Soap Hardness

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Well-Known Member
Sep 12, 2007
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I know on the Calculator, it shows you the hardness of each oil you select or for the recipe you set. How does this affect the end result? In what way?

A soap recipe with 35 hardness is going to take longer to get hard than one set at 40? Does the 35 hard soap melt (from use) away faster than a 40 hard soap? If you let the 35 hard soap dry longer than the 40 hard soap, does it change how quickly it will melt away? Does a 35 hard soap get more squishy when wet than a 40 hard soap?

Getting it? Do I make any sense?
The hardness number does not refer to the length of time the bar will take to get hard or cure. But the overall hardness of the bar based on the oils and butters used. This number can sometimes be deceiving. For instance, a castile soap will, based on the hardness number, appear to be a softer soap, but if given a long enough cure, a castile soap is very hard. So yes, the cure time will also dictate how hard or soft your bar is. But, a bar with a higher percentage of softer oils, will for the most part never get as hard as a bar with a higher percentage of hard oils (like coconut, palm, pko. lard, babassu). Also, the softer the bar, the faster it will be used up. So this is the challenge a soaper faces, to make a bar that is hard enough to last, with great lather and lots of conditioning properties. I keep my soap recipes usually with a split of 50/50 or 60/40 (hard oils to soft oils).
For one recipe I set, I use:
Olive Oil 47%
Coconut Oil 29%
Palm Oil 19%
Sweet Almond Oil 5%

How do I find out the soft to hard oils? What is my percentage of soft to hard oils.