Does lye water become "safe" to handle after a few days?

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happilyabby

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I've seen where people sometimes set their soap making equipment aside for a few days...wait for it to turn into soap...and then do the cleanup. What about the container that was used to make your lye water? It's not going to turn into soap...so is it safe to handle after 24-48 hours?
 
No science knowledge behind this answer, but I'm going to say no.

The equipment becomes safe because the lye is being consumed in the saponification process. There is no such thing happening in the plain lye water. It's lye today and still will be whenever you come back to it.

I usually just rinse my lye containers out well in the sink (I'm not worried about this small amount of lye and my pipes - it's so small and the amount of water running with the rinse dilutes it even further) then wash them as normal.
 
Any lye residue isn't going to become more safe with time unless it's mixed with something to neutralize it (like oils). If anything, it will become more concentrated as water evaporates.

Lye is worthy of respect, but it's not radioactive napalm. Rinse well while still wearing your safety equipment. Add a bit of vinegar (after rinsing) to neutralize if it makes you feel better. Then wash with soap and water. Don't leave it sitting around unattended.
 
If you read through more threads, you will see references to master-batching. This is when people pre-mix their lye and water in large batches, and premix their oils in large batches. If lye water lost it's potency, this would not be possible. Respect the lye.
 
Thanks for the quick responses :)

This was only my second batch of soap and there is still A LOT for me to learn about cold process. For instance, on this batch...I mixed my lye water in a large glass measuring cup. Then I mixed my oils in a mixing bowl. Added my lye water to the oils. Got a thick trace and then (oh no!) poured it back into my lye water measuring cup for easy pouring. *Face palm* After pouring into my molds, I realized what I'd done. I'm going to guess this soap isn't safe to use seeing as there could be unsaponified (is that a word?) lye in it?
 
As the others have said, lye does not "become safer" with time unless there is something for it to react with. In ~small~ quantities such as tiny drops of lye or a thin film in a container, lye can react with things like CO2 in the air, given enough time. So in some situations, yes, lye can "become safer", but again only in the right circumstances and given enough time.

That said, if you DON'T KNOW, then DON'T ASSUME. Treat any lye residue, however large or small, as if it is just as reactive as when the lye was freshly made. The advise that has been given to use reasonable safety gear and rinse well with water is spot on correct.

ETA:

"...Got a thick trace and then (oh no!) poured it back into my lye water measuring cup for easy pouring. *Face palm* After pouring into my molds, I realized what I'd done. I'm going to guess this soap isn't safe to use seeing as there could be unsaponified (is that a word?) lye in it? ..."

Well, the soap batter you were messing with had a lot of unsaponified lye in it too. From what I gather, you poured soap batter that had a lot of strong lye in it into a measuring cup that contained a small residue of the lye solution. If that is the case, I don't get your concern.

Maybe there are some important facts missing -- for example, did you have a lot of lye solution in that measuring cup???

ETA2:

And you're going to get a lecture about mixing lye in a glass container. Use stainless steel or lye-safe plastic only!
 
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As long as you measured your oils and lye and water correctly, I think your soap should still be safe to use. If you emptied the measuring cup completely into your oils, there should have been very little residue in the cup. When you poured the oils back in, the oils were still unsaponified, and can still absorb any lye left in your cup. Saponification doesn't happen immediately. Once your soap has saponified, you can zap test it to be sure there it is okay.

As a side note, I have read to not use glass or pyrex to mix your lye water in as small etches can cause it to burst and break.
 
Thanks, guys. I'm learning a lot here. Didn't know glass was unsafe to use for lye. I will definitely take that into account for my next soap making adventure.

There was not a lot of lye solution left in the container. Only what would be left after pouring the entire contents out without scraping the sides. Hopefully my soap will make it :)

Just for reference, I was following this recipe: http://www.diynatural.com/how-to-make-soap-2/
 
"...There was not a lot of lye solution left in the container. Only what would be left after pouring the entire contents out without scraping the sides...."

I'd say you have nothing to worry about.

"...I was following this recipe: http://www.diynatural.com/how-to-make-soap-2/ ..."

now that we know what recipe you used ... this will trigger another round of advice. Here are several things that come to mind --

1. Do NOT measure by volume. Get a scale that weighs in grams and use it instead.

2. Never use someone else's recipe without running the recipe through a soap calculator. Always. Even the best of soapers make mistakes ... and bloggers aren't always right. A couple of good calcs -- http://soapee.com/calculator or http://www.soapcalc.net/calc/SoapCalcWP.asp

3. Never substitute one fat for another (I'm looking at the blogger's instruction to use "...⅔ cup other liquid oil – like almond oil, grapeseed, sunflower of safflower oil...") without running it through the soap calculator to confirm the amount of lye won't change. Sometimes it doesn't make a difference, but if YOU don't know that to be true, then it's far better to double check than take someone else's word for it -- point #2 applies here.

4. You don't need the soap to be at a pudding like trace, as the blogger instructs. It was an okay thing to do for a first batch, however. Just something to keep in mind for future batches.
 
That you so much for the advice and references, DeeAnna. I need to make myself more familiar with using a soap calculator.

Also, can you recommend a site for purchasing supplies? I'm in need of a good scale.
 
For scales, the most common recommendation seems to be for the KD7000 or KD8000. Mixing bowls and such can be bought at the dollar store or I like to use buckets from the hardware store - just make sure that anything you will mix lye in is HDPE plastic.
 
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A note of caution... please find a different container for mixing your lye solution. Glass can shatter without warning! Pick plastic with a 2 or 5 at the bottom or stainless steel containers for anything that will come into contact with lye. Not even Pyrex can be trusted.

I know you've probably seen folks in books and videos happily using glass who say they've never had a problem, but it simply isn't worth the risk.
 
I don't know of any one-stop shop for soaping supplies. Most of us hobby soapers might use several to a half dozen suppliers for fats, lye, fragrance, etc.

I have several "My Weigh" scales from oldwillknotscales.com and like them for soaping, but my opinion is definitely am not the last word on this topic! Best way to get a sense of what people like for a soaping scale is to look for posts on this topic. This will get you started: https://www.google.com/search?q=scales+buying+site:soapmakingforum.com
 
I also have a pretty good scale from walmart. I use it multiple times a week and I love that it has an 11 lb capacity. Thats pretty high and more than good enough for my 3/5 lb batches.

The specifications don't say what it weighs to but its:

min: 0.05 oz or 1 gram
max: ~11 lbs or 5 kg

I find it is quite accurate and it has been working on the same 4 batteries for 1.5 years. Its taken a couple of splashes of raw batter too so I'd say its pretty robust. I love that the top is glass so its easy to clean.

If you are weighing out something that weighs very, very little (<0.15 oz or <3 grams) you have to do it quickly otherwise the "floating zero" kicks on and it actually continually re-zeros. I've had this problem with some essential oils/powders. I felt like I kept weighing stuff out and it wasnt changing. You can also use something heavy (like a glass container instead of light plastic) to weigh into so that doesn't happen.

http://www.walmart.com/ip/Professional-Electronic-Kitchen-Scale/38241740
 
As far as clean up goes, I soap in the kitchen, so as soon as I add my lye to the oils, I place the stainless steel saucepan that I had the lye in, in the sink, and run water into it, to dilute any drops of lye that might remain, and after I finish soaping, I wash it. There's no reason I can see to wait to get that one cleaned. As for the soap pot, I scrape every last little bit that I can with my spatula into the mold. We pay a lot for our ingredients, and I hate to waste anything. What little residue is left, I wipe out with a paper towel, and discard. Then I wash that pot. As you continue soaping, you'll find your own routine that works best for you. I doubt that any two of us do it exactly the same way. Kind of like making spaghetti sauce. :grin:
 
..... I doubt that any two of us do it exactly the same way. Kind of like making spaghetti sauce. :grin:


You open the jar and pour out your soap? ;)

As others have said, rinse it through with water and then wash normally is my routine with lye containers. Lye is a drain cleaner, so it is not usually a bad thing unless you have a septic tank
 
a good lye calculator for beginners is at Brambleberry. I used that one when I began. It's accurate and no fuss. There are plenty of tutorials right here to search out to help you learn to use SoapCalc, which is more intense.

Start reading now about the acids in oils and the properties they bring to the table and learn what oils do what and why---for example-- what coconut oil brings to the table, it's pro's and cons, etc. (coconut oil is the most cleansing, but also the most drying, as a hint.) There is a lot of info right there to keep one busy for days to weeks, depending on how many oils they want to delve into!

Anyway, the 'why' behind doing this is to get a handle on 'why' we make soap-- to know how to make a soap that is more cleansing, more bubbly, bubbly yet good for the skin, cleansing yet not too stripping.....etc. As you find out about the acids (oleic, linoleic, etc.) you will find out more about this as well. Happy reading! (Reading all this mess will also, in turn, make you a little more confident.)

After all the advice given just right here, your third batch should be made in much more confidence! Congrats on your first two batches already though! Yay!!
 
Welcome, Happilyabby! :)

Just for reference, I was following this recipe: http://www.diynatural.com/how-to-make-soap-2/

Hmmm...I believe I've run across that recipe before here on the forum. If I recall correctly, a few of our beginners quite innocently used it as their first ever soap recipe and then came here with questions because they had some problems with it. lol

Ditto what everyone else has said. Wonderful advice. :thumbup:


IrishLass :)
 
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