Help Needed re Soap Calculators

cooksonscharlie · Apr 7, 2016

I was reading Irish Lass's entry from 2014 which sets out a method for GLS. It gives % of 65 for OO, 25 for Coconut oil and 10 for Castor oil. This much is straight forwards. I then went to see how much KOH I should be using. I checked with manufacturer and KOH I bought is definitely 90% concentration
As I'm new I tried 325g of OO, 125 of CCO and 50g of CO. 3% super fat.

Soapcalc says. 110g of KOH and 190g of water
The Sage MMS says 99.92g ofKOH for 3% superfat and between 125 - 188g of water
Summers Beemeadow 105.18g of KOH and over 315g of water

The Sage MMS does not give any choice for concentration of KOH used but the other two do. Is my maths totally to pot? Which would you follow - Soapcalc or Summers Bee meadow? 5g seems quite a big difference KOH and the water difference is colossal. Can anyone explain what I'm doing wrong. I'm sure I'm being thick but just can't get it!! I'd be grateful for your help. Thanks

Susie · Apr 7, 2016

Just pick your favorite calculator and stick with it. The difference is that each calculator is using different SAP values for the oils. Being that there is 10 g or less difference, all can yield a successful batch of soap. Just pick a calculator and stick with it, so that as you change the lye discount (AKA superfat, although that is a misnomer), you will be able to know which one you prefer.

I, as well as IL, prefer to use a 1:3 ratio of KOH:water. It yields a paste that is easier to work with. For this reason, I prefer SBM or Soapee.com for liquid soap recipes.

DeeAnna · Apr 7, 2016

Summerbee and Brambleberry assume about 94-95% KOH purity. Soapcalc is your best bet if you want a calc that lets you choose 90% purity. MMS and most other calcs assumes 100% KOH purity if memory serves me. These assumptions are probably most of the differences in lye weight that you're seeing. Minor differences in sap value, as Susie mentioned, will also cause small differences from calc to calc.

I second what Susie said about water content -- I use a 3:1 ratio of water to lye as well. If you prefer to use lye concentration rather than water:lye ratio, you'll get the same answers for water if you set the lye concentration to 25% -- that means the same thing as 3:1 water:lye ratio.

IrishLass · Apr 7, 2016

Ditto what Susie and DeeAnna said.

When I first started making liquid soaps, I had no idea what the purity of my KOH was, and had no way of finding out because by the time I finally got up the courage to make that first batch, the company I bought it from had gone out of business when the owner died.

I chose to use SummerbeeMeadows Advanced Lye Calculator because that was the one recommended to me by my liquid soap mentors on another forum. And it was the one they chose to use because the calculator happened to be made by experienced liquid soapmakers for fellow liquid soapmakers, and also because of how their liquid soap turned out when using it in comparison to how things turned out when using some of the other soap calculators.

The way they talked about it, SBM's SAP#'s and their default water level of 1 part lye to 3 parts water (a 25% lye concentration) seemed to make things work like a charm for them, so that's the one I went with for my first batch, and it's the one I've always stuck with......and not once have I ever been sorry that I did.

SBM's default water amount might seem like a lot in comparison to what other calculators have as their set/default water amount, but it's truly a perfect water amount for liquid soap if you ask me......and Susie and DeeAnna and countless others, too, lol.

IrishLass

cooksonscharlie · Apr 8, 2016

Thank you all three. Brilliant explanations. Knowledge is everything!! I came across the differences by chance (Trying to be super careful!) as my LIquid soap so far has not been the brilliant. So helpful. Will get on and make it this weekend! Thanks.

Susie · Apr 8, 2016

You would really benefit from reading this thread:

http://www.soapmakingforum.com/showthread.php?t=46114

There is a LOT of good discussion about making liquid soap. And a wonderful tutorial by IrishLass.