# Trying to understood Lye water master batching



## Cal43 (Feb 28, 2019)

ok here I go...

50/50 measured  and mixed

*An example of how to add extra water for recipe 
Now my recipe at 33% of water as the percentage

Water weight is : 10.56oz
Lye 4.41 oz

Multiply lye by 2/ 4.41x 2=8.82 oz

Now I pour out 8.82 oz of 50/50 water solution

*Next calculate extra water needed:

Recipe water amount is 10.56 oz
Subtract lye amount from water amount on recipe / 10.56 oz- 4.41 oz = 6.15 oz

6.15 oz = the extra amount of water needed 

So... 50/50 lye water solution that was poured out was 8.82 oz+ 6.15 oz extra weather for particular recipe. 

Tell me,  is this correct??!!


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## Clarice (Feb 28, 2019)

I master batch at a 1:1 water:lye ratio and then use the SoapMakingFriend calculator to tell me the additional liquid needed.  

here is the link

https://www.soapmakingfriend.com/soap-making-recipe-builder-lye-calculator/

also great discussion in a recent thread that will tell you a lot you need to know.

https://www.soapmakingforum.com/threads/lye-solution-master-batch.18098/

really good information

I understand the principles behind the math - but have not done it given the fabulous recipe builder!


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## The Efficacious Gentleman (Mar 1, 2019)

But yes, you are correct. 

Required lye X 2 is the amount of 50/50 you use. 

Required water - half of the 50/50 amount (or the required lye amount, they're the same number and it saves a maths step) is the amount of extra water to put in. 

Heads up in case you haven't heard about it ... The master batched mixture will warm up when you add water in to it.


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## SoaperForLife (Mar 1, 2019)

At the risk of sounding like an idiot, why do people master batch lye?


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## The Efficacious Gentleman (Mar 1, 2019)

If you like to soap at room temperature, it means that you don't have to wait as long for the lye water to cool. 

It can also generally save time if you make lye once for a few batches l, you just have to melt the oils and you're pretty much good to go


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## Cal43 (Mar 1, 2019)

The Efficacious Gentleman said:


> But yes, you are correct.
> 
> Required lye X 2 is the amount of 50/50 you use.
> 
> ...



Oh good to know. Around what temperature does it usually go to?


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## The Efficacious Gentleman (Mar 1, 2019)

Not as hot as when you first make it, but still quite warm. I would use the same quality container that I would use if I were making fresh lye solutions


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## shunt2011 (Mar 1, 2019)

SoaperForLife said:


> At the risk of sounding like an idiot, why do people master batch lye?



It allows me to have a batch of lye ready to go.  It's mixed and cooled.   I generally mix 4 lbs lye and 4 lbs water add my silk and let it cool.  I don't have to wait for my lye to cool down.

I add my extra needed liquid (milks/beer etc)  to my oils not to my lye mixture.


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## Clarice (Mar 1, 2019)

Maybe because I make small batches (still trying to find my perfect recipe) i do not find much heating up with my master batch when i add water.

Yesterday I mixed full cream with my master batch (again, small batch - 8 oz) and the temp barely bumped.  Cream was cold.  I did, however, make the mistake of letting it sit for a bit, and I had sort of lye-glue.  I rescued with a stir - but it was still thicker than I would like.  lesson learned - stir cream in gently and use immediately!

This may be very different for larger batches - I only needed something along the lines of 1.6oz additional liquid and 2.4 oz master batch


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## DeeAnna (Mar 1, 2019)

Why do I masterbatch? Cuz in the long run, the masterbatch makes my soaping easier and safer and more pleasant.

I don't have to deal with dry NaOH nearly as often with all the safety issues of dealing with the fumes and triple checking that all the NaOH is dissolved and all that hassle. I mean ... whether you make lye solution for 1 batch or for 10, the hazards are exactly the same, so why do I want to do this 10 times rather than just one?

In addition I don't have to wait for hot lye to cool to a reasonable temp for CP soap. Even if the recipe uses extra water-based liquid, adding that to the soap batter doesn't heat the batter enough to be a concern.


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## Cal43 (Mar 1, 2019)

Clarice said:


> I master batch at a 1:1 water:lye ratio and then use the SoapMakingFriend calculator to tell me the additional liquid needed.
> 
> here is the link
> 
> ...


Yes I printed some of the information from that thread. I was just checking to see I I got before going forward. I going to check it out in there calculator also.


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## cmzaha (Mar 1, 2019)

Same as everyone else, I have no patience to wait for lye to cool so I master batch 50/50 which is easier math for me.


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## Clarice (Mar 1, 2019)

And Carolyn I think you made point about decanting master batch into smaller containers for easy pours?  Super idea.  I went to store and got $1.49 3/4 gallon soap with nice pour spout and I use that for working and keep bigger bottles for refilling the little one.  Easier on my hands


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## jcandleattic (Mar 1, 2019)

SoaperForLife said:


> At the risk of sounding like an idiot, why do people master batch lye?


It is a HUGE time saver and there is no waiting around for your solution to cool down to soap. 

I also masterbatch my main 3 recipes, so from time I start soaping to putting the soap in the corner to do it's thing, a batch for me can take as little as 6 minutes per or to up to 10-12 minutes depending on the intricacy. 

In one day if I am super ambitious, and have everything organized, I can make up to 7 batches of soap in less than 2 hours.  That frees up pretty much the rest of my weekend for me. (I only soap on weekends as I have a ft job outside the home)


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## DWinMadison (Mar 1, 2019)

SoaperForLife said:


> At the risk of sounding like an idiot, why do people master batch lye?


I just started master batching both lye and oils.  It makes the process go so much smoother and gets you to the fun part faster.  I'm not constantly waiting on my lye to cool and trying to make sure the lye water and oil are at similar temps before combining.  It also helps with clean-up.  I can't believe I waited so long to try it.

On master-batching lye....  I'm thinking it's like a sourdough starter.  So long as I add equal amounts (by weight, of course) of new lye and water to my existing master batch and give it time to  react, I'm still good to go, right?



Clarice said:


> And Carolyn I think you made point about decanting master batch into smaller containers for easy pours?  Super idea.  I went to store and got $1.49 3/4 gallon soap with nice pour spout and I use that for working and keep bigger bottles for refilling the little one.  Easier on my hands


I though about parsing out my lye like a did my oils, but I got nervous having a bunch of little lethal jars floating around.  I like keeping it in one container labeled as Lye/Danger!/Poison!/Don't Touch!! until needed then pour out just what I need.  Just my 2 cents.


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## jcandleattic (Mar 1, 2019)

DWinMadison said:


> I though about parsing out my lye like a did my oils, but I got nervous having a bunch of little lethal jars floating around.  I like keeping it in one container labeled as Lye/Danger!/Poison!/Don't Touch!! until needed then pour out just what I need.  Just my 2 cents.


I make 24 lb master batch lye solution (12lbs lye/12lbs water) and that sucker is heavy to lift for my old shoulders.

I keep the master masterbatched lye in a large liquid detergent bottle and then I have 3 smaller of the same type of bottle I use to fill from my master masterbached lye. Much easier to manage for me. I fill the 3 at the same time I make the master batch then the big bottle isn't as heavy to lift to refill the others.

I hope that makes sense.


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## DWinMadison (Mar 1, 2019)

jcandleattic said:


> I make 24 lb master batch lye solution (12lbs lye/12lbs water) and that sucker is heavy to lift for my old shoulders.
> 
> I keep the master masterbatched lye in a large liquid detergent bottle and then I have 3 smaller of the same type of bottle I use to fill from my master masterbached lye. Much easier to manage for me. I fill the 3 at the same time I make the master batch than the big bottle isn't as heavy to lift to refill the others.
> 
> I hope that makes sense.


Total sense.  I was just scared to do it because I'm basically a control freak.  I don't even like keeping a full single large container around.  See my comment below that one.  Thinking my best solution may be to just add equal measures of water and lye to replenish my master batch as it is used down...still keeping it all in a single container.  Unless somebody tells me that "feeding" a master batch is a bad idea.


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## IrishLass (Mar 1, 2019)

SoaperForLife said:


> At the risk of sounding like an idiot, why do people master batch lye?



LOL- no worries- I used to wonder the same thing. I kept seeing the term bandied about back in the day, but never really looked into it until the day my eye caught a little snippet of info about how with masterbatching, one did not have to make fresh lye solution for every single batch.......and that with 50/50 master-batching the math was super easy to do in order to adjust it to any batch no matter what my lye concentration. Being that making lye solution is my _least_ favorite thing to do with soapmaking, and knowing that the math to adjust for different lye concentrations would be easy, I jumped right on that bandwagon faster than you can say boo! It's so nice to be able to make several batches without having to don my extra super safety lye mixing gear _every single doggone time _I wanted to make a batch of soap. It's also nice that the lye solution stays good for a very loooooong time....years (if stored properly).




DWinMadison said:


> Total sense.  I was just scared to do it because I'm basically a control freak.  I don't even like keeping a full single large container around.  See my comment below that one.  Thinking my best solution may be to just add equal measures of water and lye to replenish my master batch as it is used down...still keeping it all in a single container.  Unless somebody tells me that "feeding" a master batch is a bad idea.




I've never fed a lye master-batch (I normally have 2 containers going), but as long as you keep track of its weight before and after each time you use it, and the weight matches up with what it weighed after the last time you used it, I personally don't see there being a problem with feeding it.
_
_
IrishLass


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## penelopejane (Mar 1, 2019)

I soap warm but still masterbatch my lye. I reheat it a bit before I use it.

I was resistant at first because I thought the maths might be daunting but you only have to do it once for each recipe check it three or four times and you have it forever. Well, at least until you tweak your recipe!


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## Steven (Apr 25, 2019)

The Efficacious Gentleman said:


> Required water - half of the 50/50 amount (or the required lye amount, they're the same number and it saves a maths step) is the amount of extra water to put in.



I've read this a few times and I'm having trouble getting my head around it. In the OPs example the batched lye solution is 8.82oz and the additional water is 6.15oz. What it sounds like you @The Efficacious Gentleman are saying is that half of 8.82oz is the amount of additional water to be added which would be 4.41oz, not 6.15oz. Which in my limited understanding would be a different lye concentration that the originally intended 33%, correct? Am I missing something obvious?


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## IrishLass (Apr 25, 2019)

Steven said:


> I've read this a few times and I'm having trouble getting my head around it. In the OPs example the batched lye solution is 8.82oz and the additional water is 6.15oz. What it sounds like you @The Efficacious Gentleman are saying is that half of 8.82oz is the amount of additional water to be added which would be 4.41oz, not 6.15oz. Which in my limited understanding would be a different lye concentration that the originally intended 33%, correct? Am I missing something obvious?



Hi Steven-  what The Efficacious Gentleman wrote in his post does not make sense to me either. The correct amount to add to the OP's recipe is indeed 6.15 oz, not the 4.41 oz The Efficacious Gentleman's post seems to be saying. I'm not sure why he said that.


IrishLass


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## LilianNoir (Apr 25, 2019)

Steven said:


> that half of 8.82oz is the amount of additional water to be added


No, that's not quite it.  The amount of water added is however much the original amount calls for MINUS half of the amount of 1:1 solution added. Because half of that solution is lye and half is water.

So, as another example.

I had a recipe that called for 8.0 oz water, 4.2 oz lye.

To use my 1:1 lye solution(so half lye, half water), I take a look at the amount of lye required and double it: 4.2x2 = 8.4. So I know that I need to measure out 8.4oz of lye solution in order to meet 4.2oz lye. 

With 8.4oz of solution, just as there is half (4.2oz) of lye, so there is water. 

I know that my 8.4oz of solution gives me 4.2 oz of water. So to determine how much more water to add, I take the original amount called for: 8.0 oz and subtract the amount of water i know is present in my solution - 4.2

8.0-4.2= 3.8. I need to add 3.8oz to meet the water requirement of 8.0 oz.

So to summarize: I double the amount of lye required to know how much solution to use. 8.4oz of 1:1 lye solution. Then subtract the original amount of lye called for(or, half the amount of solution) from the original water requirement to determine how much extra water/liquid.
8.4oz of solution, and 3.8 oz of water.

You can also check your math by adding together the originally called for amounts of lye and water (8.0 + 4.2 = 12.2) and then add together your calculated amounts of lye solution and additional water (8.4 +3.8=12.2)

Does that help at all (or did i make it worse? )

I think I see the problem.

@The Efficacious Gentleman wrote 





> Required water - half of the 50/50 amount



Which I think is being misinterpreted as "Required water EQUALS half of the 50/50 amount", but what is written and meant is "Required(by the recipe) water MINUS half of the 50/50 solution amount." to get the amount of added water.


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## IrishLass (Apr 25, 2019)

You hit it right on the nose, LilianNoir. I completely misinterpreted what Effy said.

@Steven - ditto what Lilian Noir said. 


IrishLass


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## Steven (Apr 25, 2019)

@LilianNoir  your explanation is in line with the math I was doing. Thank you for the clear step by step outline! I see your second post and I think that helps. It still took me a minute, but I think I got it after a couple reads.

@IrishLass thanks!


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## LilianNoir (Apr 25, 2019)

Steven said:


> @LilianNoir  your explanation is in line with the math I was doing. Thank you for the clear step by step outline! I see your second post and I think that helps. It still took me a minute, but I think I got it after a couple reads.
> 
> @IrishLass thanks!


You're very welcome! I used to teach math, so I hoped those skills were still around!


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## madison (Apr 25, 2019)

When using the dual-lye, how you do the calculation when you master batch the lye?


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## earlene (Apr 25, 2019)

madison said:


> When using the dual-lye, how you do the calculation when you master batch the lye?




When I do dual lye soaps, since I only masterbatch the NaOH, I just use the extra water to mix with the KOH.

Most of my dual lye batches are 95% NaOH and 5% KOH, so the extra water needed to make up the difference of water needed for the recipe is usually sufficient for mixing the KOH.

Example:

Say my Recipe calls for the following: 

137.1 grams water
 62.4 grams NaOH
 5.1 grams KOH


137.1 + 62.4 = 199.5  (total water plus NaOH)

199.5 - (62.4 x 2 = 124.8) = 74.7    (The 62.4 x 2 is to calculate how much of my MB lye I need.)

or 137.1 - 62.4 = 74.7   (This is to double check my math, a step I left out when I originally posted the calculations.

This means I need 74.7 grams additional water, which I use to mix with my 5.1 grams of KOH.


The above example is based on a [33% Lye] Concentration.

Edited to correct my math, which was off.  SO sorry for my errors - I must have been too tired for math!


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## madison (Apr 25, 2019)

earlene said:


> When I do dual lye soaps, since I only masterbatch the NaOH, I just use the extra water to mix with the KOH.
> 
> Most of my dual lye batches are 95% NaOH and 5% KOH, so the extra water needed to make up the difference of water needed for the recipe is usually sufficient for mixing the KOH.
> 
> ...



Thank you earlene. 
 How do you calculate the chelator? I would like to know how to do it with both citric acid and EDTA, if possible.


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## earlene (Apr 26, 2019)

I use a combination of EDTA with ROE since together they help prevent DOS, and the EDTA reduces soap scum exceptionally well.  The calculations are fairly easy with EDTA.  DeeAnna has put together instructional material on the use of EDTA at her site, classicbells.  Here is the link for EDTA: https://classicbells.com/soap/EDTA.html

Because I have plenty of EDTA, I have had no need to use citric acid as a chelator, but the calculations can be found here.


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## madison (Apr 26, 2019)

earlene said:


> I use a combination of EDTA with ROE since together they help prevent DOS, and the EDTA reduces soap scum exceptionally well.  The calculations are fairly easy with EDTA.  DeeAnna has put together instructional material on the use of EDTA at her site, classicbells.  Here is the link for EDTA: https://classicbells.com/soap/EDTA.html
> 
> Because I have plenty of EDTA, I have had no need to use citric acid as a chelator, but the calculations can be found here.



 When do you add EDTA and how to calculate with the master batch of lye?
I am not as fluent in calculating EDTA, but still like to master using it. I have some of my friends and family members still prefer citric acid over EDTA, I do well with citric acid. My question is when to add citric acid in lye master batch?


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## earlene (Apr 26, 2019)

Personally, I wouldn't add the chelator to the masterbatch lye, particularly if some of your soap is going to be made with one chelator, while other soap is made with another chelator.   I prefer to keep the lye as purely lye until it is time to use it in soap.  With any added material in the masterbatch lye solution, it would alter the measurements when you go to weigh out the amount needed for each batch of soap.

I masterbatch my lye and only use as much as I need for each soap I am making.  Normally I don't add anything to the lye before mixing it into the soap unless I want to melt some silk into it.

I masterbatch my 50% EDTA solution and keep it in a plastic bottle, then add the amount needed to each batch.  I don't actually add it to the lye at all.  Usually I add it with the oils or with the fragrance.  

I use 0.5% EDTA in my soap, so for a total batch size of 500 grams, that is 2.5 grams of my 50% EDTA solution.  The calculations are really made pretty easy when using the 50% solution.


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## madison (Apr 26, 2019)

earlene said:


> Personally, I wouldn't add the chelator to the masterbatch lye, particularly if some of your soap is going to be made with one chelator, while other soap is made with another chelator.   I prefer to keep the lye as purely lye until it is time to use it in soap.  With any added material in the masterbatch lye solution, it would alter the measurements when you go to weigh out the amount needed for each batch of soap.
> 
> I masterbatch my lye and only use as much as I need for each soap I am making.  Normally I don't add anything to the lye before mixing it into the soap unless I want to melt some silk into it.
> 
> ...



Thank you earlene.


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## atiz (Apr 26, 2019)

earlene said:


> When I do dual lye soaps, since I only masterbatch the NaOH, I just use the extra water to mix with the KOH.
> 
> Example:
> 
> ...



I have been following this thread because found it interesting. But I'm not sure I understand the example. If you need 62.4 g NaOH, isn't it the case that your [50%] master batch lye will have 62.4 g NaOH + 62.4g water in it? If so, the additional water needed is not 12.3 but (137.1 - 62.4) = 74.7 g.

I think I understand the rest.


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## madison (Apr 26, 2019)

atiz said:


> I have been following this thread because found it interesting. But I'm not sure I understand the example. If you need 62.4 g NaOH, isn't it the case that your [50%] master batch lye will have 62.4 g NaOH + 62.4g water in it? If so, the additional water needed is not 12.3 but (137.1 - 62.4) = 74.7 g.
> 
> I think I understand the rest.


I think you made a mistake with the last part, the 12.3 is the final amount of water needed for a batch of 33% lye solution.
(62.4 x 2 = 124.8) is for an equal amount of lye and water.


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## atiz (Apr 26, 2019)

madison said:


> I think you made a mistake with the last part, the 12.3 is the final amount of water needed for a batch of 33% lye solution.
> (62.4 x 2 = 124.8) is for an equal amount of lye and water.


Equal amount of lye and water = 62.4 lye + 62.4 water. 
According to Earlene's example recipe, you need 137.1 g water total. So with your "equal amount of lye and water" (from the masterbatch) you have taken care of 62.4 g water out of this 137.1 g. Which means you still have to add 74.7 g. 
At least this is how I would calculate it.


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## earlene (Apr 26, 2019)

atiz said:


> I have been following this thread because found it interesting. But I'm not sure I understand the example. If you need 62.4 g NaOH, isn't it the case that your [50%] master batch lye will have 62.4 g NaOH + 62.4g water in it? If so, the additional water needed is not 12.3 but (137.1 - 62.4) = 74.7 g.
> 
> I think I understand the rest.



Yes, you are correct, I guess I was too tired for math last night.  I will adjust my above post to correct it!  Thank you so much for pointing that out!


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## earlene (Apr 26, 2019)

madison said:


> I think you made a mistake with the last part, the 12.3 is the final amount of water needed for a batch of 33% lye solution.
> (62.4 x 2 = 124.8) is for an equal amount of lye and water.




No, *atiz* was correct.  My math was off, either because I was too tired to check my own work, or just too tired.  Anyway, I have corrected my original post to reflect the proper math. And the double checking method I normally use to check my math.  So I hope you haven't yet made any soap with the wrong calculations!


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## atiz (Apr 26, 2019)

earlene said:


> Yes, you are correct, I guess I was too tired for math last night.  I will adjust my above post to correct it!  Thank you so much for pointing that out!


Oh okay, thanks -- and sorry, it wasn't meant as a correction really, I just wanted to make sure I understand this masterbatch thing (since I don't make that much soap I don't actually masterbatch, although have done the "split method" when adding other additives to water).


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## earlene (Apr 26, 2019)

Oh, no problem whatsoever, *atiz.*  I certainly don't want any mistakes I make to sit here on the site uncorrected!  That would be horribly embarrassing, as well as possibly creating future confusion.  So I am truly grateful it was caught and I was able to edit the post to fix the original post with the error.  We are all fallible, after all, right?


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## Susie (Apr 26, 2019)

DW, I know I am late to the party, but no one has responded to you on whether you can "feed your masterbatch" or not.  I don't, just because it can continue to absorb moisture inside the plastic jug.  Mine, unless I store them in the Super Dry Storage Buckets (SDSB) with the Damp Rid and the Gamma Lid, routinely increase in weight between uses.  And I live in DFW with a much lower relative humidity than the Jackson metro area.  So I know yours is sucking up moisture also.  Hence the SDSB.  I have old NaOH 32 oz containers from ED that I store my masterbatch in, and I wait until I am on the last one before making more.

I masterbatch my KOH/NaOH blend at the same time.  Why not?  You know how much you need per batch.


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## madison (Apr 26, 2019)

Susie said:


> I masterbatch my KOH/NaOH blend at the same time.  Why not?  You know how much you need per batch.



Susie, how you do that please?



earlene said:


> No, madison was correct.  My math was off, either because I was too tired to check my own work, or just too tired.  Anyway, I have corrected my original post to reflect the proper math. And the double checking method I normally use to check my math.  So I hope you haven't yet made any soap with the wrong calculations!



 I am now confused, which one is the right one?


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## earlene (Apr 26, 2019)

madison said:


> I am now confused, which one is the right one?



Sorry, I meant *atiz* was correct.  SORRY again.  I did not mean to confuse you!


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## madison (Apr 26, 2019)

atiz said:


> Equal amount of lye and water = 62.4 lye + 62.4 water.
> According to Earlene's example recipe, you need 137.1 g water total. So with your "equal amount of lye and water" (from the masterbatch) you have taken care of 62.4 g water out of this 137.1 g. Which means you still have to add 74.7 g.
> At least this is how I would calculate it.


atiz, you were right, I was mistaken, I just got it, sorry about that.
Thank you for being around.



earlene said:


> Sorry, I meant *atiz* was correct.  SORRY again.  I did not mean to confuse you!


No worries earlene. thank you.  You explained  the idea in general, I got it but didn't follow the exact math, I was very exhausted today. Thanks to atiz for chiming in.


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## earlene (Apr 27, 2019)

madison said:


> No worries earlene. thank you.  You explained  the idea in general, I got it but didn't follow the exact math, I was very exhausted today. Thanks to atiz for chiming in.



Well, the cool thing is that if you use the Soapmaking Friend calculator here at SMF (still under development, but working pretty well, it seems), you can plug the masterbatch lye into it and come up with the correct numbers without having to do all the calculations yourself.  

I tried it out a bit ago with the masterbatch function and it does work.  I had some trouble figuring out how to enter the MB lye as there are no instructions attached (that I could find), but by choosing 1:1 as the water to lye ration (actually that should have been pretty easy to figure out, but for some reason I thought I would need to put in 50%, but that wasn't an option) it works out perfectly.

Even so, learning the math first is really a good thing to know how to do.  Then having something like all these great folks here at SMF to help double check our process (math included) is really helpful.  The day may come when a lye calculator isn't available and we want to make soap.


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## Susie (Apr 27, 2019)

OK, I am not the maths wiz at all.  Y'all's calculations above made my head hurt.  

Having said that, I know that I can get about 6 batches of soap from 32 oz NaOH, so I take the amount of NaOH I use per batch, 5.27 oz x 6 = 31.62 oz
I just repeat that simple equation for the KOH- 0.43 oz x 6 = 2.58 oz.  
Add those together for the amount of water to add 31.62 + 2.58 = 34.2 oz water.  
Add both alkali together, add slowly to water.  Allow to cool.  Pour into bottles.  Label appropriately. Easy Peasy.


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## Deborah Long (Apr 28, 2019)

So, now that I'm convinced that I *can* masterbatch - what can I store it in?  I bought a 1 gallon pitcher yesterday, made of PP #5.  Will that be okay?  The DH is worried that it's not HDPE...


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## earlene (Apr 28, 2019)

If the recycle code is #2 or #5 in the triangle, it is fine for storing your lye.  But it needs to have a tight fitting lid.  Does the lid screw on?  If so and it meets the #2 o #5 criteria, it will be fine.  By PP, is that Polypropylene?  If so, it should be #5 recycle and YES, that is lye safe.

See this thread:  https://www.soapmakingforum.com/threads/best-plastics-for-containing-lye-solution.61201/


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## Deborah Long (Apr 28, 2019)

@earlene - Yes!  Yay!  I'm on to masterbatching!  Thank you, everyone - especially @atiz for helping me understand it so thoroughly!


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## maxine289 (Apr 29, 2019)

Why is it important to have a tight fitting lid on the storage container?  Is it to prevent evaporation?  If there is evaporation, do you just weigh and then add the water that's lost?


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## DeeAnna (Apr 29, 2019)

No -- masterbatched NaOH won't evaporate; it will absorb water and you don't want that. Also exposure to air will reduce the purity of the NaOH because it reacts with carbon dioxide in the air.

In addition, you want to be safe and minimize the chance for spills or leaks. A screw-on lid is safest -- a snap on lid is not as good.

edit: Never fasten a lid on tight while the lye solution is still hot. You don't want pressure to build up in the container. Just put the lid or cap on the container but leave it loose until the solution cools. Then cap the container tightly.


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## earlene (Apr 29, 2019)

Even though I don't have children in my home, I prefer to use a bottle with a child-safe lid.  With the bottles I use, I know that if I knock over my bottle of lye it will not leak.  I know this to be the case because #1, I have tested it, and #2, I have actually knocked a bottle over once or twice.  Once, just a couple of days ago, in fact.  (safely in my sink, but still it did not leak)

You also need to label it as lye and poisonous.

What I use for storage of my master batch lye is the bottles that Essential Depot's lye comes in because:
1.  they are made of HDPE plastic, 
2.  they have child proof caps,
3.  they are already labeled appropriately for the contents*, and
4.  they are the perfect size for my hands and not too heavy for me to lift and pour when full.

* But I still add additional labeling information to include the following:
Masterbatch 50% Lye Concentration
date made
amount in solution (which I change as I use it) - because I like to keep tract of how much I have left 
On the bottom of the container I have the weight of the container, so I can deduct that from the weight of the bottle as I do my calculations.  
I use masking tape and a Permanent Marker to add the additional labeling information on the bottles and when I make new batches, remove the old tape, wash out the bottle with plain water and allow to dry before re-filling with new lye solution.

For safety I still keep my masterbatch lye bottles inside another lye-safe plastic bucket just in case something unforeseen happens and to ensure that I have a doubly safe method of transporting it from my storage area to my soaping area.  Granted, for me that is only about a 6 meters away from my kitchen sink, but it makes me feel that I am being as safe as possible.


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## DeeAnna (Apr 29, 2019)

_"...For safety I still keep my masterbatch lye bottles inside another lye-safe plastic bucket..."_

Good point, @earlene. I do this for my dry NaOH and KOH as well as lye solution. I have personal experience with a leaky NaOH container to know this "belt and suspenders" method is a wise idea.


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## penelopejane (Apr 29, 2019)

Deborah Long said:


> So, now that I'm convinced that I *can* masterbatch - what can I store it in?  I bought a 1 gallon pitcher yesterday, made of PP #5.  Will that be okay?  The DH is worried that it's not HDPE...


I use old liquid laundry detergent bottles with a 5 on the bottom. I soak the labels off and make my own labels so no one gets confused. I store them in a cupboard which is easily childproofed should l ever be in the lucky position of needing that facility.


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## Deborah Long (Apr 29, 2019)

@penelopejane - That's a GREAT idea!  nice and big and pour-able, too!


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## maxine289 (Apr 30, 2019)

DeeAnna said:


> No -- masterbatched NaOH won't evaporate; it will absorb water and you don't want that. Also exposure to air will reduce the purity of the NaOH because it reacts with carbon dioxide in the air.
> 
> In addition, you want to be safe and minimize the chance for spills or leaks. A screw-on lid is safest -- a snap on lid is not as good.
> 
> edit: Never fasten a lid on tight while the lye solution is still hot. You don't want pressure to build up in the container. Just put the lid or cap on the container but leave it loose until the solution cools. Then cap the container tightly.


If it absorbs water, I assume that changes the lye ratio thereby increasing the amount of water in the batch.  Other than that, are there any ill effects?  I've not noticed any.


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## atiz (Apr 30, 2019)

maxine289 said:


> If it absorbs water, I assume that changes the lye ratio thereby increasing the amount of water in the batch.  Other than that, are there any ill effects?  I've not noticed any.


It would increase the amount of water, also in the masterbatch --- so unless you measure every time how much the total water increased, you won't know exactly how much solution you need to have a given amount of lye. That seems a bit inconvenient when it comes to masterbatching. (It basically results in a variable % of masterbatch solution, a % you might not even know.) I wasn't even aware of the CO2 reaction but that just seems to make the situation worse; at the end of the day you'll have a considerably weaker mb than you think you have, which will result in some extra superfat in your soap.


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## DeeAnna (Apr 30, 2019)

maxine289 said:


> If it absorbs water, I assume that changes the lye ratio thereby increasing the amount of water in the batch.  Other than that, are there any ill effects?  I've not noticed any.



What I said already -- "...Also exposure to air will reduce the purity of the NaOH because it reacts with carbon dioxide in the air..." and "...you want to be safe and minimize the chance for spills or leaks..."


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## IdahoSoapMaker (Apr 30, 2019)

Cal43 said:


> ok here I go...
> 
> 50/50 measured  and mixed
> 
> ...


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## maxine289 (Apr 30, 2019)

DeeAnna said:


> What I said already -- "...Also exposure to air will reduce the purity of the NaOH because it reacts with carbon dioxide in the air..." and "...you want to be safe and minimize the chance for spills or leaks..."


I get the safety issue; I just didn't mention it. I wanted to understand the effect of a reduction in purity on the final soap.  Sometimes I make up my lye solution but then something happens and I have a delay of several days, or even weeks, before I actually use it. (It sits covered at the back of my counter out of the way).  I wondered what impact the reduction in purity might have on the finished soap.  I understand the possible increase in the superfat.


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## jcandleattic (Apr 30, 2019)

maxine289 said:


> I get the safety issue; I just didn't mention it. I wanted to understand the effect of a reduction in purity on the final soap.  Sometimes I make up my lye solution but then something happens and I have a delay of several days, or even weeks, before I actually use it. (It sits covered at the back of my counter out of the way).  I wondered what impact the reduction in purity might have on the finished soap.  I understand the possible increase in the superfat.


decrease in purity would also result in a very soft, unsaponified soap. Yes, increase the superfat, but also not completely saponify the oils in an effecient way.


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## DeeAnna (Apr 30, 2019)

_"...I wondered what impact the reduction in purity might have on the finished soap. I understand the possible increase in the superfat...."_

Increased superfat. 
Overly soft soap due to low NaOH and high water content.
Soap batter doesn't come to trace.
Possible emulsion failure and separation in the mold.


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## maxine289 (Apr 30, 2019)

Good to know.  Thanks, jcandleattic and DeeAnna.


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## Susie (Apr 30, 2019)

Don't fret about a minor delay in using it, but if you are going to wait a long time (several weeks to several months), make a SDSB Super Dry Storage Bucket.  Take a 5 gallon bucket and purchase a gamma lid.  Pour some of the old fashioned non scoopable cat litter (the clay kind) into the bottom.  Purchase the smallest Damp Rid that comes with the basket and container.  Put that in the center (follow directions on package).  Put bottles of NaOH, KOH, or masterbatched lye around the Damp Rid container.  Seal it up and resist the urge to re-open it until you really need it.  That's the only way I can keep my masterbatch from gaining weight.  This is not my invention, I learned it on this forum some time ago, and I would really love to thank whoever did figure it out.  I just can't remember who it was, but DeeAnna was in on the discussion somewhere, IIRC.


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## maxine289 (May 1, 2019)

Susie said:


> Don't fret about a minor delay in using it, but if you are going to wait a long time (several weeks to several months), make a SDSB Super Dry Storage Bucket.  Take a 5 gallon bucket and purchase a gamma lid.  Pour some of the old fashioned non scoopable cat litter (the clay kind) into the bottom.  Purchase the smallest Damp Rid that comes with the basket and container.  Put that in the center (follow directions on package).  Put bottles of NaOH, KOH, or masterbatched lye around the Damp Rid container.  Seal it up and resist the urge to re-open it until you really need it.  That's the only way I can keep my masterbatch from gaining weight.  This is not my invention, I learned it on this forum some time ago, and I would really love to thank whoever did figure it out.  I just can't remember who it was, but DeeAnna was in on the discussion somewhere, IIRC.


Thanks for the information.


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## DeeAnna (May 1, 2019)

The idea came from Boyago who doesn't post here anymore. I did a little video about how I made mine, but it was his suggestion that sparked my interest.


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## Susie (May 2, 2019)

DeeAnna said:


> The idea came from Boyago who doesn't post here anymore. I did a little video about how I made mine, but it was his suggestion that sparked my interest.



Thank you!  That one thing has kept me in soapmaking.  If I had not been able to control the moisture absorption, I would have quit out of sheer frustration of not being in control of my results.  And it is cheap!  $10 saved the day!


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## sudszensoaps (May 2, 2019)

Huh, this is an entirely new concept to me. I use room temperature process using the heat of the newly mixed lye added to solid oils, then mixing in liquid oils. It doesn't take long and works fine. Of course I don't make more than a 5 lb batch.


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## DeeAnna (May 2, 2019)

Room temp method is nice if it works, but it is best suited to recipes that don't have a high % of solid fats like palm, tallow, and lard that require a fair amount of heat energy to fully melt. Even if I use a hot lye solution with my high lard recipes, I'd still have to add additional heat to get the lard fully melted. So there's no great advantage to using the room temp method for the recipes I make. I didn't masterbatch lye solution for a long time, but now that I do, I really like it for the convenience and safety.


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## Susie (May 3, 2019)

Yep, me too.  The convenience is SUPER helpful now.  Takes next to no time to masterbatch lye, then the next time I make soap, it takes just a few minutes a batch.  But now I masterbatch everything.  Oils, additives, everything.  I even line my molds the night before and put the scent and colorants in the molds.  Saves a bunch of time the next day.


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## dotgiorgio (Aug 31, 2020)

I have a question about lye master batch.  I live in Phoenix and it gets very hot here.  My steps would be, make the master batch.  Let it cool down before putting a lid on it.  Storing it in my soap supply cabinet in the garage.  But I am wondering if that would be safe where the temp could get to 100 degrees or even a little more?  My garage is insulated but it still gets very hot in there.


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## Deborah Long (Aug 31, 2020)

I live in Phoenix, also, and I never store my masterbatched lye in the garage - way to hot!  Especially THIS summer where the temps were so far over 100!  Too much evaporation and heat.


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## SPowers (Aug 31, 2020)

I soap using a 2:1 water lye ratio.  This makes masterbatching super easy.  
If Masterbatching at 1:1  - if soap calc says you need 200 gr lye  & 400 gr water, then the m/b is 200 x 2 or 400 gr lye/water and the add'l water is 200.


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## TheGecko (Sep 1, 2020)

I started masterbatching because I got tired of being too tired to make soap.  

I masterbatch a total of 640 oz oils/butters split into four batches of 160 oz; this is because of the amount of hard oils I can melt on the stove in my pot. I could probably fit a single oil/butter in the pot, but in case of an emergency or shiney thing, it makes it easier to know exactly where I left off. Everything goes into a 5 gallon food safe bucket that was thoroughly cleaned and dried. Bucket sits next to my soap station (aka rolling kitchen island). Batter cools down to the consistency of a waffle batter, but is not hard.

While my oils are melting I start making my lye solution. Like with my oils/butter, I mix my lye/water in four batches, but mostly for safety as the solution is poured into a gallon jug when cool enough; with two batches per galllon jug. And I make it the same way I make it for a single batch...33% Lye Concentration and frozen distilled water. No muss, no fuss and best yet...no math.

When it comes time to make soap, I have a chart on my wall that has every mold listed and the total weight of oil/butter and lye solution need for each. I even have multiples of my cavity molds listed so I can use just one, or all of them. I grab my commercial paint stirrer and drill and give my oils/butter a good mix. I then take out my batter container, scoop out xx ladles of soap based on my chart (ladle holds about 4 oz)...weigh when I have reached the number...weigh, adjust, clean off the ladle and put the lid back on the bucket. Container goes into microwave...30 seconds per pound of oils. I then measure out my Lye Solution and it’s time to make soap. Since master batching, I’ve made more soap in the past month than I had in the past three. I’ve even come home from work and whipped up a couple of batches.

I’m getting another 5-gallon bucket to master batch the oils/butter for my Goat Milk Soap. I won’t be able to MB my lye solution since I use fresh Goat Milk, but I’m good with that. And come October with its cooler temperatures, I’ll start using a 35% Lye Concentration.


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## DeeAnna (Sep 1, 2020)

Masterbatched lye should be fine in a hot garage. The main downside from my point of view is if your MB lye straight from the garage is hotter than the temp at which you want to soap.

What's not a good idea is to store MB lye in a cold place. It needs to stay above 65F / 18C. If concentrated NaOH solution gets too cold, some of the NaOH will crystallize out, and that's a real mess to fix.


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