Struggling with the math involved in soap making

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Bee__rose

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I am not going to lie, math is not really my thing and its causing a lot of frustration with this soap making process.

I bought this soap making book, but all the recipes are for 2 bars of soap (using only 14oz of soap base for example). For the most part I'll be making soap in my 2lb mold. How do I calculate the difference? Or what is the easiest method. Feel dumb even asking the questions, which is why I'm so hesitant to even try CP soap. Cant group the percentage ratios.

Any suggestions are appreciated.
 
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Hi Bee_rose, here is also a forum sticky for how to calculate your batch size to fit your mold. https://www.soapmakingforum.com/threads/how-to-figure-how-much-oil-for-mold.2909/
CP soap making is so much fun, but can be a bit overwhelming at first. Ask any questions you have, and there are a lot of experienced people to help out. It is important to learn to use a lye calculator. I use soapcalc because that's what I started with, but a lot of people use soapee as well.
 
Hi Bee_rose,

There are 16 ounces in a pound, and the recipes in your soap making book use 14 ounces.

I know it's very rough, but doubling the recipes would give you twice as much soap and you know for sure it will fit in your mold, then you can adjust your multiplier up from there. Your multiplier is 2 in this example, and you use this to multiply each ingredient to get the amount you want.

The only ingredients you ALWAYS check with a calculator (like soapcalc or soapee) is the water and the NaOH - always check the NaOH amount.
The water is easiest to understand if it's the lye concentration is in the range of 30% to 33% for at least the first few batches (reducing the variables between different recipes helps understand the qualities that the oils and butters bring to your soap - the water amount can make a large difference to how your soap reacts during saponification and the cure).

*Edited to add the words "lye concentration" for clarity
 
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Is it ok to reply to this post now? This just caught my interest.
"the water amount can make a large difference to how your soap reacts during saponification and the cure"
Would love to know what the differences are apart from the cure time SaltedFig please. I usually use 35% water, what advantages is there for using lower?
 
Is it ok to reply to this post now? This just caught my interest.
"the water amount can make a large difference to how your soap reacts during saponification and the cure"
Would love to know what the differences are apart from the cure time SaltedFig please. I usually use 35% water, what advantages is there for using lower?

You may want to start your own thread with your question. This is the MP forum
 
...I usually use 35% water, what advantages is there for using lower?

Please take care -- I believe SaltedFig is talking about 30% to 33% lye concentration although I'm not entirely sure about that. I believe you are talking about 35% water as % of oils. These are different ways to calculate the amount of water for a recipe, and one isn't the same as the other. See: https://classicbells.com/soap/waterInSoap.html And you both are talking about soap made with lye, not about melt and pour soap.

It's not good form to divert the discussion away from the OP's topic. It would be best to start your own thread in the Beginners Forum to get your questions answered about water content in soap recipes.
 
... I believe SaltedFig is talking about 30% to 33% lye concentration ...

Thank you for highlighting that DeeAnna, reading back I had not written the sentence with clarity. Yes, I mean lye concentration. I will edit the original post to make that clear.

And you both are talking about soap made with lye, not about melt and pour soap.

The OP, Bee_rose, also mention wanting to try CP, so I gave both the information for easily working out the amount to multiply by to fit their mold, and a pointer in case the recipe book also contained the CP recipes they were looking to try.

Would love to know what the differences are apart from the cure time SaltedFig please

I see that DeeAnna has given you a link to her webpage in reply. I do hope you create a new topic if you still have some questions (it's a big topic!), but essentially this water range is "sweet spot" for water content and a good range to begin CP soaping from :)
 
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So if you are making MP soap in a 2-pound mold you want 2 pounds of MP soap. Unless you add lots of additives, which is not recommended, then it should all fit into the 2-pound mold. But if you just double the recipes for MP that you found, it will fit into your 2-pound mold with a bit of room to spare. I'd start there with the first soap.

When you have done one soap that way, see if the bars came out the size you want. If not, then try and figure out how much more you need to fill the mold. Come back and let us know and we can help you figure out a calculation or multiplier to get what you want.
 

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