Weekend Math

Did you know that soap making is chemistry? And did you further know that chemistry requires math? Yes, folks. I have to do math on weekends. I have a full time job so soap making usually only takes place on weekends, and let me tell you; it requires a lot of math!

Take this weekend, for example. I really wanted to make more soap than I usually do because of upcoming holiday shows and festivals. So I made 15 pounds. And I wanted to make 10 pounds of one soap and 5 pounds of another. And there are 3 different molds. 

In order to figure out the total weight of the ingredients needed, I had to measure the inside height, depth and width of each mold and blah blah blah times 40%.


But that’s not all. Each of these soaps is made up of seven different oils and butters. So I needed to add those together (God bless soap calculators!!!!!) in the right proportions in order to be sure to have the right amount. AND then I needed to determine how much lye water to add to the concoction in order to make my best soap. 

Have I said God bless soap calculators?

Once I determined the correct amounts of each element, I had to measure it. With a very precise scale. Tip a little too much of any oil into the mixture with other oils and your recipe will not necessarily turn out the way you envisioned. I say this with the voice of experience.

Now comes the fun part! You know how when you measure something and you’re so sure you’ve got it right but you continue to second guess yourself? No? Well, I do. So the entire time I was stirring and pouring my first 10 pound batch I was having “should I” “could I” kinds of thoughts, along with “did I” and “what if I didn’t” kinds of thoughts. I do a lot of mental hand-wringing when it comes to things like this. If I bought a car…no buyers remorse. A house…again, nothing. But making a 10 pound batch of soap? All. The. Time.

That was yesterday. Today, I cut my 10 pounds and weighed each bar as I cut. Yes, I’m required to put the total weight on soap that I sell, so I weigh each as it’s cut and weigh it again after about 4 weeks and then at about 6 weeks to be sure that the moisture has all evaporated and the bar is hard and won’t lose more weight.

But I digress. Today I cut my 10 pounds and it’s gorgeous. No color. No fragrance. Smells a little like shea butter, and if I’m honest, I don’t really like that smell much, but it makes an absolutely fabulous bar of soap. 

I’ll wait a day or two and then bevel the edges. I love to have beveled edges on soap because if I don’t, I don’t really like the feel of the brand new soap on my skin because the edges are too hard and it kind of hurts. I love a little softer feel so I have to imagine that others do as well. 

Six weeks from now, this will be a beautiful hard soap that others will love because it’ll look nice, feel great on their skin and do a great job getting them clean. But for now, I’ll just bask in the success of another Saturday well spent.

Despite the math.

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