Advice for shaving soap

[alaskazimm]

I've read through Songwind's thread and have made a couple batches of that. It's very well received by my shaving friends, but I can't use that recipe myself. In about the middle of the first pass my face begins to tingle as if it's reacting to something in the formula. Happens with both scented and unscented.

Long story short, I want to develop my own formula and after kicking around for a bit I came up with a cream type soap using a 4:1 of NaOH:KOH. I've read that shaving soap needs anywhere between 20 - 40% stearic acid content. Using mostly beef tallow, I got to a total stearic acid of 21% (I didn't have any straight stearic acid on hand to boost the total). It lathers very nicely with just an almond size scoop, is decently slick and thick.

Here's the problem, if left to sit on its own (or even on my face) the outer layer quickly dries to a crusty looking outer shell. A quick swirl of the brush seems to restore it again but only for a minute or so. Is this a lack of stearic acid content? Or is something else in play here?

The recipe:

beef tallow 47.1%
shea butter 16.5%
castor 16.5%
coco butter 10.6%
avocado 9.4%
after cook:
1 tbsp bentonite to 1 lb oil
10% glycerin (42 gr)

 

[grayceworks]

Its fine for the outer layer to dry between uses. Its a good thing. You don't want water sitting in there and growing germs. as you have seen, a quick swipe of a wet brush is plenty to get it lathered up again.

Also, did you check for zap on the batches that bothered your face?

Or it may be that you're sensitive to CO.

I wouldn't lower the stearic toooo much though. Did you put stearic acid in the recipe you just posted? If so, I'm confused, as it should, including the stearic acid, add up to 100%, but that recipe just your oils alone add up to that with no room for stearic acid.

I have done 48% stearic acid, 25% some hard oil, 12% shea, 8% castor, 7% some other nice conditioning oil, with a 7% SF and 2T ppo of glycerin and .5tsp ppo bentonite clay very well dissolved in a bit of water. It made a very nice recipe when I did it with CO and jojoba, and I'm thinking of trying lard or tallow as well...

I am worried that the amount of clay ppo might be drying? I have only ever used it at .5tsp ppo, but maybe someone with more experience with clays can chime in?

ETA - is that stearic number based on just the stearic content of the oils? If so, that may a big part of where you're having trouble with your recipe. It should have, if you're using songwind's as a starting point, actual stearic acid figured in as if was any other oil. There is a listing for it in soapcalc and it is a very inexpensive ingredient to buy, well worth it!

I'm thinking also, based on other's posting about their experiences with KOH to NaOH ratios, that for a creamier soap, it should be higher in KOH, rather than NaOH. Might also contribute to how quick it's drying out on you. Because I just went and played with mine, and it stays creamy for quite a bit, but is dry on top again after an hour or so. Inside the soap stays about the consistency of putty or play-doh.

 

[alaskazimm]

Thanks!
Yeah, I meant the 21% stearic acid content was just from what is naturally in the tallow and butters without any extra added. On the artisan shave soaps I use some add stearic acid, others don't.
Also, I got the KOH and NaOH backwards - 4 KOH:1 NaOH. So all good there.
The lather dries too quickly on the outside while shaving, which is not a good thing and maybe that's from being too low on the stearic content.
And maybe I used too much bentonite since it turned a rather unappealing grey shade.


I think you're right on the tingle/prickle I feel from songwind's is a sensitivity to high percentage of coconut(?) as I get something similar from shave soaps that are scented with coconut. Which is kind of strange since I can eat food made with coconut oil with no problem.

 

[grayceworks]

Try using actual stearic acid for a large portion of your recipe and subbing the CO with tallow then, and yeah if it turned all grey, it's probably s bit heavy on the clay

This type of recipe is really fun to play with since it's quick and also ready quick. But! It STILL benefits from at least a couple weeks cure, if not more... You might try your CO version again after a month or more and see if you still get irritated by it...

 

[jeffegg2]

I've had this happen with commercial shaving soaps... have you tried adding more water to your lather???

Also... how did you compute the lye using the 4:1? I have not seen soap calcs that will use a combination?

Jeff.

 

[alaskazimm]

I did try more water but then it became too wet and actually dissipated faster. I think it probably was that the stearic acid percentage was too low - in the 21% rather than 40%+ that is ideal.
To compute the lye I use Soapmaker and the option for cream soap.

 

[alaskazimm]

Update on the great shaving soap experiment: I took my recipe above and kind of mashed it together with Songwind's. I dropped the coconut oil completely as I think I have a sensitivity to high amounts and substituted tallow. I dropped the %'s of both tallow and stearic acid while adding in some conditioning oils and butters, and reduced the clay to 1/2 tsp ppo. The KOH and NaOH stayed at 4:1. With this mixture the stearic acid content was mind 40's.

It ended up as a cream but wow! so much better - lathered easily although it needs a lot of water. Thick, slick, and great feel on the face. Best of all no prickly feeling!

I'm trying again with a slightly different recipe and a KOH/NaOH ratio of 2/1 to try to get more of a croap than a cream. I think I'm getting closer