SoapCalc and what about temperature of oils and lye while mixing?

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Feb 22, 2021
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Dear all,

I try to find myself in the soapCalc ( it's a bit of rocket science for beginners :oops:). I stick to the rules that are explained on the website however I couldn't find any information about at what temperature I should mix lye and oils.
I'm testing lots of recipes at this moment however not all of them work at the same temperature....
Please help me how to find out when should I mix lye and oils?
Honestly, it doesn't have to be precise. You want the oils to be completely melted - not cloudy looking but nice and clear. (when I pot my hand on the outside of my stainless steel pot, the pot feels comfortably warm to the touch)
The lye solution can be a comfortable room temperature or warmer, but not hot. When either are too cold, they can start to solidify and mistakenly look like soap is forming, but will actually be a "false trace".

If you're not comfortable with that generalization, I can give you specific temperatures, but I'll need to know what oils you're using because I'll then go by the melting points of your hard oils.
When first starting out, 110F is a fairly good temperature. Start with small batch, uncolored or single color, and see how the batter reacts.

My recipe is 60% Hard Oils and I typically soap at around 80F-85F…gives me plenty of time to do my Drop/Chopstick Swirl. If I’m doing a single-color soap, I’ll soap a bit warmer ad give the Stick Blender and extra whiz or two.

When you make up your Oils and Lye Solution is completely up to you. When I first started, made everything up at the time I was making soap and of course, had to wait for the Lye to cool down. I eventually started making my Lye Solution the night before, but you want to make sure you cover it. Then I started making large batches of my soap and then sub-dividing for various soaps. I once make seven soaps at one time and I said I would never do that again.

These days I Master Batch my Oils/Butter…640 oz in a 5-gallon bucket and make up a couple of ready-to-use Lye Solution. I could fit a 1000 oz of Oils/Butter, but I don’t have a dolly for my bucket. Anyhoo…when I’m ready to make soap, I have a worksheet with all my molds on it which tells me how much Oils/Butters, Lye Solution and FO I need. After using a commercial paint stirrer on the end of a drill, I tare my container and scoop out however much oil I need and pop it in the microwave. I then measure out my Lye Solution and FO, do the do-wah-ditty, clean out my container and on to the next batch. As along as you keeps your lids on tight (make sure you wipe off the mouth our your Lye Solution jug and rinse the cap…I’ve kept MB’d stuff for a good six months.
I use a metal stainless steel bowl directly on the stove and heat til completely melted. I keep it warm enough to remain liquid, but cool enough to touch. I also use a stainless steel bowl for lye/water. I leave that in the sink til the bottom of the bowl is completely cool to the touch. So long as the oils and fats are melted still, it is good to go. I never ever measure exact temperatures.
Thank you all for tips.
When I started making soap I was very strict with temperatures because all the recipes are saying to mix lye and oils at the same temp. After making some batches I've realised that it wasn't efficient enough for me because I had to wait long time to cool down lye and warm up oils etc.

I will definitely try now to make it like you said and will see the results 😊
I am new but all over the board so far on temps. I do rely on heat transfer a bit. Just make soap with no design or scenting. I put the lye in the oils when it is dissolved and clearing up and usually pretty hot. The oils are usually on the cold side but I have melted first a couple of times. I personally have not seen too much difference.

It does seem most times that once the oils start interacting with the lye, everything will get a little warmer and I know it gets warmer in the mold cause you can feel it. Since I have never worried about temps, I haven't noticed much difference in end results and I am not consistent in everything I do before the end result.

I have did a lot of reading and seen where temp seems to be important but have not run into a situation where it has bit me yet not worrying about it.

I did when using aloe, use ice cubes during mixing lye but everything seems to get warm during the process when mixed with oils.

The one thing I have not did is have really high oil temps to begin with and that might change things. I have started with some oils being warmer then others but never hot oils and so have not seen what effect really hot might have.

I am new enough not to listen to but have no incentive I can see at this point to change my personal way of cold process.

I am watching this thread for the advice on temps and effects that others have had so I might be prepared when what I am missing in experience might be reveled so I can avoid future mistakes.
I would say that the majority of recommendations on temperatures are made so beginner soap makers can be safe and successful.

Soap making reminds me of's very individual, just as no two knitters knit the same, no two soap makers make soap the same. Take salt soap...I have tried three times to make it and it just doesn't turn out for me. I'm using 'tried and true' recipes, I'm following directions to the T, I let it cure for six months, but it never looks like the pictures. I think my 2-year old grandson could do better. LOL