Skip to main content

3 - Using caustic soda: the online calculators

0 - Why and how to make your own soap?
1 - How: the saponification process
2 - Using caustic soda: safety precautions
3 - Using caustic soda: the online calculators

The process of saponification requires a precise quantity of lye; this quantity varies depending on the oil(s) you use. So always use a lye calculator, even if you reuse a recipe seen on the internet (check twice!). 

The Sage

I mostly use The Sage calculator


Using caustic soda: the online calculators
  •  Make sure to choose the right weight measurement.
  •   Sodium hydroxide (already checked) is the lye we use for solid soap. Potassium hydroxide is used for liquid soap.
  • If you're using lye flakes/beads, just fill in the oil information. In some countries, at least in France, you can buy water and lye already mixed, that's what "liquid lye solution" is for. The concentration that you have to write in the box must be around 30%. 
 ***
Using caustic soda: the online calculators
  • Enter the amount for each oil you want to use and then click on "Calculate lye" 
  *** 
Using caustic soda: the online calculators
  • The next page will give you information on the quantity of water (or another liquid) and caustic soda to use. The Sage gives a bracket of water amounts that can be used; to begin with, I recommend calculating and using the average. Here: between 70 and 105 ml ---> 86 ml or grams.
***
Using caustic soda: the online calculators
  • The lye table gives you the quantity of soda you must use depending on the excess fat/superfat you want. The more superfat you want the soap to be, the less lye you will use. In other words, you will use a given amount of oil and make a lye reduction. It's just one way to do it (read more about superfatting here).
  • A superfat between 5 % and 8 % is the most common and good enough for the skin. More than 8 %, the soap may not be hard enough and it will make your shower greasy. Less than 5 % is not especially recommended for the skin but for laundry soap, I choose 0 % or 1 % as a safety precaution.

*****
Soapcalc

I use also this other calculator sometimes, just to check (you're never too safe with caustic soda). 

Using caustic soda: the online calculators

  • Again, NaOH (lye for solid soap) is already checked (1 on the picture), and you have to choose a weight measurement (2).
  • The first difference between this calculator and The Sage is that you have to enter the total amount of oil you want to use (it's automatically 500 grams) (2). You choose your oils (5) by clicking on the drop-down menu. Then you fill in each amount either in grams or in percentages (it depends on how you built your recipe).
  • Contrary to The Sage, Soapcalc will give you a precise amount of liquid. In order to get the same average quantity, you have to choose "water as %age of oil" and fill in 30% (3). The automatic choice, 38%, will give you the maximum quantity on The Sage.
  • You also have to choose the fat excess you want (automatically 5%) (4).
  • Once the form is completed, click on "calculate" and "view recipe". You won't get any "brackets" here, only a precise quantity according to the choices you entered.

Labels:

Comments

Post a Comment

Popular posts from this blog

1 - How: the saponification process

0 - Why and how to make your own soap?  1 - How: the saponification process    Soap is the result of a chemical reaction between fatty substances (oils, lard, vegetable butter) and sodium hydroxide also called lye or caustic soda (NaOH). Caustic soda is a dangerous substance and is to be used very carefully, but it is totally transformed through the process: none of it remains at the end of the chemical reaction...if you used the right quantity of lye. If you use more lye than required your soap will be "caustic" and irritating. Therefore it's recommended that you use less soda and more oil than the exact amount required for total saponification. Firstly, it's a safety precaution: using more oil than necessary for the chemical reaction is a guarantee that the lye will be entirely transformed through the process. And more than that, with extra oil (nonsaponified - remaining oil), your soap will be even softer on the skin. This extra oil is called "sup
1 comment
Read more

Eco-take care of your skin, that's easy & cheap

Oil is your best friend! (see below) Are you sick of using creams you don't understand half of the ingredients (usually not a good sign), and which your skin does not seem to appreciate? Here are easy solutions to replace them. You can first decide to buy organic cosmetics, but since it's rather expensive I understand why many people give up. But at least you know that stuff you put on your skin are healthy.  You can also decide to make your own cosmetics yourself ; it is not that hard to find raw material but it doesn't mean it's easy to to make a high quality cream. That requires knowledge on your type of skin, on the ingredients you use, on chemistry (a cream is an emulsion) and on hygiene precautions. The great advantage is that you know exactly what's in it and choose the ingredients according to what you really need. On this blog I will only speak of easy stuff to make, like lip balm for example. But as regards skin care, I like simplicity, wh
7 comments
Read more

How to recycle a fleece jacket?

Fleece is a very useful material and there are many things you can turn an old jacket into, like make up pads ( see previous article ), baby wipes, dusters and so on. Every piece of fleece is reusable, so the first step is to remove all the threads. It's even more interesting because where the fleece was folded (hemline) or inside the pocket, the fabric has remained very soft, perfect to use on the skin. I think, other parts, more "exposed" are still soft enough. You might see the different textures by clicking on the picture. Once the fleece is ready, there is nothing easier: you just have to cut the shape you want, and it's done. Small squares for facial pad s, bigger pieces for baby wipes ...or duster . I didn't expect it the first time I tried but fleece is a very efficient dust catcher. As efficient, maybe more than microfiber cloth . That's why I use it to clean the floor too. I cut a long rectangle so I can tie it on my specia
3 comments
Read more