Soap/Lye Calculators; A guide

[Sue Bear]

I use Soapmaker now but for my first 9 months of soaping I used the calculators on Wholesale Supplies Plus. I found them easy to use and very helpful.

Percentage Calculator: http://www.wholesalesuppliesplus.com/Ca ... lator.aspx

Batch Calculator: http://www.wholesalesuppliesplus.com/Ca ... lator.aspx

Lye Calculator: http://www.wholesalesuppliesplus.com/Ca ... alcWP.aspx

 

[TopRock]

Not sure if this has been asked before (I apologized if it has);

Do lye calculators give you the water needed in fluid ounces or weight ounces? I know that the measurement either way is ver similar but when dealing with larger batches it is a difference. Thanks!

 

[Hazel]

The amounts on lye calculators are for weight. Always weigh the ingredients because it's more accurate.

 

[TopRock]

Thanks Hazel! I have seen people referring to FL ounces when it comes to specicialty soaps like beer and coffee so I was just making sure.

 

[Hazel]

You're welcome. I wish all questions were as easy to answer.

 

[danahuff]

My two favorite lye calculators are Bramble Berry's and Natural Soap Boutique's. I check out several, and I notice that the results are always slightly different, but never by a whole lot, and I have had good results with these two calculators.

 

[Hazel]

It's really personal preference on what calculator you like. I dislike Brambleberry's calc because I have to re-enter everything if I want to go back and change percentages. Plus you have to remember to change the SF from 0% to whatever you percentage you want. I know people in the past have asked for help and it was found they had forgotten to change the percentage. Whereas with SoapCalc, it opens the recipe into a new tab and I can easily change percentages if I'd like to see a variation. I can do this several times and click the back button to return to a recipe page if I decide I'd rather print off a previous variation. SoapCalc has a 5% default SF so you don't end up with a lye heavy batch if you do forget to change it.

I've never seen the other lye calc you mentioned but I went and looked at it. Interesting. It looks like a blend of SoapCalc and Soapmaker in the way it's set up. I entered a recipe to see how it worked and wasn't impressed. It has a limited amount of oils and butters compared to SoapCalc. I also didn't like how the oils are listed non-alphabetically but I guess if you got used to using it that wouldn't be so annoying. Also, there isn't any way to change the SF and according to the site it's supposed to calculate a 5% SF. The amount of lye it showed would be -1 according to SoapCalc. I decided to try the same recipe on Brambleberry. You can't figure a minus SF level on Brambleberry. It stops at 0%. However, the amount this site recommends is still .8 oz more than BB gives for a 0% SF which would make approximately a -3% difference in the SF level. Of course, I'm not very good at calculations and I could have figured this wrong. But I'd say it's highly probable the batch would be lye heavy. I did notice the difference for a 5% on BB as compared to this other site was 1 oz. According to BB's calculations, 1 oz of lye is enough to take the SF percentage from 0% up to 10%. In my opinion, that's more than a slight difference. However, I only checked one recipe on all of them.

But as I said above, it's personal preference. How many batches have you made using this calc and how did they turn out?

 

[danahuff]

I have made a few batches, and they all turned out well. None of them were lye heavy, and they made nice bars. I know what you mean about forgetting to make changes to the Bramble Berry calculator. That is annoying, and I've done it, too, but again, my soap has turned out nice when I have been careful about checking all the numbers. I have come to prefer Bramble Berry because, as you said, the variety of oils is greater. I just found out about SoapCalc and have been running my recipes through them just to check and found the Bramble Berry calculator's numbers were more similar to SoapCalc's. It may seem weird, but one reason I like the other one is that when I run a recipe and hit print, it gives me predictions about how the bar will turn out. I don't rely on it so much for calculations as I do to see what it says about the recipe. For example, here is a prediction for a recipe I use a lot:

* INS: 160
* Hardness: medium
* Cleansing: very good
* Conditioning: great
* Foaming: good
* Stable lather: average

That is easier for me, as a newbie, to wrap my head around than figuring out what it means if numbers are high in Lauric or Oleic acid. If I run my favorite recipe through the Natural Soap Boutique calculator, it asks for 5.7 oz. of lye, 13.3 oz. water. The same recipe in Bramble Berry asks for 5.637 oz. lye, 13.2 oz water. SoapCalc figures the same recipe needs 5.691 oz. lye and 13.2 oz. water. The difference could be that the Natural Soap Boutique calculator doesn't allow you to use tenths. You are limited to whole numbers, which I agree, is a real problem with that calculator. But at least with that one recipe, I wasn't seeing a whole lot of difference in the amount of lye and water needed. I haven't run a lot of recipes through the calculators, though, so it could vary widely, I suppose, based on what you are using and how much and certainly whether you have it down to tenths of an ounce.

 

[Hazel]

I'd still recommend using extra caution with that calculator and double check the lye amounts. I rarely use 5% SF so I wouldn't use it even if I thought the lye amount was okay. I prefer being able to adjust the SF to allow for extra conditioning, if I'm using cream or if I'm making a salt batch.

 

[danahuff]

Hazel, none of the soaps I made with that calculator have turned out bad, but I have stopped using it. The more I use SoapCalc, the more I realize it is clearly superior to the other calculators. I really like that it gives weights in grams, ounces, and pounds, though I'm not sure I'd ever make a batch big enough to worry with pounds. I also like that it allows you to easily change and tweak until you're happy. I have come to worry about the other calculator now that I realize how precise you need to be when working with small batches. I don't think I'll ever use it again. I also find it worrisome that it will not allow for tenths of an ounce. Anyone coming by here, please don't use that calculator! I wouldn't use it anymore, and I don't endorse it.

 

[sueforce]

Just joined so apologies if this lands in the wrong place!

I have been making CP soaps for about 2 yrs - really concerned about the lye calculators - as far as I can see none of them state original sources for SAPS - so where have they come from? How accurate are they given that all oils have a fatty acid composition that presumably reflects the source material, growing conditions and seasonal variation and that suppliers will comply with a set of specifications that stipulate a range of values for each particular fatty acid?

The only answer I have had to my question is 'based on traditional values from years ago' - but things have changed.

Does anyone else have any comment or answers re source for SAPs?

Sue

 

[sueforce]

And how can this be explained: I met a CP soapmaker who had been using 20% too much NaOH / lye for years without any problems. Selling well, lots of exposure. No 'burning' or ashing or signs of unprocessed NaOH The recipe used 30% sunflower oil, very rich in polyunsaturates, did that have an impact? PH fine and measured using an ISO rated pH meter (mine).

But - mixing was v good I suspect, probably very homogeneous - is this more important than lye content?

I would be really interested in any comments on this.

Sue

 

[squigglz]

Putting this here because I couldn't find it elsewhere and I personally want to know how to do it by hand in case I lose internet for any reason:

http://www.certified-lye.com/lye-soap.html

That'll show you the equations you need and whatnot to calculate this out by hand.

 

[justinwp]

I have a new web based calculator in the works. It's a little more modern and responsive with charts! I still need to do the styling... (See the screenshot)
- PM me if you would like to beta test it.
- PM me if you have javascript, jquery, php, mysql skills and would like to help in the development?

Some of the existing features:
- Properties and Lye/Water calculations are instant
- Ability to see how your recipe compares to others with charts.
- Liquid/Bar/Custom mix between NaOH or KOH
- Instantly switch between units
- Instantly change batch size without leaving the page
- Ingredients are sortable by properties, fatty acids, cost, popularity, etc
- Unique page for every recipe(save as many as you want)

Planned features:
- Clean print view
- Find any recipe you have made on your user page
- Search recipes by properties, oils, etc.
- Recipe Cost Estimate
- Custom Ingredient Tables(Hide what you don't have or adjust properties, cost etc)
- Additives(EO, FO, Other)
- Embed recipe on forums or other websites

Tell me what else you would like in a soap calculator and I will see what I can do!

 

[Lotus]

Has anyone ever used this Lye Calculator? If so, please tell me what you think/thought.

http://www.soapguild.org/soapmakers/resources/lye-calc.php

 

[angie's]

I am cooking my soap and to my horror I notice oil has floated to the top, the whole thing looks quite liquidy/with small curdles. Is there anything that I can do to save this batch?

 

[Hazel]

How long have you been cooking it? Have you tried stirring it really well?

 

[Hazel]

Which one was hijacked? I checked all of the links in the entire thread and wasn't attacked. I did remove the two links in the first post since those calculators are gone.

 

[Fabius]

All the remaining links seem to be working. Maybe the problem was on my end. Thanks for removing the dead links.

 

[Hazel]

Could have been a glitch. Thank you for pointing out the old links. I don't realize older posts need cleaned up or corrected unless someone mentions it. Although, sometimes I do stumble across something when I'm doing a search.