Lye Calculator

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Abrachibi

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I know soap can be made without lye calculator. I do that myself. disolve my caustic soda in water of any amount then look for the spicific gravity of lye then measure my oils and lye at the ratio of 2:1. But someone told me he uses 4kilograms of caustic soda, dissolve in 4 litters of water and combine the lye solution with 4 liters of oil without cheking the specific gravity of the lye water. I do'nt know the outcome of such a soap. Does anyone has another method of soaping without using lye calculator.
 
Is there a reason why you want to use this kind of method? Is your alkali not very pure? Or are you using a random mixture of fat? Or are you using wood-ash lye? Or are you using a boiled method of making soap?

I agree with the others -- if you have reasonably pure alkali and know the specific types of fats going into the soap, why not use a recipe calculator? You can do the math by hand or use an online calculator as is best for your situation. There's no reason not to.

edit: The approximations you and the other man are using are not really wise for making soap with a hot process or cold process method. If using a boiled method, an approximation will work okay because the boiled method allows you to correct for excess lye or excess fat at the end of the boiling process.

"...disolve my caustic soda in water of any amount then look for the spicific gravity of lye then measure my oils and lye at the ratio of 2:1. But someone told me he uses 4 kilograms of caustic soda, dissolve in 4 litters of water ..."

If the other person is using alkali of a known purity and always dissolving 4 kg of the alkali in 4 L of water, that gives a fixed alkali concentration. How is that materially different than your method in which you use a hydrometer to check the concentration?
 
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Okay, thank you all. You might just find yourself in asituation where you have no access to calculator that means you will never soap. A serious delima

Is there a reason why you want to use this kind of method? Is your alkali not very pure? Or are you using a random mixture of fat? Or are you using wood-ash lye? Or are you using a boiled method of making soap?

I agree with the others -- if you have reasonably pure alkali and know the specific types of fats going into the soap, why not use a recipe calculator? You can do the math by hand or use an online calculator as is best for your situation. There's no reason not to.

edit: The approximations you and the other man are using are not really wise for making soap with a hot process or cold process method. If using a boiled method, an approximation will work okay because the boiled method allows you to correct for excess lye or excess fat at the end of the boiling process.

"...disolve my caustic soda in water of any amount then look for the spicific gravity of lye then measure my oils and lye at the ratio of 2:1. But someone told me he uses 4 kilograms of caustic soda, dissolve in 4 litters of water ..."

If the other person is using alkali of a known purity and always dissolving 4 kg of the alkali in 4 L of water, that gives a fixed alkali concentration. How is that materially different than your method in which you use a hydrometer to check the concentration?
4 kg of caustic soda in 4 litters of water doesn't gives you a specific gravity of 1275. you must find your specific gravity and have it at 1250 or 1275. You can't just assume fixed alkali concentration of 4kg caustic and 4liters of water to have your standard S.G of 1250 or 1275. When I get my S.G I use my oils and lye at ratio of 2:1 and have a perfect soap that takes 4 weeks to get hard.
 
Actually a solution made with 4 kg of commercial NaOH in 4 L (4 kg) water will have a specific gravity of 1.54. You do not have to measure specific gravity to make a consistent lye solution if you are using commercial NaOH of known purity. You can use specific gravity OR you can use a decent scale. Either way, you can get an accurate, repeatable result.

Even if you do choose to measure specific gravity as a check on the concentration, it does not have to be in the 1.250-1.275 range for making soap. I use NaOH solutions with specific gravities ranging from 1.28 to 1.54 and get good results from them all.

It is your choice to use lye solution in the 1.25 to 1.28 range, because you have learned this method makes good soap for you. I can see why you have no reason to change, and that is fine, but you may want to broaden your understanding of soap making.

Just because your method works for you, doesn't mean other people are wrong if they use another method. Your method is valid. And so is his. And so is mine.

Study the chemistry and math of saponification in more depth and learn other ways of thinking about how to make soap. You might still prefer your method, and again that is fine, but with more knowledge, you will understand your way is not the only way.

Okay, thank you all. You might just find yourself in asituation where you have no access to calculator that means you will never soap. A serious delima

As long as I have paper and pencil, I can calculate a soap recipe. Online soap recipe calculators have only been around for 20 years or so, but soap makers did just fine before that time without the internet, hand held calculators, or hydrometers.

Your assumption that I can't make soap without a calculator is no more valid than if I would assume you can't make soap if your hydrometer breaks. If you understand the chemistry and math of saponification, you have the tools that will let you use other alternatives if you can't use your usual method.
 
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Okay, thank you all. You might just find yourself in asituation where you have no access to calculator that means you will never soap. A serious delima
Not all lye calculators are internet dependent. I have a stand alone one on my computer, and used to have one on my phone, neither of which require(d) internet access.

Okay if I am faced with no electricity I might be up a creek for a little bit, but as common as the written word is, there are also several printed books with instructions on how to calculate lye for making soap and some of us have those as well or can dig one up if need be. Or maybe we already have a tried and true recipe that we can fall back on and not have to worry about making new calculations.
 
Not all lye calculators are internet dependent. I have a stand alone one on my computer, and used to have one on my phone, neither of which require(d) internet access.

Okay if I am faced with no electricity I might be up a creek for a little bit, but as common as the written word is, there are also several printed books with instructions on how to calculate lye for making soap and some of us have those as well or can dig one up if need be. Or maybe we already have a tried and true recipe that we can fall back on and not have to worry about making new calculations.
Earlene, just print off a table of NaOH sap values for the fats you use (and keep it in a safe place until the power goes out), borrow a triple beam balance (unless you already have one), fire up the camp stove or grill to melt your hard fats, and you'll be good to go. :)
 
Actually a solution made with 4 kg of commercial NaOH in 4 L (4 kg) water will have a specific gravity of 1.54. You do not have to measure specific gravity to make a consistent lye solution if you are using commercial NaOH of known purity. You can use specific gravity OR you can use a decent scale. Either way, you can get an accurate, repeatable result.

Even if you do choose to measure specific gravity as a check on the concentration, it does not have to be in the 1.250-1.275 range for making soap. I use NaOH solutions with specific gravities ranging from 1.28 to 1.54 and get good results from them all.

It is your choice to use lye solution in the 1.25 to 1.28 range, because you have learned this method makes good soap for you. I can see why you have no reason to change, and that is fine, but you may want to broaden your understanding of soap making.

Just because your method works for you, doesn't mean other people are wrong if they use another method. Your method is valid. And so is his. And so is mine.

Study the chemistry and math of saponification in more depth and learn other ways of thinking about how to make soap. You might still prefer your method, and again that is fine, but with more knowledge, you will understand your way is not the only way.



As long as I have paper and pencil, I can calculate a soap recipe. Online soap recipe calculators have only been around for 20 years or so, but soap makers did just fine before that time without the internet, hand held calculators, or hydrometers.

Your assumption that I can't make soap without a calculator is no more valid than if I would assume you can't make soap if your hydrometer breaks. If you understand the chemistry and math of saponification, you have the tools that will let you use other alternatives if you can't use your usual method.
DeeAnna - Thank you so much for sharing your knowledge. Your answers contain the type of information I would like to learn and know about making soap. There are so many books, blogs, groups, opinions, etc, that I have no idea how to get started with learning the science. How would you suggest I start on the journey of learning the science behind the soap? Would you please suggest books and/or classes? I have started with your "SoapyStuff" page for now. FYI - I understand all the terms in your replies except "boiled method of making soap", which I will research. Also, I have made cold process, hot process and liquid soap. Many kind thanks in advance.
 
@KimW -- Sorry for not replying sooner. I just read your post today.

The boiled method was the method used by all soap makers, large and small, to make soap in the past. It is still used today by medium to larger soap makers.

As far as I can tell, the "boiled" method of making soap is seldom used by the small-scale soap makers I've encountered in person or online. I think some small-scale soapers try a batch or two as a curiosity or perhaps to pass a Guild exam, but that's about it.

It's a time consuming method that works best when there's a large kettle of fat to be turned into soap. That's why the frontier soap kettles were huge cauldrons -- if you're going to spend a day or two making soap, you need to make a big batch to make the effort worth the time and trouble.

People have long known how to make soap using the cold process and hot process methods as well as the boiled method, but the boiled method was long preferred when fats and lye varied a lot in purity and the purity could not be easily measured. Many small scale soap makers today have the luxury of using fats that have a consistent quality and alkalis with a consistent purity.

Boiled soap is usually finished so it is "tongue neutral" (meaning no excess lye and no excess fat) or "sharp to the tongue" (meaning slightly to moderately lye heavy). The soap tends to keep longer due to zero superfat -- that will be especially true if less-than-fresh fats are used to make the soap.

I've rambled on long enough! I have an article and a couple of videos on "salting out" soap scraps, which basically teaches a person some of the basics of the boiled method. Here's a link -- Soapy Stuff: Salting-out soap
 
@KimW -- Sorry for not replying sooner. I just read your post today.

The boiled method was the method used by all soap makers, large and small, to make soap in the past. It is still used today by medium to larger soap makers.

As far as I can tell, the "boiled" method of making soap is seldom used by the small-scale soap makers I've encountered in person or online. I think some small-scale soapers try a batch or two as a curiosity or perhaps to pass a Guild exam, but that's about it.

It's a time consuming method that works best when there's a large kettle of fat to be turned into soap. That's why the frontier soap kettles were huge cauldrons -- if you're going to spend a day or two making soap, you need to make a big batch to make the effort worth the time and trouble.

People have long known how to make soap using the cold process and hot process methods as well as the boiled method, but the boiled method was long preferred when fats and lye varied a lot in purity and the purity could not be easily measured. Many small scale soap makers today have the luxury of using fats that have a consistent quality and alkalis with a consistent purity.

Boiled soap is usually finished so it is "tongue neutral" (meaning no excess lye and no excess fat) or "sharp to the tongue" (meaning slightly to moderately lye heavy). The soap tends to keep longer due to zero superfat -- that will be especially true if less-than-fresh fats are used to make the soap.

I've rambled on long enough! I have an article and a couple of videos on "salting out" soap scraps, which basically teaches a person some of the basics of the boiled method. Here's a link -- Soapy Stuff: Salting-out soap
Thank you so much!
 
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