Glycerin...What Are The Rules?

[Jetpilot]

I’d like to add glycerin to my next shave soap recipe. It’s obviously unsaponafiable so no reason to calculate lye. The soap calculator tells us how much liquid to add. If adding glycerin do I subtract if from the total liquid required? Can you totally eliminate water and add just glycerin for the lye solution? Is there a rule for the maximum amount of glycerin I should add? Thanks in advance!

 

[lsg]

Yes you can use all glycerin; but many prefer to use part water to dissolve the lye and add glycerin later. If you do use all glycerin, heat the glycerin to dissolve lye. Here is a tutorial on using glycerin instead of water for liquid soap.

 

[The Efficacious Gentleman]

Depending on how much pure stearic I use, I add around 15% of oil weight as glycerine when using 50% stearic. I don't consider it part of the liquid