Specific gravity and curing
- Thread starter Michaelsy
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Specific gravity (sp gr) is just one way to measure the concentration of a caustic soda solution. An caustic soda solution with this specific gravity has an NaOH concentration of about 24.5% by weight.
The strength of the solution affects how you MAKE the soap, but it has little effect on what happens after saponification is finished. All soap should be cured for the best performance -- most abundant lather, longest life, and the most gentleness to the skin.
A caustic soda solution of 24.5% would be on the low side for many soap makers here. In other words this lye solution contains more water than most people would prefer to use. Many people in this group use caustic soda solutions from 28% concentration (1.31 sp gr) to 40% (1.44 sp gr).
A specific gravity of 1.275 is not "the standard" for making soap. Making a caustic soda solution to this specific gravity may work best for the type of caustic soda you have and the way you make soap. But it is not the only way the strength of a caustic soda solution can be measured, nor is that the only concentration that can be used for soap making.
Here is a recent discussion that might be helpful to you -- Lye Calculator
The strength of the solution affects how you MAKE the soap, but it has little effect on what happens after saponification is finished. All soap should be cured for the best performance -- most abundant lather, longest life, and the most gentleness to the skin.
A caustic soda solution of 24.5% would be on the low side for many soap makers here. In other words this lye solution contains more water than most people would prefer to use. Many people in this group use caustic soda solutions from 28% concentration (1.31 sp gr) to 40% (1.44 sp gr).
A specific gravity of 1.275 is not "the standard" for making soap. Making a caustic soda solution to this specific gravity may work best for the type of caustic soda you have and the way you make soap. But it is not the only way the strength of a caustic soda solution can be measured, nor is that the only concentration that can be used for soap making.
Here is a recent discussion that might be helpful to you -- Lye Calculator
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