Shaving soap problem

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user 28270

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My basic recipe is:
Stearic Acid 40%
Tallow 30%
Butters 18%
Castor/Coconut oils 12%

I’m using KOH for the stearic and NaOH for the rest. I combine them after the lye has done its job. I do add glycerin (15%) and sodium lactate during the cook. I have a number of additives added after.

The problem is that once it cools down enough to add the fragrance, or even close to it, it starts to harden too quickly and I can’t get it into the jars without it turning into a horrible looking mess.

I’m expecting to be able to scoop an amount into the jar and tap the jar on the counter to get it to settle nicely. But it’s not doing that.

Would a higher water content help? Any other ideas?
 
With that much SA it's never going to be easy to work with and getting pretty sides in a glass container is, in MYO, almost impossible. There always seems to be some air bubbles on the sides that you can't get out! That's why I've switched to using small plastic storage bowls that have a lid. I get them from the grocery store. If you mist the top of the hot soap when you scoop it into a bowl you can get a fairly attractive surface. And the lids help to keep the scent from evaporating away while the soap cures. I add my FO's at the same time I combine the two oil mixtures and immediately portion into the bowls and close the lids.

Here is a pic of one of my early testers - I didn't bother smoothing the top as it was for my use. but you get the idea.

IMG_4516.jpg
 
I’m using KOH for the stearic and NaOH for the rest. I combine them after the lye has done its job. I do add glycerin (15%) and sodium lactate during the cook. I have a number of additives added after.

Have you tried making your lye solution with both KOH and NaOH in one solution, adding it to your tallow, butters, and castor/coconut oils, bringing it to trace and then adding your melted stearic acid? This is how I do my shave soap and I have enough play to add glycerine, jojoba oil, and fragrance, and get it into the mold before it become unworkable.
 
Have you tried making your lye solution with both KOH and NaOH in one solution, adding it to your tallow, butters, and castor/coconut oils, bringing it to trace and then adding your melted stearic acid? This is how I do my shave soap and I have enough play to add glycerine, jojoba oil, and fragrance, and get it into the mold before it become unworkable.

I want the soap to have Potassium Stearate, Sodium Tallowate, Sodium ...
If I combine the lyes, I’d have Potasium Stearate and Sodium Stearate, Potassium Tallowate and Sodium Tallowate, etc.
not what I’m trying to accomplish.
 
I don't think you can guarantee the "saponified oils". [Honestly, I don't know what to call that, so that's what I'm going with...]

Here's my reasoning:
The SAP value is an average. Each oil/fat/butter may vary from that SAP value depending on a myriad of conditions, so the SAP calculated for the recipe isn't perfect. The purity of hydroxides also isn't perfect. So even a 0% SF may be minimally lye heavy, or minimally superfatted depending on hydroxide purity, oil/fat/butter quality (which can vary even within the same supplier depending on lots), and of course, human/mechanical error: not having a measurement spot-on perfect or having a scale that is slightly off calibration (I have two scales, both the same brand, and each reads slightly different on the second decimal for the same item).

If I understand your process correctly, you are combining two soaps together after hot processing. Is there a guarantee that both soaps are 100% saponified before combining? I don't think so, even if we cook until there is no zap, I suspect there is still some lye active in the soap and once the two soaps are combined, that lye will latch onto any oil regardless of whether it is in the NaOH soap or the KOH soap.

Is there a reason for wanting to define the saponified oils specifically as Potassium or Sodium? I don't see the value of it as far as the performance of the shave soap is concerned.
 
I don't think you can guarantee the "saponified oils". [Honestly, I don't know what to call that, so that's what I'm going with...]

Here's my reasoning:
The SAP value is an average. Each oil/fat/butter may vary from that SAP value depending on a myriad of conditions, so the SAP calculated for the recipe isn't perfect. The purity of hydroxides also isn't perfect. So even a 0% SF may be minimally lye heavy, or minimally superfatted depending on hydroxide purity, oil/fat/butter quality (which can vary even within the same supplier depending on lots), and of course, human/mechanical error: not having a measurement spot-on perfect or having a scale that is slightly off calibration (I have two scales, both the same brand, and each reads slightly different on the second decimal for the same item).

If I understand your process correctly, you are combining two soaps together after hot processing. Is there a guarantee that both soaps are 100% saponified before combining? I don't think so, even if we cook until there is no zap, I suspect there is still some lye active in the soap and once the two soaps are combined, that lye will latch onto any oil regardless of whether it is in the NaOH soap or the KOH soap.

Is there a reason for wanting to define the saponified oils specifically as Potassium or Sodium? I don't see the value of it as far as the performance of the shave soap is concerned.

While the specific saponification cannot be guaranteed, by splitting them apart I can ensure that MOST of the Stearic Acid will end up as Postassium Stearate salts.

As for why, the Potassium Stearate is MUCH more soluable in water then Sodium Stearate and produces a better lather. It also impacts the hardness of the soap.

If Potassium or Sodium salts of anything were the same, why would anyone use dual lyes following your logic?
 
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While the specific saponification cannot be guaranteed, by splitting them apart I can ensure that MOST of the Stearic Acid will end up as Postassium Stearate salts.
"Most" is not all, in which case a label stating Potassium Stearate and not including Sodium Stearate would not be correct. From the perspective of making soap, if "most" is what you're going for, then I feel that combining the hydroxides upfront would still achieve this. But... I've never tried it the way you are so I'm only hypothesizing that the result would be a soap with Potassium Stearate and Sodium Stearate, although those amounts would differ from batch to batch, but there would still be Potassium Stearate.

As for why, the Potassium Stearate is MUCH more soluable in water then Sodium Stearate and produces a better lather. It also impacts the hardness of the soap.
That makes sense, at least how I'm understanding it as "the KOH makes a more soluble and better lather and the NaOH makes a harder soap.

If Potassium or Sodium salts of anything were the same, why would anyone use dual lyes following your logic?
I can't speak for everyone, but I can speak for why I use NaOH in my shave soaps. I use it to make a harder puck that I can put into a log, let harden, and then slice like bar soaps. They're easier to handle, package, and ship. I don't think there's an advantage to the soap performance, at least based on tests that I did when I was playing with the ever popular shave soap thread recipe. I couldn't tell the difference with a dual lye (other than those I've listed for why I do it) in the lather and use.

Combining the hydroxides upfront certainly isn't the only way to do, but it is a suggestion for solving your problem, which was your original question.
 
If I mix the oils, butters and SA and use a 60/40 dual lye, I absolutely have no control over the saponifications and the levels of the resulting postassium and sodium salts can and will vary wildly from batch to batch.
By pulling the SA out with just KOH, and mixing NaOH with the oils\butters till both pass the zap test, while not 100%, will provide a much more consistent resulting fatty acid profile. While there could be some sodium Stearate for example, or potassium Tallowate, the levels would most likely be very low.
As for labeling, the resulting levels may be under 1% and therefore not required, but following common practice, I’d list the unsaponified ingredients.
 

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