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iwannasoap

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If you are one of those who make beautiful, long lasting soaps, this is not for you.
I wrote this for people who might not realize the amount of water effects everything including the amount of oils and lye you use. If I have offended anybody I apologize and I readily admit that I have a lot to learn but I already know "Never to pour a whole bottle of salt in 30 oz of oil".

I am so glad your reading this! Weight and type of fats and the superfat are NOT the only factors that determine the NaOH weight.
" because it is what so many soapers don't realize which is also what stumped me because it is not taught - Especially from a bad program design of a soap calculator. (I know. I am a jobless programmer working in another field)

This is where a soap calculator fails! You cannot see it but I can show you and give you background info. Follow me here,

Get on your favorite soap calc. I used Wholesale supplies plus.

Your scenario is "You only want 50 oz of Castille soap to fill your mold"
CLick the radio button for NaOH of course
Type in 37.1 oz of oil (I know this will make 50.01 oz @ .135 SAP Olive, Calc uses .131 probably. Close enough)
Delete the "Water as % of Oils"
Click on the "Water : Lye Ratio" radio button
Type in "60:40"
5% SF and leave the rest blank no fragrance. (None of that matters anyways for this experiment)
Double click Olive oil and make it 100%
Make sure "Multiple tabs is selected"
Click calculate
Click "View or Print"
Leave the tab it brought and go back to the original tab
Leave everything the same but change the "Water : Lye Ratio" to 55:45
Click calculate
Click "View or Print"
Leave the tab it brought and go back to the original tab
Leave everything the same but change the "Water : Lye Ratio" to 50:50

Leave those tabs up for now so I can explain something. I will start from the simple to more of a soaping point of view.
First realize this - if you have a 16 oz cup and you wanted to fill it with 2 ingredients, whatever it may be, Ingredient 1 would be 8 oz and Ingredient 2 would be 8 oz. If you wanted to change those ingredients and still make 16 oz your next step would be Ingredient 1 changes to 7 oz and Ingredient 2 changes to 9 oz. to total 16. Next would be Ingredient 1 changes to 6 oz and Ingredient 2 changes to 10 oz for a total of 16 oz to fill the bottle.
This relationship between Ingredient 1 and 2 depend on each other. When ever one changes the other changes to be able to get the same total oz.

Now, lets make it a little more complicated. Lets put 3 ingredients in the bottle. Lets make 1 lye, 2 water, 3 oil.
Each one of those depend on each other but much more intricate since it involves 3 values.
This is actual numbers for this scenario to make 16 oz loaf
Watch closely
Water lye ratio 50:50
Olive oil: 358.62 gr (12.64 oz)
Water: 47.45 gr (1.67 oz)
Lye: 47.45 gr ( 1.67 oz.)
Please keep in mind, ounces are not as accurate as grams when adding this.
Results in 16 oz soap

If I increase my water 4.69 grams I will now have a total of 16.16 oz of soap. I don't want that. I want 16 oz because that will waste soap. Besides that, how will I screw on my bottle cap? So something else will have to decrease. The only thing I have left to decrease is the oil. And if I decrease the oil, I will HAVE to decrease the lye!

The new numbers will be
Oil: 354.94 g (12.52 oz)
Lye:46.96 g (1.66 oz)
Water: 51.65 g (1.82 oz)


Since I added more water, the oil in my recipe is now 354.94 gr (12.52 oz)
which is less then the first scenario to make the same 16 oz of soap.
This is also where the calc fails but going the opposite direction.

Go back to those tabs that you pulled up separately so I can demonstrate where a calc fails please. If you look closely you will see a couple of things wrong and I'll point that out. The end result though means that the real difference between the 50:50 ratio and the last one at 60:40 should actually be 9 more grams of lye (which is significant because ((49.037 - 46.65) * .135) but yet it does not show the oil increasing or decreasing. It only shows your total oz. going up. Remember, in this scenario you only want a certain amount to stay constant. No matter what that may be.

If you look through the tabs and add up all the weights (49.037 oz, 47.711 oz, 46.65 oz) You will see every thing, for some reason, stayed the same EXCEPT for your total amount. As you decreased (or increased) your water, your total weight ALSO went down. It went down to 46.65 oz and that is not what you wanted. You wanted 50oz.

The only way to fix that is to go back to the original tab and increase your oil amount to 39.54 (which is 2.44 oz greater then originally which takes more lye.)

So, you see, by adjusting the water your actually increasing or decreasing the amount of soap in the bar and possibly the loaf. Water does not turn into soap but it has everything to do with the amount of oil and lye that you use.



Some people might think that controlling the water you do not effect the oil amount and lye amount but if you were patient I hope I showed this not to be the case.


Hope this helps you. I really do. You will have more control and more soap in the same size bar.
 
Hi Iwannasoap, thanks for starting this thread. I'm sorry for being a little brash in my last reply to you, and I'm glad you pulled all the info you have shared throughout the forum in one spot.
 
I'm having a real hard time following this. My recipes have the same amount of oil every time, regardless of the amount I water I choose to use. The lye also stays the same, every single time.

Ditto.

Though the overall size of the batch of soap batter changes. This is logical since you are using more, or less, liquid.

I'm a bit lost too but what I THINK the OP is trying to say is that if you keep the overall batch size the same, but change the amount of water, that would mean to keep the same batch size your oil amount would have to change and thus your lye amount would change.

Probably doesn't matter if you don't mind what size the batch turns out to be
 
Ah, I see now.
I don't include my water when I talk about batch size, my 16 oz recipe is 16 oz of oils. This is the way to do it if you want consistent results. I know my 16 oz batch will always have the same amount of oils and lye, for that matter it always has the same amount of water too as I have a set ratio I use.

But, even if you change the water ratio, the lye amount won't change unless you also change the oil amount and I don't know why anyone would do that. A couple extra oz of water in a recipe isn't going to affect how your recipe fits in a mold unless you are using way too much water.
 
The reason I choose to take up more of my soap batter with water is so that I can easily achieve gel. I like the look, and I think it helps speed the beautiful crystalline structure of a well cured soap. That last bit I only learned about since I joined the forum. I'll have to read this again:
http://www.soapmakingforum.com/showthread.php?t=35831

When I first started soaping, a wee bit over two years now (hurray!) I was perplexed by all the different water amounts suggested by different soapers. Many of my questions brought me here. In one thread I found, a few soapers had been tracking soap weight during a year+ of cure time and charted the changes in graphs. I might not remember the results perfectly today, but I think by around 4-5 months 80% of the excess water had evaporated, while in a year's time, 90-95% of the excess water had evaporated. I *think* this process was a little slower for soaps with minimal water. I decided on a 35% lye concentration because there wasn't too much excess water, but I could gel my soaps easily.

At some point I calculated the shrinkage of my bars, so they could fit snuggly in some intricate handmade boxes at 4 months, and they still fit well, with just a tiny bit of space, after a year. I am too impatient to make fancy boxes now, but one way or another, I am happy with my soaps. I am pleased with their size, and the amount of actual soap in them :)
 
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I'm having a real hard time following this. My recipes have the same amount of oil every time, regardless of the amount I water I choose to use. The lye also stays the same, every single time.

Read the end then, but that is exactly the problem.
The desired amount you wanted is 50 oz.
Notice that when you add the Lye, water, and oil all together on a seperate calculator for each ratio that amount will get smaller and smaller. It will get down as low as 46.65 oz and that is not what you wanted. You wanted 50 oz.
The only way to solve that problem is to go back and raise your original oil amount to fill the same 50 oz space which proves that when your water increases or decreases your lye AND oil will change to make more soap and gel hotter. Please notice that when you change you oil amount your lye will go up also.
The program is supposed to loop the entire process over and over each time the print button is pressed, but it does not and many calculators do this.
It will probably do it going the reverse direction too so many soapers do not realize this and it will affect your soap.

The reason I choose to take up more of my soap batter with water is so that I can easily achieve gel. I like the look, and I think it helps speed the beautiful crystalline structure of a well cured soap. That last bit I only learned about since I joined the forum. I'll have to read this again:
http://www.soapmakingforum.com/showthread.php?t=35831

When I first started soaping, a wee bit over two years now (hurray!) I was perplexed by all the different water amounts suggested by different soapers. Many of my questions brought me here. In one thread I found, a few soapers had been tracking soap weight during a year+ of cure time and charted the changes in graphs. I might not remember the results perfectly today, but I think by around 4-5 months 80% of the excess water had evaporated, while in a year's time, 90-95% of the excess water had evaporated. I *think* this process was a little slower for soaps with minimal water. I decided on a 35% lye concentration because there wasn't too much excess water, but I could gel my soaps easily.

At some point I calculated the shrinkage of my bars, so they could fit snuggly in some intricate handmade boxes at 4 months, and they still fit well, with just a tiny bit of space, after a year. I am too impatient to make fancy boxes now, but one way or another, I am happy with my soaps. I am pleased with their size, and the amount of actual soap in them :)

For soaps with minimal water the process will be quicker but it can tread on a fine line of crumbly edges. To keep this from happening I use a 50 50 ratio of water and lye and then add about 15 more grams.

Ah, I see now.
I don't include my water when I talk about batch size, my 16 oz recipe is 16 oz of oils. This is the way to do it if you want consistent results. I know my 16 oz batch will always have the same amount of oils and lye, for that matter it always has the same amount of water too as I have a set ratio I use.

But, even if you change the water ratio, the lye amount won't change unless you also change the oil amount and I don't know why anyone would do that. A couple extra oz of water in a recipe isn't going to affect how your recipe fits in a mold unless you are using way too much water.

On a soap calculator it will not change. But your total amount will change to be able to use the same amount of lye. Add it up the next time with 3 different ratios. you will see total amount getting smaller or larger whatever you put in BUT it will not equal to the amount that you wanted.
Everything depends on everything to get the same amount in a loaf. As your water increases your oil and lye will have to decrease and visa versa. You just dont see it on a soap calc because they are not designed right. This is for people who want to get more soap out of the same size loaf. Water will not turn into soap. I do hope that you see it one day. Thank you

Exactly.
But in some cases, I have seen on here even, too much water is used and it causes problems with their soap. This is a way to realize that the more oil in a bar means more lye and it creates more soap to last longer then before!
Many people are under the impression that water has nothing to do with the calculation of lye and oil. I say it does becasue more water means less oil and less lye.

Hi Iwannasoap, thanks for starting this thread. I'm sorry for being a little brash in my last reply to you, and I'm glad you pulled all the info you have shared throughout the forum in one spot.

No problem, I enjoyed it. I needed to actually see for myself instead of seeing it on a spreadsheet.
 
The ratio of oil to lye does not change, and that's what I use a soap calculator for. Changing the water amount will change the initial weight and volume of the soap, but has no effect at all on oil to lye ratio UNLESS YOU CHANGE THE AMOUNT OF OIL when you change the amount of water.

The final dry volume of the soap will be determined by the oil weight, but more water will make the initial volume larger. The soap made with high water will shrink as the excess water evaporates, sometimes warping when it does, or getting ripples (especially HP, which is somewhat less uniform when done than CP).

I've made my molds to fit a particular amount of oil, with a bit of extra room in case I want to use extra water. I expect them to be less than completely full if I do a water discount -- I leave the oil weight the same (500 g for standard bars, 420 gr for the smaller bars my mother likes). HP soaps get a little extra water to start with, and usually a small amount after the cook to loosen them up, they mix and mold better that way.

I also like to keep things simple. The only time I pay any attention to the final weight of the batch is when I'm making tester bars for scents, and that's only to figure out how much to weigh out for each one. I don't sell soap, so the bar weight isn't an issue -- good thing as I have never manage to cut them very straight!
 
I think...maybe...that what you're saying is that you're constraining the batch size to 16 and allowing all the constituent amounts to change?

Whereas most of us constrain the oil weight and let everything else, change. Including the total batch weight.

In the case of most of us, with the oil weight stable (and the recipe the same), our lye weight will not change unless we change the super fat. Water, however, can go from a severe water discount all the way to full water.

In your case, with oil weights changing, the amount of lye is absolutely going to change. And with oil weights changing and lye weight changing, water weight is also going to change to make up the rest of the batch.

The consequences in both cases are normal and expected, and the most-of-us crew will produce a differing number of bars depending on our water weight. You'll produce the same, but the total composition will differ.

Neither is in error, it's merely a matter of perspective and what you constrain on your batches.
 
Basically, we each have our own preferred lye concentration. Iwannasoap likes 50%, I like 33-35%, you all might like something different. Iwannasoap has his own way of working out how to fit a batch in a mold, and doesn't like the idea of excess water.

The real difference I see is his soaps won't gel. A high water soaper might choose to prevent gel with the help of a freezer. I like gel, and force it when I have to.

I feel the need to end on a cheesy note: we are all in the same boat, it'll just take some of us a little longer to dry out our shoes

 
From what I can understand, the OP seems to be concerned about fitting a given volume of raw soap into a mold, and excited about the fact that if you use more water in your lye solution (40% solution vs, say 50% solution), you are going to have more total volume for a given mass of oil.

That's kind of a given, yes?

The ratio of lye used is determined by the mass of oil in the recipe, not by the amount of water used. If your intention is to have end up with a dry-mass soap that has a particular superfat %, the amount of water used is irrelevant to the amount of lye used - it's your choice, so long as you aren't going to overflow your mold.

(Of course, yes, if you choose to use a certain lye solution % in order to have a particular total volume in your mold, i.e. if you prioritize the water volume above all else, that will affect the maximum amount of oil and lye you can use to fit in your mold. You'll still end up with the same dry mass of soap after a long enough cure, but if your goal is to completely fill up your mold, well, there you go. However, that volume of water will NOT affect the ratio of lye to oil).

Soap calculators are NOT misleading. You do, however, need to know what you are doing and what is being calculated and what actually matters in the end.

ETA: If I was not clear enough above - if I use 1051.77g (37.1 oz) of OO and want a 5% SF soap, I will use 133.89 g (4.72 oz) of lye. Period. That does not change. The ratio of lye to OO is 0.127:1. Period. That does not change. I can make the soap with a 40% lye solution or a 26% lye solution or a 50% lye solution - my choice will affect how much water I use in my lye solution, but will not affect how much lye is needed. However, if my 40% and 50% solutions fit my mold (water + lye + soap), but I really want to use a 26% lye solution and it has so much water in it that it will not fit my wee mold, obviously I need to have less other stuff in there in so I don't overflow my mold. So my overall mass of oil needs to be smaller. So will, therefore, the amount of lye I use need to be smaller. However, if I still want to make a 5% SF soap, the ratio of lye to oil with steadfastly remain at 0.127:1.

By the same token, when I use 1051.77g of OO and 133.89 g of oil, the final cured mass of my soap will be identical after a long enough cure (time for evaporation), regardless of whether I used a ****-ton of water, or a 50% solution. I'll just get there faster with the latter.
 
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The ratio of oil to lye does not change, and that's what I use a soap calculator for. Changing the water amount will change the initial weight and volume of the soap, but has no effect at all on oil to lye ratio UNLESS YOU CHANGE THE AMOUNT OF OIL when you change the amount of water.

The final dry volume of the soap will be determined by the oil weight, but more water will make the initial volume larger. The soap made with high water will shrink as the excess water evaporates, sometimes warping when it does, or getting ripples (especially HP, which is somewhat less uniform when done than CP).

I've made my molds to fit a particular amount of oil, with a bit of extra room in case I want to use extra water. I expect them to be less than completely full if I do a water discount -- I leave the oil weight the same (500 g for standard bars, 420 gr for the smaller bars my mother likes). HP soaps get a little extra water to start with, and usually a small amount after the cook to loosen them up, they mix and mold better that way.

I also like to keep things simple. The only time I pay any attention to the final weight of the batch is when I'm making tester bars for scents, and that's only to figure out how much to weigh out for each one. I don't sell soap, so the bar weight isn't an issue -- good thing as I have never manage to cut them very straight!

If you want to keep your total weight the same, it will absolutely change unless you just want to change the consistency of your soap. In both adding water AND subtracting water, if the total weight remains the same, everything changes.
Try putting this on a spreadsheet sometime. You will see much quicker and faster what your actually doing.
I need to add one more thing. The composition of my soap will be the exact same if I add water or didn't add water because my lye and oils adjust to the water. However, it is other soaps that will not remain the same. That will be the difference and in addition, mine will remain the same weight whereas other soapers who do not realize this will lose a certain amount of soap. That would mean in a 50 oz loaf going from 50:50 extreme ratio to a 60:40, you will lose almost 5oz.

I think...maybe...that what you're saying is that you're constraining the batch size to 16 and allowing all the constituent amounts to change?

Whereas most of us constrain the oil weight and let everything else, change. Including the total batch weight.

In the case of most of us, with the oil weight stable (and the recipe the same), our lye weight will not change unless we change the super fat. Water, however, can go from a severe water discount all the way to full water.

In your case, with oil weights changing, the amount of lye is absolutely going to change. And with oil weights changing and lye weight changing, water weight is also going to change to make up the rest of the batch.

The consequences in both cases are normal and expected, and the most-of-us crew will produce a differing number of bars depending on our water weight. You'll produce the same, but the total composition will differ.

Neither is in error, it's merely a matter of perspective and what you constrain on your batches.

Thank you for that kind comment. I do have hidden goal though. While both are correct, it is for some (those who are defensive and their have been a few already) to realize that they can be a little more flexible and to know what is exactly really going on to know their recipes inside and out. It will help some. Others argue up and down that water has nothing to do with amount of lye and oil if total weight is to remain the same.
Knowing this also prevents a few problems that I have already seen on here from people asking help.
 
Soapee.com if you set it to ''adjust oil weights to include water in oils total'' it will only adjust based on the 38%water plus oil. In other words it doesn't really work properly unless you set your lye concentration superfat and all that BEFORE you add your oils to the list. So I believe this is where iwanttosoap is coming from. But there is a work around.
 
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"...While both are correct, it is for some (those who are defensive and their have been a few already) to realize that they can be a little more flexible and to know what is exactly really going on to know their recipes inside and out. It will help some. Others argue up and down that water has nothing to do with amount of lye and oil if total weight is to remain the same...."

I read that as an indirect jab at me, so I'll respond here with the same thing I said in the other thread where you made the same argument --

***

"...So, you see, by adjusting the water your actually increasing or decreasing the amount of soap in the bar and possibly the loaf. Water does not turn into soap but it has everything to do with the amount of oil and lye that you use...."

Um, thanks, but I went through all this some years ago and figured it out on my own. Perhaps others will benefit, however, so I'm glad you shared your point of view. That was a lot of work to write all that, and I appreciate the effort.

"...If I increase my water 4.69 grams I will now have a total of 16.16 oz of soap. I don't want that. I want 16 oz because that will waste soap...."

One point you're trying to make is that varying the amount of water in a recipe while holding the NaOH and fat constant will alter the total volume of the soap batter. Sure, no problem.

And you are also saying if you want to hold the volume of batter constant, but want to change the water content, then you have to alter the fat weight to maintain constant volume. I get that as well.

But here's the deal -- I honestly don't worry about small changes in batter volume that result from modest changes in the recipe. After making soap for awhile, I'm well aware that changing the water content or the kinds of fats or the superfat in my recipe will alter the total volume of the soap batter. But it's not going to change it enough to matter to me. Maybe to you, but not to me. I can't get enthused about agonizing over these details.

***

The calcs don't explain all the background that you want them to explain ... but they aren't "bad" [or deceiving] as you label them ... because it's not the mission of soap recipe calculators to educate. They are there to do a given set of mathematical calculations, plain and simple.

If you want to design your own calc that meets your own expectations and requirements, then by all means do it. I'm sure people will be interested to see what you can provide.
 
...
I need to add one more thing. The composition of my soap will be the exact same if I add water or didn't add water because my lye and oils adjust to the water. However, it is other soaps that will not remain the same. That will be the difference and in addition, mine will remain the same weight .../QUOTE]

The problem with that is that you're removing the very reason we choose different water concentrations in soap. They're not supposed to be the same.
The point is that they're different - different because we're making ghost swirls, different to encourage or discourage gelling, different because we want more or less working time. If the soap is exactly the same, there is no reason to change water concentration at all.
 
Others argue up and down that water has nothing to do with amount of lye and oil if total weight is to remain the same.
Knowing this also prevents a few problems that I have already seen on here from people asking help.

I haven't seen that from anybody with even minor experience--lye+oil will always be the same if the super fat is not changing. The amount of water won't influence the amount of lye one jot. (I'm including all associated lye-influencing materials in your "oil" amount, including citric acid, milk, and so on).

Changing the water does change the total recipe, of course, and it does alter the initial characteristics of the soap (long-term characteristics are, from what I've ever noted, essentially unaltered regardless of water amount).

It mostly makes a difference in initial trace speed and tendency to gel. As roundly noted, full water recipes gel pretty easily. Discounted water recipes don't, but can be forced using towels or CPOP or suppressed by putting them in the fridge or freezer.

The jab at DeeAnna wasn't a good idea; most of us learn (and have learned) a great deal from her and she most definitely isn't wrong here. The two of you aren't quite using the same vocabulary, but if you read over what I wrote, I said exactly the same thing DeeAnna did, just using different terminology and a different method of explaining it.

SoapCalc (and other calculators, including the one I whipped up for home use) aren't wrong. They're merely placing the emphasis, by default, on different constraints that you do.

That's hardly an issue, and like me, you wrote your own calculator that works better with your particular style. In fact, I may sit down and calculate and then program a batch constraint calculator. It's rare that I do so--a little overflow just goes into a guest soap mold--but it might be helpful.
 
When you've finished, could you publish the math? :mrgreen:

I've been mucking about with mine for a while (it's a pick-up and put down job, because I keep on adding ideas to what I want out of it ... and then wonder just how huge it's supposed to be :think: )

My current thought ... I've decided I need to account for the space that dividers take up in slab molds. And so I went "seriously?!" at myself, and put it back down again (for a while, until I just have to finish that one ... tiny ... modification).

That's hardly an issue, and like me, you wrote your own calculator that works better with your particular style. In fact, I may sit down and calculate and then program a batch constraint calculator. It's rare that I do so--a little overflow just goes into a guest soap mold--but it might be helpful.
 
When you've finished, could you publish the math? :mrgreen:

I've been mucking about with mine for a while (it's a pick-up and put down job, because I keep on adding ideas to what I want out of it ... and then wonder just how huge it's supposed to be :think: )

My current thought ... I've decided I need to account for the space that dividers take up in slab molds. And so I went "seriously?!" at myself, and put it back down again (for a while, until I just have to finish that one ... tiny ... modification).

Sure thing! I have to constrain something, and it's going to be a game of changing oil, lye, and water sizes until it approaches the proper weight.

I have a distinct feeling it's going to lead to a Newton-Raphson iteration to get the final answer.

Like you, this is totally on my "to do" list. Now let's not discuss how long that list really is...
 
Maybe it's the engineer in me -- I eventually get impatient with debating how many algebraic angels can dance on the head of a mathematical pin. Yes, I admit I've got my own personal soaping spreadsheet that goes far beyond Soapcalc and Soapee. But I also know real life soaping has a goodly dose of the empirical and the subjective and thus cannot be entirely defined by math. And that's okay too.

But if a person wants the challenge of nailing as much down mathematically as possible, then what about building in the calculations to account for the volume of those swoopy peaked tops ... and to account for the changes in cross sectional area for the inevitable times when one's mold isn't always perfectly level?

:mrgreen: Mmmm, but, hey, before I think of more things to add, I just glimpsed another fresh rabbit hole around here to jump into. Gotta find it fast before my dogs do, so bye till later! :mrgreen:
 
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