do this while children are asleep or not at home. use caution, gloves, and goggles:
1. line a soda or water bottle box (about 2ft x 1ft and 4 inches deep, exact measurements not important) with a trash can liner. you can just put the whole box inside the bag then pat it down so you can easily pour the soap in once you have made it. if needed, you can reinforce the box with packaging tape to make it more sturdy.
2. make a "nest" of towels, blankets, etc and put your prepared soap box on top and in the middle. you will be using the nest to insulate the box. prepared castille soap is difficult to move in the first day so put this all in a safe warm place where your kids can't get to it. have a second trash bag next to your nest.
3. in a large non-corrosive pot measure 140 ounces of olive oil (costco and sam's club sell 5 litre bottles for about $25) and warm to about 100 degrees (like a warm bath). if you are scenting your soap you will need to be more precise, but for basic soap it is not vital.
4. in a large plastic pitcher measure out 5 cups of cold or room temperature water. filtered is best but tap is usually okay. to this water slowly add the entire 18 oz of
red devil lye. this is the standard size available at many grocery/hardware/department stores. the fumes are a bit overwhelming, don't breathe them in directly. you can mix it outside but if you do be very careful carrying the lye inside. continue stirring until the mixture is clear. (if you are stirring with a wooden spoon use one that you can throw away when you are finished.)
5. slowly pour lye solution into warm oils. the lye solution is HOT and CAUSTIC. use caution!!! if any of it gets on you rinse immediately and thoroughly.
6. mix with a stick blender on low using figure eight motions being sure to go up and down the entire solution but being careful not to lift the blender above the surface of the soap solution. doing so will force air into your soap.
7. continue mixing. the solution will first become cloudy, then yellow. continue until it looks like vanilla pudding right before it is poured.
8. pour uniform solution into prepared box. cover with your second trash can liner. wrap nest around your box and leave it alone for a few days.
9. after several days cut it into desired shapes and let dry for a few weeks. you can use it after a week or so, but the full curing time allows the excess water to evaporate.
10. clean up all supplies immediately, before removing your gloves and goggles. remember to clean under the blades of your stick blender. i find it helpful to "mix" hot water with the stick blender plugged in to help in this step. if you are wiping with cloth be sure to toss those in the washer immediately. fresh soap is caustic and will burn you. if you used a wooden spoon dispose of it after rinsing excess off.
this will yield about 12-14 lbs of soap after accounting for waste and excess left in the pan. i would guess that is equivalant to about 50 standard size bars of soap.
hth

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