Lye Calculator - Saponification 1.1

DISCLAIMER: This is provided as is. Lye is a dangerous substance, and though every effort has been made to ensure that the values calculated are correct you are using this at your own risk.

This is a lye calculator for making soap. Its use is simple.
Simply download and unzip the file sap_1_1.zip to a directory on your harddrive and run saponification.exe.

1. You will be presented with a dialog box like this.
   
2. Select the type of lye you are using: Sodium Hydroxide or Potassium Hydroxide. Sodium Hydroxide will make solid soap, and potassium hydroxide will make liquid soap.
3. Select the unit of weight, ounces or grams.
4. Next add the fat or oil you would like to use by clicking the add button or double click in the grid.
5. Select the type of oil or fat you want to add.
   
6. Enter the amount of fat in the edit box.
   
7. If the fat or oil you want is not listed, you can add it by choosing custom and filling in the name and SAP value. For Corn Oil it is a 0.136, but if you call an oil supplier that will probably tell you 191. They are giving you the scientifically defined sap value which is the number of milligrams of potassium hydroxide needed to completely saponifiy 1 gram of fat (in this case corn oil). When you enter the number and hit ok, the program will present you with a dialog and verify the type of sap value (KOH or NaOH).
   
   Make sure you know what you are doing when you enter in the saponification value for a fat or oil. The wrong number can make you put too much lye in your soap and cause burns.
    
   
   
8. If we go back and look at Corn Oil3 we can see that the sap value was converted.
   
9. Hit ok. If you selected a custom fat, it will be remembered the next time you add a fat, and saved to the file sap.txt.
10. Once you have your fats selected the amount of lye needed will be shown from 0% excess fat to 10% excess fat. The X% excess fat is the amount of fat (by percent) that is not saponified in the process. It is good to have a little extra fat in the soap for two reasons: 1) it ensures that all the lye is used up, and 2) it ensures that all the lye is used up. If you have excess lye in your soap the soap will burn you. Unless you have precision equipment for measuring fat and lye (you don't), you should use 5% or greater. Most home soap makers use between 5% and 8% excess fat.
11. You will also see a calculation that shows you the amount of water to use.
    
12. Lastly you will see a combined weight of all the ingredients. This will give you a rough estimate of the final weight of your soap, some of the water will evaporate.
13. Once you are satisfied with your recipe you can save it by pressing the save button. You will be presented with a dialog box, and can type in the name of a new file or select an existing file. If you select an existing file you will be prompted to make sure that you want to overwrite it.
14. To load a recipe simply click the load button, and select the file.

Copyright 2003 Dudley Fox All rights reserved.

Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:

Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.