Lye calculation help needed.

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Hmmm.. That's strange.. So these are both using the same oils? Just the water and lye is different?

The professionals aren't getting a full enough picture to be able to help you I think....
 
exact same recipe. The top one has its water and lye calculated by soapcalc and the second was my made up amounts.
 
I don't know about that. I made the recipe 4 times that day with 3 being my calculations and 1 being the soapcalc calculations.

I haven't messed up a batch for years and years and then after everybody told me it would be alright I tried the lye calcs on page one and what do ya know, it is sold lye heave dud batch.

The mixture is:
30% olive oil pomace
26% coconut oil
44% veg shortening
 
I don't know about that. I made the recipe 4 times that day with 3 being my calculations and 1 being the soapcalc calculations.

I haven't messed up a batch for years and years and then after everybody told me it would be alright I tried the lye calcs on page one and what do ya know, it is sold lye heave dud batch.

The mixture is:
30% olive oil pomace
26% coconut oil
44% veg shortening

Okay but what are the exact measurements? Grams and all of both recipes. How many grams of each oil for both recipes? How much water for both? How much lye for both? What are you using to measure? We need more information because something is definitely not correct.
 
I weigh it all out on scales

1200g coconut oil
1410g olive oil
2025g vegetable shortening
total= 4635

Water 940g
Lye 384g
40% lye 60% water which means that of the 940g of water, 40% of that is lye. A 40% lye solution.

lye calc
660g lye
1225g water

Which I plugged in as 35% lye concentration
 
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I weigh it all out on scales

1200g coconut oil
1410g olive oil
2025g vegetable shortening
total= 4635

Water 940g
Lye 384g
40% lye 60% water which means that of the 940g of water, 40% of that is lye. A 40% lye solution.

lye calc
660g lye
990g water

Which is 66% lye
34% water

Id like to know how you are calculating this.. what method is being used because it’s wrong.

To calculate the percentage:

1.Add the two parts to create the whole number, so 660g lye + 990g water = 1,650g together

2.To find what percentage the lye is of that number, you’re going to divide 660g of lye by the whole number, 1,650g; So 660 divided by 1,650 will equal 0.4.

3.To convert this decimal all you have to do is multiply it by 100, so 0.4 x 100 = 40.

4.All that is left is to add the percentage sign, so 40%.

What this shows is that 660g of lye, and 990g of water = 40% lye concentration.

I weigh it all out on scales

1200g coconut oil
1410g olive oil
2025g vegetable shortening
total= 4635

Water 940g
Lye 384g
40% lye 60% water which means that of the 940g of water, 40% of that is lye. A 40% lye solution.

lye calc
660g lye
1225g water

Which I plugged in as 35% lye concentration
That’s not how percentages work.
 
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You caught that before my edit. I added 1225g of water. I was looking at my earlier notes and not my lab book.

My lab book had ticks at all the measurements so that I preformed the experiment perfectly.

I looked at at that one and thought no way.

I do my calculations as 660/990*100 which equals 66.6.

So 384/940*100 = 40

I was say no no no for ages about this and knew it would fail, so I came here to ask and they told me to go for it, so I did and it failed. This has been so annoying. This whole thing has been a nightmare.

Even if I did make a mistake and put 990g of water instead of 1225, the soap should still have been at least usable.
 
You caught that before my edit. I added 1225g of water. I was looking at my earlier notes and not my lab book.

My lab book had ticks at all the measurements so that I preformed the experiment perfectly.

I looked at at that one and thought no way.

I do my calculations as 660/990*100 which equals 66.6.

So 384/940*100 = 40

I was say no no no for ages about this and knew it would fail, so I came here to ask and they told me to go for it, so I did and it failed.
That’s where you’re going wrong. You do not divide by part of the number. You need to add the two parts to get the WHOLE number. It’s not 384/940*100=40 it’s 384/1,324*100=29

You need to add the two together or else you’re calculating 940 as the whole number, which isn’t in this case.
 
But even if I plug 29% into lye calc, it still gives me 660g of lye but with a large amount of water.

If I put a large amount of water with it will it dilute the lye down enough to not ruin my soap?
 
But even if I plug 29% into lye calc, it still gives me 660g of lye but with a large amount of water.

If I put a large amount of water with it will it dilute the lye down enough to not ruin my soap?
How did you come up with the amount of water and lye to use in the first place? For the size of your batch, the numbers the calculator is giving you is correct, what you don’t understand is that your batch size matters. 660g lye and 990g of water is 40% lye concentration, but 172g of lye and 258g of water is also a 40% lye concentration. What happened is you calculated this recipe wrong in the beginning and the calculator is telling you that you aren’t using enough of the lye solution for the amount of oils you’re using.
 
But even if I plug 29% into lye calc, it still gives me 660g of lye but with a large amount of water.

If I put a large amount of water with it will it dilute the lye down enough to not ruin my soap?
Not sure what you mean about large amount of water.... The calcs are made to give you the appropriate amount of water that should be used with whatever lye amount it comes to, when you choose the concentration.

You didn't mention superfat or I missed it so I used 8%. I also wasn't sure what your shortening consists of but as example I tried two different lye concentrations. It will matter because different fats will need different lye amounts to saponify. With the same concentration, you'll get different lye amounts n water amounts.

It's an ok recipe.. Just low on longevity for me. And for 30% olive oil I'd cure it a bit more than 6wks.
 

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It gave me this, which is about what I used. Which puts me back at square one, because it makes the soap lye heavy.

Capture.PNG
 
It gave me this which is about what I used. Which puts me back at square one, because it makes the soap lye heavy.

View attachment 41690
No matter what, 4635g of the oils you’re using is going to need 660g of lye to sopanify. The only thing you’re changing with the percentages is the water. It won’t be lye heavy. No matter if it’s 33% concentration, 40%, or even 20%.. it’s still going to have 660g of lye because that’s how much lye consumes 4635g of the oils you’re using.
 
Why is it so hard and crumbly after only 24 hours in the mold?

Does normal soap get cracks in it?

I have a batch on now. I am going to put exactly that lye calculation into it and demold after 12 hours. If this one fails I am going to incorporate more soft oils.

It is all in the name of formulating a bigger batch.
 
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You show you are using Crisco with Palm in your recipe. Are you actually using Crisco? Or another vegetable shortening? That too may be part of your problem. You should be able to use a 33% lye concentration with your recipe if it's factual without a problem.
 
You show you are using Crisco with Palm in your recipe. Are you actually using Crisco? Or another vegetable shortening? That too may be part of your problem. You should be able to use a 33% lye concentration with your recipe if it's factual without a problem.

Crisco is not the veg shortening, it's copha which is CO, so that makes the recipe 70% CO and 30% OO. I mentioned this some posts back.
 
Crisco is not the veg shortening, it's copha which is CO, so that makes the recipe 70% CO and 30% OO. I mentioned this some posts back.
That's what I thought. Couldn't find the post but it niggled in the back of my mind.

Thank you!!! That's the OP's problem then. Using the wrong item in the calculations. But apparently he's not listening to the advice given and still using wrong calculations. It takes more lye to saponify CO than Crisco w/palm.
 
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I missed that about the shortening. Sheesh.....

The crumbly is cutting too late in that case maybe.. High coconut oil soaps take less time to harden up. It also means 8% superfat isn't enough. @Auxotroph have you actually told us what the ingredients of your shortening are, and at what percentages? As I said earlier different fats require different lye amounts, regardless of concentration. Take a pic of the ingredients list or something..
 
1200g coconut oil
1410g olive oil
2025g vegetable shortening
total= 4635
Crisco is not the veg shortening, it's copha which is CO, so that makes the recipe 70% CO and 30% OO.
So based on this information, try plugging it in to the soap calc like this:
CO 1200g + 1418g = 2618g (this is the original 25% CO + 70% CO in the shortening)
OO 1410g + 607g = 2017g (this is original 30% OO + 30% OO in the shortening)
I plugged into the soap calc with 40% lye solution and 20% Superfat (which I think is too high, this soap is only 50-ish% CO, in my shoes I would do 12-15% SF and give it a good long cure).
upload_2019-9-26_9-29-48.png


You can see even with 20% superfat, the lye is still quite more than you are using. Your soap has a very high superfat - in order to get the lye number from the recipe in post #46 I had to plug in a 49% superfat.

upload_2019-9-26_9-33-40.png


That means half of your oils are not being made into soap. This is not good soap.

To summarize what has been said previously:
Every oil has an SAP value - this how many milligrams of sodium/potassium hydroxide are needed to completely saponify 1g of oil. This number varies for each oil. It will even vary slightly from calculator to calculator as the number is typically given in a range, so some calcs will be set differently on that range. All the calcs will still give you accurate calculations as these variances are typically in thousandths of a gram (.00xg).

Lye is calculated by the oil used. (amount of oil x SAP value = amount of lye)

Superfat/lye discount: two terms used interchangeably that result in a percentage of oils left unsaponified. Typically in a soap calc it is called superfat, but the calculations will reduce the amount of lye used to whatever percentage you specify.

Lye concentration: The calculated lye amount + liquid. You can change the concentration in the range of 25% (more water) to 50% (less water), but this will not change the amount of lye used.

Simply put: I think you need to spend some time studying how soap is made.
 
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