bar soap turn to liquid soap? possible?

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deafsoaper

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I came across an article talking about able to turn cured bar soap into liquid soap by grating the bar soap and add distilled water and simmer over a pot til melted together and leave it overnight and produced a thick cream but can add more water if it too thick and add some preservative because of the water... then put in a pump bottle and that it

is that true?
 
We've beaten this one to death multiple times. Despite all the claims of success you can find on the internet, it really doesn't seem to be possible. Here's one loooong thread where several of us tested several variations on this "make stable liquid soap from bar soap" theme -- Liquid soap with NaOH???

I know of only one valid method for making a stable liquid soap using NaOH for the alkali -- Roberto Akira's "Japux" process. He is a retired chemist who is really into the chemistry of soap making, and he developed the method because KOH is not legally sold to consumers in his home country of Brazil.

His method is not just a "grate bar soap and add water" process. It requires carefully chosen blends of fatty acids, strict control of the water content throughout the saponification and dilution process, and a precise method by which the soap is made. I have not tried making soap with the Japux method -- the process is complex enough that even I'm a little daunted. Roberto offers a paid course to train people to use his method -- he has a website where he offers the class.
 
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@deafsoaper It's not that hard to make real liquid soap. The key is to use potassium hydroxide (KOH) instead of sodium hydroxide (NaOH). You mix the soap batter to trace, and then either let it saponify on its own overnight (CP) or cook it (HP). Either way, you end up with what is called "soap paste" that is then diluted in water to make liquid soap.

Unlike bar soap, LS should have a very low scent and very low SF, or you will have separated oils floating on top of your LS. There are some great threads here that explain the process in detail. I hope you will give it a try!
 
@deafsoaper It's not that hard to make real liquid soap. The key is to use potassium hydroxide (KOH) instead of sodium hydroxide (NaOH). You mix the soap batter to trace, and then either let it saponify on its own overnight (CP) or cook it (HP). Either way, you end up with what is called "soap paste" that is then diluted in water to make liquid soap.

Unlike bar soap, LS should have a very low scent and very low SF, or you will have separated oils floating on top of your LS. There are some great threads here that explain the process in detail. I hope you will give it a try!
I want to do liquid soap eventually, it just on the back burner for now.

I just came across the article on net and remembered a couple people asking me about liquid soap and just thought it would be quick to use whatever old bar soaps and do the "grate and add water" method

so for the KOH... I can just replace the NaOH in my recipe with KOH 1:1 and let it saponify overnight and add water to desired consistency? that it?

I will check out other threads on liquid soap
 
so for the KOH... I can just replace the NaOH in my recipe with KOH 1:1 and let it saponify overnight and add water to desired consistency? that it?
Oops, I am sorry for any confusion; I was really comparing only the process of creating LS to the process of creating bar soap (i.e., combine lye solution + fats/oils and blend to trace). I didn't mean to infer that the ingredients or recipes are necessarily the same. But I can see how I might have created that misimpression, so I apologize and will try to clarify.

While there are similarities in the process, some oils behave very differently in LS than bar soap, so you will want to learn about that. More importantly, it takes a different amount weight of KOH compared to NaOH to saponify the same amounts of the same oils, so it is not a 1:1 swap. Fortunately, you can set the lye calculator to KOH and it will calculate the correct amount of KOH for you. :)
 
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You need the same number of molecules of KOH to make the same amount of soap as you do NaOH molecules.

But a given number of KOH molecules weighs more than the same number of NaOH molecules, so the weight of KOH will be quite different than the weight of NaOH.

It's vital to calculate every recipe with a soap recipe c@alculator to ensure you use the proper weight of KOH or NaOH, whichever one you need. A few times a year people swap NaOH for KOH or vice versa and they end up with an oily mess of soap or a hugely lye-heavy soap.
 
the overall opinion is that it's not possible, I tried it a few times, but now I won't do it again.

Haha... I'm laughing because this brings back a fond memory of when I first tried it! With all due respect to my knowledgeable, always helpful and esteemed, colleagues who would not steer you wrong, Just for fun, I'm here to write the dissenting opinion! it is easy to make and a kick to use, if you don't mind dipping into a bucket of mucus! 😂

Grate up a bar of Kirk's Original Coco Castile Natural Soap (or handmade coconut soap).
Dissolve 1 part soap in 8 parts water on the range top.
Store in a bucket with a lid until laundry day.
Use a cup of the stuff for a full load.
Add Calgon or 20 Mule Team Borax (water softener) and/or OxyClean to the water according to directions.
Wash as usual.
Add 1/4 cup white vinegar to the rinse cycle.
Rinse in cold water as many times as needed to get all the soap residue out. If your "whites" turn out dingy and stiff feeling you need to run it through the rinse cycle again.

That being said, I agree with @AliOop — you would be better off learning to make liquid laundry soap from scratch:

Zany’s 100% Coconut Oil Laundry LS
 
Haha... I'm laughing because this brings back a fond memory of when I first tried it! With all due respect to my knowledgeable, always helpful and esteemed, colleagues who would not steer you wrong, Just for fun, I'm here to write the dissenting opinion! it is easy to make and a kick to use, if you don't mind dipping into a bucket of mucus! 😂

Grate up a bar of Kirk's Original Coco Castile Natural Soap (or handmade coconut soap).
Dissolve 1 part soap in 8 parts water on the range top.
Store in a bucket with a lid until laundry day.
Use a cup of the stuff for a full load.
Add Calgon or 20 Mule Team Borax (water softener) and/or OxyClean to the water according to directions.
Wash as usual.
Add 1/4 cup white vinegar to the rinse cycle.
Rinse in cold water as many times as needed to get all the soap residue out. If your "whites" turn out dingy and stiff feeling you need to run it through the rinse cycle again.

That being said, I agree with @AliOop — you would be better off learning to make liquid laundry soap from scratch:

Zany’s 100% Coconut Oil Laundry LS

Okay I'm gonna give this a try! :D I can't help myself haha. Partly because I would really like it to work. I got a lot of soap scraps which I use as confetti in my new soaps, but it would be nice if I could do something else with it...
 
I got a lot of soap scraps which I use as confetti in my new soaps, but it would be nice if I could do something else with it...
That will work for hand soap! :thumbs:

BTW, If you have some 80 Proof vodka around, try 1 tablespoon per 16 oz diluted soap. Alcohol is known to melt soap and clarify LS along as you don't add too much.

HAVE FUN!
 
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That will work for hand soap! :thumbs:

BTW, If you have some 80 Proof vodka around, try 1 tablespoon per 16 oz diluted soap. Alcohol is known to melt soap and clarify LS along as you don't add too much.

HAVE FUN!

Don't know when I have time, I got some health issues, but this is number 1 on my soap list ;)

Haha... I'm laughing because this brings back a fond memory of when I first tried it! With all due respect to my knowledgeable, always helpful and esteemed, colleagues who would not steer you wrong, Just for fun, I'm here to write the dissenting opinion! it is easy to make and a kick to use, if you don't mind dipping into a bucket of mucus! 😂

Grate up a bar of Kirk's Original Coco Castile Natural Soap (or handmade coconut soap).
Dissolve 1 part soap in 8 parts water on the range top.
Store in a bucket with a lid until laundry day.
Use a cup of the stuff for a full load.
Add Calgon or 20 Mule Team Borax (water softener) and/or OxyClean to the water according to directions.
Wash as usual.
Add 1/4 cup white vinegar to the rinse cycle.
Rinse in cold water as many times as needed to get all the soap residue out. If your "whites" turn out dingy and stiff feeling you need to run it through the rinse cycle again.

That being said, I agree with @AliOop — you would be better off learning to make liquid laundry soap from scratch:

Zany’s 100% Coconut Oil Laundry LS
The 1 to 8 ratio of soap and water is in weight?
 
Yes. But here's another quick & easy way to use up scraps that you might like better...

I chop up about 200 grams of scraps into fairly equal size pieces. I put them in a 1-cup Pyrex. Hand sprinkle with a bit water and toss lightly to disperse the water. Nuke in the microwave on high for 1 minute. Let set for a minute or so.

While the soap is still a bit warm use gloved hands to knead the shreds well. Then roll into a ball or hand-shape into a circle or square. Once it cools it's ready to use. I put it in a soap dish at the sink for daily use.

Cheers!
 
Oh dear, now she's going to have to put a label on it that says it contains vodka! Maybe a hazard warning and a 'keep out of reach of children' warning. And make sure she is not selling to minors, to boot. LOL

☣️⚠️🍸
 
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