# Glass vs Plastic for Soap Batter



## LilianNoir

Before I started making soap I did A LOT of research...and based on that research, I thought it was safe to use a sturdy pyrex glass measuring cup/bowl to mix soap batter (but not lye solution). 

So for my first two batches, that's what I used.

But from a recent post here, I'm seeing lots of seasoned soapers caution against glass even for batter and I had concerns about it myself. 
I'd like to use plastic, but I can't find any plastic mixing bowls that have the plastic code on them. 

I'm concerned that stainless steel pots will be too heavy and difficult for me to pour(I have weak wrists and some issues with my hands).

What do seasoned soapers use to mix batter that isn't metal?
And where do you find it??


----------



## IrishLass

I have a trusty stainless steel bowl, and also a sturdy, opaque/white 8-cup Oxo plastic measuring cup with a grippy bottom, handle and pour spout that I use for soaping. Oddly enough, the plastic Oxo measuring cup does not show a recycle code (probably because of the rubberized grippy bottom?), but for what it's worth, it's lasted me through about 5 years of soaping and counting. My stainless is still going strong after 13 years of soaping and counting.

Although you'll find lots of youtube videos showing folks soaping in Pyrex or other glass bowls, they're living life on the edge, in effect playing Russian Roulette with their bowl. Sure, it might stand up to your batches fine for a while.....or not. You just never know when it's gonna blow. Too many soapers have reported their Pyrex break on them while soaping, so SMF's official stance is to recommend either plastic or stainless steel instead of Pyrex for safety sake when soaping. Here is an older post of mine explaining why I don't use or recommend Pyrex or any type of glass when making soap (it includes informative links):
*https://www.soapmakingforum.com/threads/dealing-with-glass-advocates.47015/page-2#post-436558 

*
IrishLass


----------



## Susie

If you have a Dollar Tree, or indeed any dollar store such as Family Dollar or Dollar General, they generally have plastic mixing bowls.  They feel kind of flimsy, but there will be either a 2 or a 5 on the bottom.  They often come in sets of 3, small, med, large.  

I also use empty 4 lb lard buckets, I have LOTS of those.  Matter of fact, I masterbatch my oils then weigh the oils into those to get ready for a big soapmaking session the next day.  Plastic 5 quart/gallon ice cream buckets are also a good place to look, I have a couple of those that are the right codes, and usually they have handles.


----------



## earlene

My mixing bowls do have a recycle code on the bottom.  In Florida, you should be able to find some like this somewhere.  I recall seeing them in Dollar Stores and some grocery stores there.  Coded with recycle #2 or 5 on the bottom inside the triangle.

Also Home Depot and such stores have paint mixing plastic containers with coding on bottom that many folks also use for batter.  I recall seeing Home Depot in Florida, too.  Of course, I am not sure how close you are to any of those stores.  Thrift stores are another place to find used mixing bowls, although the only thrift store I've been to in Florida was in a resort area and the prices were often as high as brand new.

You could always use recycled containers like Susie says or order from Amazon or other online seller.

These are similar to some I currently use:






Suitable Home Depot containers:


----------



## LilianNoir

Thanks everyone!
I'd just saw another post about the Home Depot paint containers. For some reason when I think of paint containers I only think of really big ones and it never occurred to me that there would be smaller ones. LOL. 
There's a home depot and three different dollar stores within 5 minutes of my house so I'm going to check them today. I'd gotten a set of what appeared to be really sturdy mixing bowls from Target that look just like the ones you show, @earlene  but they didn't h ave the code. I can imagine they're made of HDPE but... without knowing for sure I'm not sure I should risk it? The ones I got from target also have a grippy bottom which might be why there's no code. 

I also saw someone mention they use a tea pitcher. That sounds ideal with the spout and was something I'd never considered  before for some reason.

Target and one of the dollar stores near me didn't have anything with codes, but I'll take a look at the other two dollar stores. 

What're thoughts on using the bowls from target? They're certainly thick and are microwave and dishwasher safe. I'm thinking of they're dishwasher safe, there's a really good chance they're HDPE...


----------



## earlene

I'd try one of the Target bowls, but perhaps you can find an answer on the Target website for your particular bowls.  They list information and allow for questions.  If you find your set, and ask a question about what type of plastic they are made of AND what is the recycle number for them, they should get back to you pretty quickly, I think. (Maybe not today because of the holiday.)


----------



## Iluminameluna

I've been using large yogurt containers (2lb ones) since I started soaping and they've yet to let me down. They have a 2 or 5, depending on the brand.
I use them for the batter and the lye, both.


----------



## Mobjack Bay

Consumer grade Pyrex isn’t what it used to be!  It’s no longer made from borosilicate glass, which is the type of glass used to make Pyrex glassware for laboratories.  That glass doesn’t expand and can handle almost anything (like boiling acid!).  Consumer grade Pyrex is now made from tempered soda-lime glass, which expands when heated. The expansion can weaken the glass over time and makes it prone to shattering when temperature changes are significant. This change in the way the glass is made occurred after Corning sold the company in 1998.  There’s a very short video here, if you want to watch a measuring cup shattering (the video is the second one, about halfway down in the article).  It’s a really, really bad idea to mix lye and water in glass!



Iluminameluna said:


> I've been using large yogurt containers (2lb ones) since I started soaping and they've yet to let me down. They have a 2 or 5, depending on the brand.
> I use them for the batter and the lye, both.



I have a LOT of large yogurt containers, so thanks for that tip!

I ended up trying the super cheap bowls from the dollar store and they work just fine for me for mixing my oils and lye water.  I’m not sure what the number is, but will check. Edited to add that there is no number on my bowls.

To be as safe as possible, I mix my lye in a stainless steel pitcher that has a handle.  I’m getting a bit more clumsy as I get older and I definitely don’t want to have a container of lye slip out of my hand.


----------



## DeeAnna

And on top of the concerns about pyrex shattering due to etching or temperature stress, the simple fact is glass breaks if you drop it, so I stick with non-breakable containers when possible. No matter what causes glass to break, cleaning up soap batter mixed with shattered glass is a lot more hazardous and troublesome than cleaning up soap batter alone.


----------



## Candybee

I get my soaping bowls, utensils, rubbermaid spatulas, measuring spoons, etc, from Walmart, Dollar Tree, Target, and even the Good Will store. Truth is you can find excellent and cheap soaping bowls without breaking the bank. I love going into the Good Will store and seeing what I can score for the day. I actually got my large soap mixing bowl there. Its white, has a pour spout and handle and is large enough for my 5 lb batches. I got it for less than $2 and later saw the exact same bowl at Walmart for about $10. Woohoo!!

Wanted to add I've even mixed large batches up in the 7lb oil pails I used to get before I went bulk. When I used to buy oils by the 7lb pail I just washed out and saved the pails cause I thought someday I could use them. I use them all the time so glad I did save them. But they also work great for making soap in them too.


----------



## MGM

My understanding was that it wasn't a good idea to mix LYE in glass or non HDPE plastic, but that soap batter is ok? I don't know if my dollar store bowls have the right number on the bottom, but they never have just lye in them, they have soap batter. Should I worry?


----------



## LilianNoir

Well my shopping trip today was a success! I found #5 pitchers (for making lye solution and batter) at the local dollar store - we have three and last time I only checked one. AND! This particular one was closing so I got stuff super cheap. and then I was able to get some of the #2 paint buckets for batter at Home Depot. I used the 2.5 qt paint bucket to make the swirl soap from my brambleberry kit today. 

^_^ 

That's a good point about calling (or emailing) Target. I think I'll do that tnoght. 

thanks again for the advice. I feel very much like a newbie and I'm always asking what are probably silly questions. But everyone here is always helpful and kind. Thank you.


----------



## dibbles

LilianNoir said:


> I feel very much like a newbie and I'm always asking what are probably silly questions. But everyone here is always helpful and kind. Thank you.


I'm glad you found what you needed, and on sale at the dollar store must have been quite a bargain. Never feel your questions are silly...we've all been there, or there are others that are there with you and wondering the same things. Happy soaping


----------



## DeeAnna

MGM said:


> My understanding was that it wasn't a good idea to mix LYE in glass or non HDPE plastic, but that soap batter is ok?...



I avoid glass containers for any aspect of my soap making. I definitely do not want to use a glass bowl with soap batter as a routine. Keep in mind, even if you dilute your lye solution with fat, it's still very alkaline, and glass is just not the wisest idea.

That said, I have used a pyrex bowl to make soap a few times -- specifically when I wanted to learn how soap emulsifies. I wanted to see how the soap batter looks from top to bottom and a glass bowl was the only way to do that. It's not going to be the kiss of death to use a glass bowl once in awhile for learning purposes. Just not the best idea for routine soap making.

If I was teaching a beginner soap making class, I'd make this rule black and white -- absolutely no glass for soap making.


----------



## Susie

I only use plastic or stainless steel.  You would have to ask yourself if the risk of breaking/shattering is worth it.  I value my eyes and other body parts, so to me the answer is no.  And since most of my bowls/containers are free or very cheap, then the cost of using them vs having to replace the Pyrex every so often becomes another "selling point" in favor of the plastic.  

The only SS pot I have gets used only with huge batches.  And I bought it to render tallow, so using it for soap is a "free" use.


----------



## SoapSisters

Susie said:


> I only use plastic or stainless steel.  You would have to ask yourself if the risk of breaking/shattering is worth it.  I value my eyes and other body parts, so to me the answer is no.  And since most of my bowls/containers are free or very cheap, then the cost of using them vs having to replace the Pyrex every so often becomes another "selling point" in favor of the plastic.
> 
> The only SS pot I have gets used only with huge batches.  And I bought it to render tallow, so using it for soap is a "free" use.


Would oven-safe ceramics be safe to soap in?


----------



## shunt2011

SoapSisters said:


> Would oven-safe ceramics be safe to soap in?


I wouldn't use ceramics for soaping.  Still glass and I'd be concerned with the finish.   I too only use plastic or stainless steel.


----------



## earlene

MGM said:


> My understanding was that it wasn't a good idea to mix LYE in glass or non HDPE plastic, but that soap batter is ok? I don't know if my dollar store bowls have the right number on the bottom, but they never have just lye in them, they have soap batter. Should I worry?




It doesn't have to be HDPE, it can be PP as well.  My recycle #5 plastics are PP, not HDPE.
For the types of plastics, refer to this article: https://learn.eartheasy.com/articles/plastics-by-the-numbers/

You will know when the the plastic you are using can't handle it.  A very long time ago, I used a cheap plastic mixing cup for lye solution and after a few times, it started to develop cracks in the bottom.  I am so glad I developed the habit of mixing my lye solution with the container seated inside my kitchen sink, because I actually had lye leak out from those cracks the last time I used that cup.  After than experience, I never bought those particular measuring cups again.  I am very careful about the plastics I mix my lye in, and my soap batter as well.

I also use some containers that have no recycle code on the bottom; they are either so old that recycle codes weren't being use yet, or they were made in China (that is stamped on the bottom) and for some reason (profit), stores in the US still sell new plastic items without a recycle code.  When it's time to throw them out, that means they will go into landfill instead of being recycled, which is a real shame.  But I suppose I didn't think of that when I purchased them, though.  Or maybe they were so inexpensive I chose to buy them anyway (Goodwill purchases, for example).  Now when purchasing plastic, though, if it doesn't have a recycle code stamped on it, I won't buy it because I don't want to introduce non-recyclable plastics into my home.

I also use stainless steel sometimes, but mostly plastic because it weighs less when I have to lift it full of lye or soap batter.


----------



## Arimara

I get having weak wrists/ hand issues. I also have some. I ordered a  stainless steel pitcher from Amazon, which was light enough for me to make soap with 16oz oils. I use that if I don't want to soap cooler.


----------



## MGM

DeeAnna said:


> If I was teaching a beginner soap making class, I'd make this rule black and white -- absolutely no glass for soap making.



Yes, sorry, I wasn't advocating for glass; the downsides seem to outweigh any upsides (weight, breakability, etching, etc. etc.). I meant for mixing lye: I know that it's important to have the right type of plastic container to bear the heat of the lye water, but I didn't think it was as crucial to have a batter pot that was made of HDPE plastic, since the oil + lye water are cooler. 
Does that make sense?


----------



## earlene

MGM said:


> Yes, sorry, I wasn't advocating for glass; the downsides seem to outweigh any upsides (weight, breakability, etching, etc. etc.). I meant for mixing lye: I know that it's important to have the right type of plastic container to bear the heat of the lye water, but I didn't think it was as crucial to have a batter pot that was made of HDPE plastic, since the oil + lye water are cooler.
> Does that make sense?



It does not have to be HDPE plastic, no.  PP is fine.

See this section from DeeAnna's classicbells site (link to entire article):


> *High density polyethylene and polypropylene are best.* Most people prefer containers made from high density polyethylene, HDPE, with a *#2 recycling code*, or polypropylene, PP, with a *#5 recycling code*. Containers with these codes have *excellent resistance* to lye up to the maximum 50% concentration. They are *heat resistant* enough to withstand the heat of a hot lye solution and are often *sturdy* enough to be a durable, safe container for lye.
Click to expand...


----------



## MGM

earlene said:


> It does not have to be HDPE plastic, no.  PP is fine.


Right. My *lye* container is PP5, but my *batter* container is....I have no idea. I didn't look cause I didn't think it was important because it doesn't get as hot.


----------



## jcandleattic

MGM said:


> Right. My *lye* container is PP5, but my *batter* container is....I have no idea. I didn't look cause I didn't think it was important because it doesn't get as hot.


Hot really isn't the issue - there is still unreacted lye in soap batter than can/will react to plastic that isn't rated for that particular chemical. If you have not had any issues, then yours must be the right type of rated plastic for caustic material.


----------



## DeeAnna

MGM said:


> ...I meant for mixing lye: I know that it's important to have the right type of plastic container to bear the heat of the lye water, but I didn't think it was as crucial to have a batter pot that was made of HDPE plastic, since the oil + lye water are cooler.
> Does that make sense?



I understand where you're coming from, and I was responding to your concern, but I realize I didn't explain myself well enough.

It isn't just the temperature that needs to be considered -- it's also the high pH. Soap batter is every bit as nasty alkaline as lye solution.

edit: I can see that I need to revise my article (the one Earlene linked to in her latest post) to broaden the language to include containers for soap batter as well as for lye solution.


----------



## szaza

Oh my, looks like I'll need to invest in stainless steel bowls for hpop.. thanks for starting this thread @LilianNoir !


----------



## MGM

Oh I'm glad we clarified, as I thought it was only the hot that was a problem. I will double-check the bottom of my vessel and perhaps invest in a second Dollar Store purchase


----------



## Mobjack Bay

I have had really good luck finding stainless steel bowls at the thrift store, but most of them are too big for the size of the recipes I’m making right now.  I didn’t pay more than $2-3 for them.  They’re deep batter bowls, not wide like salad bowls.  I looked and looked and looked for a pitcher and finally gave up and ordered one from Amazon. I also bought a bunch of silicone spatulas at the thrift store, but my favorites for soapmaking turn out to be long flexible icing spatulas that I ordered from Amazon (norpro, I think).


----------



## JasmineTea

I have multiple sizes of stainless steel measuring cups that I use for soapmaking and personal care making.  Here's a 2-qt one from Amazon: https://www.amazon.com/gp/aw/d/B010PJUD98?psc=1&ref=ppx_pop_mob_b_asin_title

I like these because they are not heavy, are not breakable, can be heated in a pot of hot water or direct heat, have a spout and handle, and are made of a thin enough metal that the pour spout is not thick and cumbersome to use.


----------



## Mobjack Bay

JasmineTea said:


> I have multiple sizes of stainless steel measuring cups that I use for soapmaking and personal care making.  Here's a 2-qt one from Amazon: https://www.amazon.com/gp/aw/d/B010PJUD98?psc=1&ref=ppx_pop_mob_b_asin_title
> 
> I like these because they are not heavy, are not breakable, can be heated in a pot of hot water or direct heat, have a spout and handle, and are made of a thin enough metal that the pour spout is not thick and cumbersome to use.



That’s exactly what I bought!


----------



## linne1gi

MGM said:


> Yes, sorry, I wasn't advocating for glass; the downsides seem to outweigh any upsides (weight, breakability, etching, etc. etc.). I meant for mixing lye: I know that it's important to have the right type of plastic container to bear the heat of the lye water, but I didn't think it was as crucial to have a batter pot that was made of HDPE plastic, since the oil + lye water are cooler.
> Does that make sense?


It’s not actually the heat of the lye water (although that does factor in somewhat), it’s the fact that the lye actually etches the glass. That’s why it’s a bad idea to use glass for any part of the soap making process. The soap batter still has active lye, even after trace, the lye is active and will etch the glass. Lye etches plastic as well, but plastic holds up better, maybe in 50 years or so the plastic will break!


----------



## earlene

linne1gi said:


> It’s not actually the heat of the lye water (although that does factor in somewhat), it’s the fact that the lye actually etches the glass. That’s why it’s a bad idea to use glass for any part of the soap making process. The soap batter still has active lye, even after trace, the lye is active and will etch the glass. Lye etches plastic as well, but plastic holds up better, maybe in 50 years or so the plastic will break!


Well, that depends on the plastic.  I've had low-grade plastic (not lye safe plastic) develop cracks that leaked lye out the bottom in only a very short time - probably a couple of months.  That was before I stated paying attention to the type of plastic I was using.  And of course, I always made sure to mix lye with the container seated inside my kitchen sink, so there was not problem with the spill.  I suspect it might have taken longer if that was the same plastic I used for mixing soap batter, but it was just for mixing lye.


----------



## Susie

So far, I've only had one spill from plastic failing me.  And it was not much, and easily transferred to another container.  Knock on wood.

Having that one, however, taught me to check the bowls and containers before using.  I just run cold water in it, and push with my fist.  If there is any leak or give to the plastic, in the trash it goes.  

It's never a failure if you learn something.


----------



## LilianNoir

szaza said:


> Oh my, looks like I'll need to invest in stainless steel bowls for hpop.. thanks for starting this thread @LilianNoir !


You're very welcome! I'm glad I did too, as it seems to have helped several people.
I'm a  little shy about asking "newbie" questions sometimes but as teacher I know well the old adage "someone else will have that question!" is quite true.


----------



## melinda48

earlene said:


> Well, that depends on the plastic.  I've had low-grade plastic (not lye safe plastic) develop cracks that leaked lye out the bottom in only a very short time - probably a couple of months.  That was before I stated paying attention to the type of plastic I was using.  And of course, I always made sure to mix lye with the container seated inside my kitchen sink, so there was not problem with the spill.  I suspect it might have taken longer if that was the same plastic I used for mixing soap batter, but it was just for mixing lye.


#5 plastic works great and is not expensive.


----------



## earlene

melinda48 said:


> #5 plastic works great and is not expensive.


True that it works great, which I have pointed out in previous posts, however I was responding to linne1gi's statement that plastic wouldn't break from lye in about 50 years.  I was pointing out that it depends on the type of plastic used.  

I use #2 and #5 plastic with no problems whatsoever, but the cheap plastics (cheaply made) will deteriorate quickly.  That was my point.


----------

