Cold process dual lye soap

[Bazz_74]

Hello, i've made a all sodium hydroxide cold process soap and that turned out fine, recently i tried a dual lye soap using cold process and it hasn't hardened up. The ratio was 60% Potassium hydroxide and 40% sodium hydroxide and i used a 5:1 water/lye ratio.

Should this harden up eventually? and if not can i still cook it several days later and just go hot process?

Thanks.

 

[IrishLass]

Hi Bazz! Potassium hydroxide is primarily used for making soft soap, so your dual lye soap won't ever become as hard as a 100% sodium hydroxide soap would (whether it's made via CP or HP). I myself make a dual lye shave soap. Presently my hubby's favorite ratio for me to use is 80% KOH and 20% NaOH, but I've made several batches with 60% KOH and 40% NaOH. Eventually, they do get harder over time, but they in no way ever get as rock hard as my 100% NaOH soaps.

I noticed you used a 5:1 water to lye ratio. That's a pretty high water amount. You can be sure that that's contributing to the overall softness right now. You can definitely HP it if you desire in order to evaporate some of that water off.


IrishLass

 

[Bazz_74]

Thanks for your reply, i may give it time, i'm in no rush and see how it goes. Next time a might go for a more sodium heavy soap.

 

[artemis]

I thought that a small amount of KOH could make the soap harder? I think there was quite a lengthy thread on the subject a while back. Did you try searching the forum for dual lye soap?

 

[DeeAnna]

Compared to 100% NaOH, adding KOH to the lye solution will increase the solubility of the soap. A little bit -- maybe 5% KOH up to 10% max -- will make the soap lather better without noticeably softening the soap. If you add more KOH, however, the soap will become noticeably soft. Doesn't matter whether you use a hot or cold process method. Potassium soaps are naturally soft.

A 60:40 blend of KOH:NaOH is an alkali blend that I would normally use for making shave soap. This type of soap is supposed to be softer and more soluble in order to lather easily and abundantly.

I've left a 100% KOH soap out in the open for months to dry. Although the soap is no longer sticky after drying for so long, I can still deform the soap easily by hand. The same soap made with 5% KOH or zero KOH would be hard and impossible to crush.

That's a lot of water in this recipe -- 5:1 water:lye ratio is only 16% lye concentration. That is also going to contribute to initial softness and a lot of warping and deformation.

 

[Bazz_74]

Compared to 100% NaOH, adding KOH to the lye solution will increase the solubility of the soap. A little bit -- maybe 5% KOH up to 10% max -- will make the soap lather better without noticeably softening the soap. If you add more KOH, however, the soap will become noticeably soft. Doesn't matter whether you use a hot or cold process method. Potassium soaps are naturally soft.

A 60:40 blend of KOH:NaOH is an alkali blend that I would normally use for making shave soap. This type of soap is supposed to be softer and more soluble in order to lather easily and abundantly.

I've left a 100% KOH soap out in the open for months to dry. Although the soap is no longer sticky after drying for so long, I can still deform the soap easily by hand. The same soap made with 5% KOH or zero KOH would be hard and impossible to crush.

That's a lot of water in this recipe -- 5:1 water:lye ratio is only 16% lye concentration. That is also going to contribute to initial softness and a lot of warping and deformation.

Thanks for sharing your knowledge, this is a shave soap, and the first i've made. I expect it will be usable but i was hoping for a harder soap, being a newbie i just picked up on a few bits from online articles. You live and you learn eh!