

Anne-Marie
blog: www.soap-queen.blogspot.com
supplies: www.brambleberry.com

Thank you for that info, I guess, like most everything on the net, there is conflicting info out there. If yours is from the new stuff and the company says this is within normal parameters, I apologize for the misinformation I provided. I had always used pyrex until my old one was hijacked by my kids and I read about the new ones not being good for soaping. While I like my plastic pitcher for the pourability and its light weight, I will pass along the info you provided and stop perpetuating the false info.
I would still exercise caution when heating in the microwave though, as they also give an uneven heat concentration, so that certainly could be an issue with etching.
Thanks again, and my apologies again.

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Remember, it's not just that we weather the storm, but how we dance in the rain.

Tammy

After my Pyrex shattered in the sink with lye water in it, I tend to be on the cautious side and use heavy duty plastic or stainless steel.
The old Pyrex is/was borosilicate glass. The new Pyrex is made from soda-lime glass. That's a big difference.
Borosilicate glass has a low thermal expansion. Soda-lime glass is about 1/3 of that. This means that at higher temperatures, borosilicate glass will expand much less then the new soda-lime glass and will be more prone to shattering.

One interesting thing between the two; when borosilicate glass breaks, it usually breaks into large pieces. When soda-lime glass breaks, it shatters into many tiny pieces, which are harder to clean up.

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Irena
Closed minds are like faulty parachutes; they refuse to open.

Oh gosh, no need to apologize LavenderLady. It's all personal preference and we all need to soap within the parameters we're comfortable with.

After reading Irena's note, I can understand why she would be leery of soaping with Pyrex. What a scary situation - glad it was in a sink, Soap Buddy!

Cautious soapers are happy soapers =)

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Happy Soaping!

Anne-Marie
blog: www.soap-queen.blogspot.com
supplies: www.brambleberry.com

Although I don't use mine for soap batter, I have some big red mixing bowl things with spouts and handles. They've pretty sturdy plastic, and I think I got them at Walmart.

I'll see if I can post a picture later.

Anita[/quote]

That sounds like something I'd use. I really need a spout.
I'll look at Walmart.
I like mixing my lye water in glass because I hate it when
lye bounces around....even when I use dryer sheets to wipe plastic,
sometimes they still do that. Of course lye flakes could be a safer option.

I mix my lye water in a plastic pitcher but I mix my soap batter in a big pyrex measuring dish. I haven't had any problems and by the time everything is cooled down it is way below the recommended safe heat levels.

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Haven