Lye--how long can it sit?

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I do mine a bit differently. I mix mine in a 2-gallon HDPE bucket in the sink which is sitting in ice water because it does heat up considerably. While it is cooling I lightly cover with a cloth. At times I will get some lye that settles out of solution which I am sure is from evaporation but it has never affected my soap, and I just prefer to not put a lid on hot lye. I also like to mix in no larger than 2-gallon buckets that I can handle pouring out of into a Rubbermaid pitcher to transfer into my 1-gallon storage bottles. This is all done in my sink in case of spills.
 
Completely missed this portion. I have a RO filter that doesn't offer the DI filter with it and this is the water I use to make my MB lye, and I have never, ever had a problem with the water. (other things yes, but not the RO water! :) )
That is great because DI filters (good ones) are expensive. I used it for breeding fish. My jugs are what they call splash proof. Kind of like detergent jugs. I knew things could be made easier and now I can eliminate the prep time for the lye. I either use 30% or 33% most of the time, so I have enough jugs.

I do mine a bit differently. I mix mine in a 2-gallon HDPE bucket in the sink which is sitting in ice water because it does heat up considerably. While it is cooling I lightly cover with a cloth. At times I will get some lye that settles out of solution which I am sure is from evaporation but it has never affected my soap, and I just prefer to not put a lid on hot lye. I also like to mix in no larger than 2-gallon buckets that I can handle pouring out of into a Rubbermaid pitcher to transfer into my 1-gallon storage bottles. This is all done in my sink in case of spills.
I have a couple of oil recipes that I like and I am going to make a gallon of the two for use later. I have a old refrigerator in the garage that I can use to store the oils.
 
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That is great because DI filters (good ones) are expensive. I used it for breeding fish. My jugs are what they call splash proof. Kind of like detergent jugs. I knew things could be made easier and now I can eliminate the prep time for the lye. I either use 30% or 33% most of the time, so I have enough jugs.
If you make the solution in a 50/50 then you can make it to whatever concentration you want at time of soaping. I don't always use the same concentration depending on the soap I'm making so this makes it easier.

I just prefer to not put a lid on hot lye
My lid and wrap is just loosely set on top of it. I've done this for years now and have never had a problem. I wouldn't be comfortable securing the lid tightly on hot lye either.

This is all done in my sink in case of spills.
This is also how I do mine, but I don't try to pick it up and pour it. I use a ladle and funnel to get it into the jugs, until I can lift it and then pour it into the funneled container. I make/hold in one side of the sink, then when transferring, have the detergent jug in the other side of the sink.
 
Would you mind telling me what you do to make your master batch of lye. I have some 2 gallon chemical containers that I got from a fertilizer company (brand new never been used) and I think it would be worth making some ahead of time. I think I know what to do but confirmation would be better. Also I have an RO filter with a deionizer filter, would that make the water better or would it be ok with just running the water through the RO filter and bypassing the DI filter?


I make my 50% lye solution in a plastic PP #5 pitcher with lid, and when it has cooled down I store it in an airtight HDPE container which happenes to be a cleaned-out, reclaimed laundry detergent bottle with a no-drip spout and screwtop lid. As long as it is stored in a proper container and tightly covered, it lasts for a very long time. I'm talking much more than just months, but years.

The reason I like working from a 50% solution is because it's super easy to figure out the math that it takes to tailor it to use with any recipe no matter how big or small the batch, and no matter what % lye solution you choose to employ for your batch. To tailor it to whatever lye solution I choose to use, I just use this simple 2-part equation, which works across the board with every formula no matter what:

Here's how much 50% lye solution to weigh out for your batch: Multiply the total recipe amount of dry lye your formula calls for by 2. That will give you how much of the 50% lye solution you need to weigh out for your batch.

Here's how much extra water to weigh out for your batch: Subtract the total recipe amount of dry lye for your formula from the total recipe amount of liquid for your formula. That will give you how much more liquid you need to weigh out for your batch to compensate.

That's all it takes to figure it out. Easy-peasy. :)

Now, I do need to make mention that there is some slight evaporation that takes place when mixing the 50% solution. After my very first master-batch in which I made sure to weigh everything from beginning to end (container/cover and all), I figured out that my water loss from the heat reaction during mixing came to 6 grams worth, i.e., it weighed 6 grams less than it should have, so I just added 6 grams of water back in to compensate and all went well.

The size of my 50/50 masterbatch is a little over 4 lbs. worth, so as a result of my first experience, after having first weighed out my container and cover, I now weigh out 2 lbs 3.3 oz (or 1002 grams) of lye. And then I weigh out 2 lbs 3.6 oz (or 1008 grams) of water- a 6 grams excess. In the end, right when I get done mixing, I weigh my finished solution to see if it all adds up correctly (the weight should be 2004 grams if all went well). If it comes up short (which surprisingly has never happened yet with my subsequent masterbatches), I would just add more water at this time to equal 2004 grams, but so far, all has gone well and it weighs out 2004 grams - an even 1:1 ratio. When I go to weigh the solution later, after it has cooled off, it's still 2004 grams (I cover my container as soon as I'm done mixing).


IrishLass :)
 
I use some of my lye when my outside drain gets clogged with shower hair ( sorry that’s gross, I do try to stop it from getting in there!) and then rinse it through well after it’s sat for a while. Eats right through it, so guess you could do that as long as you know no kids/pets/anyone will go near it while it’s sitting. It’ll saponify any fats lurking down there and help break down the fat burgs! I just make sure it’s well washed through and the kitty is locked in
 
Perhaps the users who haven't posted in years can have their names removed so that they're not being quoted and it will save time from you having to post when they last posted?
 
I make my 50% lye solution in a plastic PP #5 pitcher with lid, and when it has cooled down I store it in an airtight HDPE container which happenes to be a cleaned-out, reclaimed laundry detergent bottle with a no-drip spout and screwtop lid. As long as it is stored in a proper container and tightly covered, it lasts for a very long time. I'm talking much more than just months, but years.

The reason I like working from a 50% solution is because it's super easy to figure out the math that it takes to tailor it to use with any recipe no matter how big or small the batch, and no matter what % lye solution you choose to employ for your batch. To tailor it to whatever lye solution I choose to use, I just use this simple 2-part equation, which works across the board with every formula no matter what:

Here's how much 50% lye solution to weigh out for your batch: Multiply the total recipe amount of dry lye your formula calls for by 2. That will give you how much of the 50% lye solution you need to weigh out for your batch.

Here's how much extra water to weigh out for your batch: Subtract the total recipe amount of dry lye for your formula from the total recipe amount of liquid for your formula. That will give you how much more liquid you need to weigh out for your batch to compensate.

That's all it takes to figure it out. Easy-peasy. :)

Now, I do need to make mention that there is some slight evaporation that takes place when mixing the 50% solution. After my very first master-batch in which I made sure to weigh everything from beginning to end (container/cover and all), I figured out that my water loss from the heat reaction during mixing came to 6 grams worth, i.e., it weighed 6 grams less than it should have, so I just added 6 grams of water back in to compensate and all went well.

The size of my 50/50 masterbatch is a little over 4 lbs. worth, so as a result of my first experience, after having first weighed out my container and cover, I now weigh out 2 lbs 3.3 oz (or 1002 grams) of lye. And then I weigh out 2 lbs 3.6 oz (or 1008 grams) of water- a 6 grams excess. In the end, right when I get done mixing, I weigh my finished solution to see if it all adds up correctly (the weight should be 2004 grams if all went well). If it comes up short (which surprisingly has never happened yet with my subsequent masterbatches), I would just add more water at this time to equal 2004 grams, but so far, all has gone well and it weighs out 2004 grams - an even 1:1 ratio. When I go to weigh the solution later, after it has cooled off, it's still 2004 grams (I cover my container as soon as I'm done mixing).


IrishLass :)

Would a jerry can (brand new) be equally suitable to use? The reason I’m asking is ravise I have Issues with my left arm and can not lift a container that heavy. The jerry cans come in all sizes.
 
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Would a jerry can (brand new) be equally suitable to use? The reason I’m asking is ravise I have Issues with my left arm and can not lift a container that heavy. The jerry cans come in all sizes.


Hi Claudette! As long as the jerry can is made of HDPE plastic (and it looks like they are), you'll be fine!



IrishLass :)
 
I use 50% NaOH solution at room temperature. If I want the soap batter to be warmer, I heat the fats rather than the lye solution for safety's sake.

If you've been taught the myth that the temps of the lye solution and fats must be within 10 degrees, you can toss that out the window. It's the batter temp that's important for the outcome of your soap making.

It's certainly easy to understand if the lye solution and the fats are about the same temp, say 100 F, then the soap batter will be about 100 F as well. But that's the only advantage to matching the temps of the lye and fat.

As far as the chemistry is concerned, your lye solution could be 70F and your fats could be 110F, but if the soap batter is 100F when the two parts are mixed, that's the only temp that really matters.

The only caveat about the temperature of a masterbatched 50% lye solution -- This solution must be kept above 60F / 20C while in storage. If the solution cools into the middle 50s F, some of the NaOH will crystallize out and form a glass-like sheet of solid NaOH on the bottom of the container.

You must get the solid NaOH fully dissolved before the solution can be used, which takes a fair bit of work and patience. It is much easier to avoid the problem than to have to fix it.
 
I gave it a try as I think it could save quite abit of time. I left my usual quantity lye solution out overnight. In the morning it was a little gloopy which I didn't expect. Can anyone tell me if this is normal please.
 
I have no idea how to answer your question without any real details.

What was the lye concentration? Was the solution in a container that was open to the air or was it in a closed container? What temperature was the lye solution while it sat overnight? What do you mean by gloopy -- can you explain in concrete words what you are seeing?
 
I know it's a bit late, but I've had my lye solution dip to 70 F before - going by the myth that everything needed to be within 10 degrees of each other - I would re warm my lye water solution and oils. I have an old sock full of rice that I microwave and sandwich between my container of oils and container of lye solution. Brings it up to about our just under 80 F. I probably won't do that any longer, but it seemed like a much safer way to warm it back up - I read about others putting it in a microwave and that freaked me out!!
 
I master batch...33% Lye Solution. I make not quite 2 gallons at a time and then store it in the back of my soap cart. Since I master batch my oils/butters too (640 oz in a 5-gal bucket), I just reheat my oil (after a good stir with a commercial paint stirrer) 20-40 second PPP and then add my Lye Solution out of the jug. The Lye Solution temp is cool, but not cold.
 
You folks are awesome! I just posted on what containers should I use to hold my lye solution and here is the answer Except, would empty cleaned out bleach bottles work as well? (I make my own powdered detergent) I also have a RO filter and that also answered my question I hadn't even asked yet! Thank you so much!
 
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