Soda ash and oven process

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Hey everyone! I’m sure there is a lost about this somewhere but I need some advice. So I really started oven processing all of my soaps for the beautiful bright colors it gives me. I have a couple issues I can’t seem to put my finger on. I use full water mostly and pop em in the oven at 170. Sometimes i will leave the oven on for 30 minutes and then shut it off or shut it off right as i put it in. The problem i see are a couple. Sometimes my fragrance will bead out or i still get ash days later. I guess I was wondering really if I should let my soap sit to harden up quite a bit and then go in the oven or try something else to prevent ash. Using distilled water only.
 

earlene

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When you say 'full water' are you meaning you use the default setting on whatever calculator you use and the default is 38% water as % of oils? If that is the case, I would say that you may be using more water than you need and that is contributing to the soda ash problem. Try changing your setting to lye concentration or water to lye ratio and use less water, while continuing with CPOP. This can reduce soda ash.

Depending on your recipe, of course, I would suggest moving to a 30 to 33% Lye Concentration. Perhaps you could share the specific recipe to help with trouble shooting. But for the sake of presenting you with an example of how that is done, here is a Castile soap recipe (500 grams of oils) showing the different amounts of water for 3 different settings:


Default 38% water to oil = 25.3% Lye Concentrtion = 2.9 : 1 Liquid to Lye ratio. That's a lot of water.

1652785814636.png



Try this: Change the setting to Lye Concentration & set it at, say 32%. Notice the difference in the amount of water used when that is the only change?

1652786149551.png




Or try 2:1 Water to Lye Ratio. Again, this alters the amount of water used.

1652786376107.png



Many soapmakers who prefer to use either Lye Concentration or Liquid : Lye ratio as their usual setting, in order to get more consistent results across different soap recipes.


There are several threads here at SMF that explain how soda ash forms, so I won't go into that. A search can pull up results to give you a lot more detail of the how & why of soda ash. This is just to show you a method that will help you get consistent results by using less water in your recipe.

Some also find spraying alcohol on top of the soap prior to covering it, but others don't like the pitting on top of the soap that they get with the alcohol droplets. A very fine misting sprayer can be a way to prevent the pitting, but even without spraying alcohol, reducing water in the recipe goes a long way to preventing soda ash.
 

Zany_in_CO

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Sometimes my fragrance will bead out or i still get ash days later. I guess I was wondering really if I should let my soap sit to harden up quite a bit and then go in the oven or try something else to prevent ash.
In addition to @earlene's excellent advice, don't rush through making the batch. I've noticed that "fragrance beading" happens when the batch isn't thoroughly stirred after adding scent. If you're not already doing this, try adding it your warmed oils and stirring for one full minute before adding the lye solution.

It's best to oven process sooner rather than later, while the batch is going into gel, so I would not allow it to harden up before putting it in the oven. On the other hand, if you simply cover and insulate the batch with towels or old blankets and put it "to bed" you may find that you don't need to OP it.

There have been SO many discussions about preventing ash but I can't help you there. In all my years (since 2003) I've never had the problem. And, Old School here ;) , I do use full water sometimes, depending on what's in the recipe. I also use lye concentration or lye to water ratio for some batches. It all depends on what works best -- you only learn that with experience over time.

I also put ROE and Vitamin E in every batch.

I do use temps 100°-120°F for recipes high in olive oil or other liquid oils; 120°-135°F for recipes high in hard oils. I don't spray with alcohol, but I do cover every batch with 4-ply mylar before insulating to insure full gel.

You might check out @DeeAnna 's Soapy Stuff to learn more about preventing ash.
 
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Thanks for the response so quickly! Right now I have to go to work but I will share my recipe later today. When I say full water yes I mean what the calculator gave me when I tweaked this recipe a couple years ago. I have noticed the masculine or earthy fragrances are my biggest culprits. Dragons Blood is the worst ashing halfway into my soap. Doesn’t matter the manufacturer. However my melon mist did too but not very bad. I could steam it off. I have to make a batch tonight for a client so I will discount water and give it a whirl.

I will be back this evening with my recipe and gather thoughts. Thanks again!
 

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