Stearic Acid disaster when making shave soap.

[RogueRose]

Well I'm glad I decided to try a small recipe!! I've read in most shaving soap threads that many people use 50% stearic acid, and the rest varies depending upon person. Some to a 50/50 stearic/coconut. My recipe was for 80g oil - 120g final weight:
40% Stearic Acid 32 grams
25% Coconut Oil 20 grams
25% Palm 20 grams
10% Castor 8 grams

As stearic has a melting point of around 140-150 degrees, I mixed all the oils together and heated until about 170 degree. When I poured the hot oils into a metal bowl a layer of cooled oil formed where the oil contacted the bowl. This is like hot wax touching a cold surface - it had the same texture as well (stearic acid is often used in candles, especially tallow/lard candles). I decided to put it back in the pan as it had a thick bottom that retained the heat. This allowed it to stay liquid.

When I mixed the lye water I poured in the middle of the pan and within about 1-2 seconds the mixture started to solidify from the middle out, it almost looked like a volcano, lol:sad:. The only thing that I could think to do was use a whisk and mix as well as possible. I also used a potato masher and pressed the mixture up through the holes in the masher. I did this for about 5 minutes of hard mashing and then scoped into a round pvc mould and then compressed as firmly as possible.

I'm waiting to see how it turned out, but this was the worse reaction I have ever had. Is this normal for stearic acid and can any on give me any pointers on how to make this a little easier to work with?

 

[DeeAnna]

Have you read the shaving soap thread here???? The first page of comments mentions this very thing and many of the comments in later pages discuss ways to handle these issues.

Yes, it's normal for stearic acid (1) to solidify on contact with material that is below its melt temperature and (2) to saponify almost instantly after the lye is added.

 

[lsg]

Did you melt the stearic acid with the palm and coconut oils?

 

[RogueRose]

Did you melt the stearic acid with the palm and coconut oils?

Yes. Was that what should have been done or not?

 

[TVivian]

To make a long thread very short. You have to hot process Stearic acid soaps. Meaning: they have to be cooked over heat.


But when you have some time, read the shaving soap thread. You'll be almost an expert by the end

 

[Dorymae]

Start here: http://www.soapmakingforum.com/showthread.php?t=34264&highlight=Shave+soap

Yes I know it is very long, just start reading it will save you a lot of time, aggravation, and ingredients.

What happened to you is completely normal. Stearic acid can be difficult to work will in HP soap, but it is nearly impossible in CP.

Read, read, read. . . You won't be sorry.

 

[Seawolfe]

+1 on reading the shaving soap thread.

Per DeeAnna's suggestion, I heat the stearic separately, that way I don't have to overheat the other oils. Stearic is a big pain to work with! It makes that horrid film and seizes the soap. I've only ever used it with a combo of NaOH/KOH, I can't imagine how it would seize with just NaOH, and without heat it would be impossible I imagine. I now have 1 plastic bucket just for melting stearic, so it can keep that nasty film to itself.

 

[lsg]

I have always hot processed the soap in which stearic acid was an ingredient. I use an old crockpot. Even if the soap seems to sieze, it will loosen up as it heats and you can remix with a stick blender, if needed.