Dual lye question

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Wsp, can you be a bit more specific? Are you looking at branching out to shaving creams and wondering about a mix of KOH and NaOH?

If so, what is it about the mix that appeals?

I am, but that's not the heart of the question.

Liquid soap makers sometimes use a mix of NAOH & KOH. And the question pops up sometimes in the FB group.

I'm just wondering why they want to do it. From my research, it acts as a thickener. From my experience with shaving, people rave about dual lye soaps. However, there's not exactly the exact same formula to test this dual lye is better proposition.

Therefore, I am now wondering if there is a benefit (other than thickening) to making liquid soap with dual lyes.
 
Interesting. Have you made the same recipe shaving soap, one with mixed lye and the other pure KOH? Is it the recipe of the soap itself that is well liked, and a mere chance that both lyes are used?

When I made test batches for that, I found that the loading was different, but when both were dialed in they were comparable.

So far, no one here has really spoken of using a mixed lye for a liquid soap to make it thicker - using a little bit of NaOH soap as a kick-starter, yes, but nothing more. I am not an experienced LSer, so I do wonder what the collective wisdom has on that.
 
I would think Wsp would know and have had tested his shaving soaps every which way, since they are sold on Amazon. Sorry guess I am being a little catty today. After testing and playing with shave soaps for 2 years I still do not feel qualified to sell them But I also want to check into challenge testing my soft shave lotion. Mine is made with dual lye and lathers fantastic
 
I have made liquid soap with dual lyes up to the 60/40 mark. There is no appreciable thickening.

I used to use dual lyes because NaOH is LOTS cheaper than KOH, and I wanted to know if it changed anything. It only changes the cost, IMHO.
 
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I haven't used both lyes in LS making, but I have used both in cream soap and shave soap. Other soapers who have tried NaOH in their liquid soap report roughly the same thing as Susie -- the thickening is underwhelming.

I think there may be more benefit to adding a bit of KOH to a bar (NaOH) soap than vice versa. The KOH will increase the water solubility of a bar soap. If your soap is high in the low-solubility fatty acids such as stearic and palmitic -- for example a high lard, high butter, or high tallow soap -- then a small % of KOH can make this type of soap lather more easily. If I remember correctly, Sistrum, a former participant here on SMF, used about 20% KOH in her bar soap. She preferred high lard recipes, so that makes sense.

And that gets us back to why shave soap often has KOH in it. :) And gets me back to my perception that the various types of soaps -- bar, liquid, cream, etc. are all variations on a main theme. Each has its quirks, certainly, but they not totally separate types of soap.
 
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Interesting. Have you made the same recipe shaving soap, one with mixed lye and the other pure KOH? Is it the recipe of the soap itself that is well liked, and a mere chance that both lyes are used?

That's what I'm working on currently. Whether the dual lye imparts the benefit, or if the sodium hydroxide is there for other reasons. I'm kind of leaning towards the hypothesis that the NAOH is only there for hardness.

What I'm referring to are B&Bers love of dual lye soaps like Tabac and similar. There may be some wisdom in their praise of the dual lye soaps. But, who knows.


I have made liquid soap with dual lyes up to the 60/40 mark. There is no appreciable thickening.

I used to use dual lyes because NaOH is LOTS cheaper than KOH, and I wanted to know if it changed anything. It only changes the cost, IMHO.

Oh, well that makes a hell of a lot more sense. Really explains why all these FB liquid soap people want to use NAOH. The cost difference to me is only .20 per pound. Pretty negligible; but more KOH by weight is required to saponify the same amount of oils.

I haven't used both lyes in LS making, but I have used both in cream soap and shave soap. Other soapers who have tried NaOH in their liquid soap report roughly the same thing as Susie -- the thickening is underwhelming.

I think there may be more benefit to adding a bit of KOH to a bar (NaOH) soap than vice versa. The KOH will increase the water solubility of a bar soap. If your soap is high in the low-solubility fatty acids such as stearic and palmitic -- for example a high lard, high butter, or high tallow soap -- then a small % of KOH can make this type of soap lather more easily. If I remember correctly, Sistrum, a former participant here on SMF, used about 20% KOH in her bar soap. She preferred high lard recipes, so that makes sense.

And that gets us back to why shave soap often has KOH in it. :) And gets me back to my perception that the various types of soaps -- bar, liquid, cream, etc. are all variations on a main theme. Each has its quirks, certainly, but they not totally separate types of soap.

I've done that for my mechanic's soap recipe. Really helps lather ability.

Yeah, I'm really leaning towards the no real benefit from dual lye for liquid or shaving soap. In terms of performance anyway.
 
I am still just a hobby soaper, so my KOH comes in 2 lb bottles from ED, and shipping is what kills my budget. However, with our humidity(the climate here is just like in Louisiana), I am afraid to buy larger quantities.
 
I've got tons of KOH lying around, so I've been playing with liquid soap lately. ;)


I know that Lee (lbussy) is a fan of KOH only shaving soaps. I would make two little batches of the same recipe but with mixed and KOH only - as I said, they load differently but I haven't done enough testing to say that one is better than the other.

Edit to add - there was a thread about using mixed keys - I can't really find it as I'm on the app, though.
 
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