Lye Heavy Soap

[McBaffie]

Hi all. Happy new year to everyone.
I recently made a batch of soap that was too brittle to cut properly. When I went back over my recipe I immediately spotted that I had mis-written the amount of lye required. So not only do I have a lye heavy soap; I know exactly how lye heavy it is.
My base recipe is usually:
Olive Oil 450gm
Coconut Oil 288gm
Shea Butter 162gm
Lye 125gm

However I have added 180gm of lye by mistake. :headbanging:
Now I can't work out how much of each oil I need to add in a rebatch. It's maybe simple maths, but I'm not sure how to go about it. Normally I put the oil amounts in the calculator and it gives me the lye amounts. Not sure how to work it out the other way around.
Can anybody help me with this?
Thanks in advance
McB

 

[earlene]

It looks like you use a 7% SF with this recipe, so I plugged it all into a lye calculator and come up with this. You need to double check it with your lye calculator to be sure.

For 1300 grams total oils at 7% SF using 180.5 g NaOH
OO Total: 650g (50%) - you need 200g more OO
CO Total: 416g (32%) - you need 128g more CO
Shea Butter: Total: 234g - you need 72g more Shea

How to figure it out: Change your option to percentages instead of grams, then change the total number of grams of oils until you get the 180g NaOH that you need to make up for. That gives you the total amount of oils for each of them. You then would add in the differences in what you already added versus what you needed.

This is easier with Soapee.com than it is with SoapCalc, because the soapee lye calculator makes the changes on the fly without having to look at a second page.

 

[McBaffie]

That's fantastic! Thanks so much for your quick response. Really appreciate it. I'll try rebatching this over the weekend.

Will the excess lye that is in the soap saponify the oils when I add them? Or will I need to do a crock pot rebatch?

 

[IrishLass]

It's actually very easy to do on SoapCalc.....

Someone may want to check my method and work for accuracy, but here are the extra amount of oils that I was able to figure out using SoapCalc:

Olive oil 198g
Coconut oil 126.7g
Shea 71g


This is how I figured it out: First, I found the difference between your lye amounts (55grams), and wrote it down.

Then I typed your original recipe amounts into SoapCalc and played with the superfat % until the lye amount matched 125g.

Once that was completed, I left everything alone as is, and only played around with the "weight of oils" box, lowering the total weight amount in the box to in order to lower the listed lye amount until it matched 55g.

Once it reached 55g, it was then just a simple matter of looking at the new gram weights of the individual oils amounts that SoapCalc had calculated and displayed out for me corresponding to the 55g lye weight (i.e., the amounts I wrote above^^^).

Edited to add- It looks like Earlene beat me to it.

Edited again to add- Uh oh, looks like the amounts I came up with and Earlene came up with differ a bit. Let me recheck my amounts.


IrishLass

 

[IrishLass]

I'm still getting the same amounts that I typed above. I re-typed in Mcbaffie's exact amounts of:

Olive Oil 450gm
Coconut Oil 288gm
Shea Butter 162gm

Then I messed with the superfat % until the lye amount came to 125gm ( a 7% superfat is what I got, the same as Earlene)
Then I kept everything the same (left all other input boxes alone) and messed around only with the weight of oils box. When I reduced it down to 396g is when the lye amount changed to match 55g (the difference in lye weight that McBaffie added).

But I'm not getting the same oil amounts as Earlene.


IrishLass

 

[earlene]

It's actually very easy to do on SoapCalc.....

Someone may want to check my method and work for accuracy, but here are the extra amount of oils that I was able to figure out using SoapCalc:

Olive oil 198g
Coconut oil 126.7g
Shea 71g


This is how I figured it out: First, I found the difference between your lye amounts (55grams), and wrote it down.

Then I typed your original recipe amounts into SoapCalc and played with the superfat % until the lye amount matched 125g.

Once that was completed, I left everything alone as is, and only played around with the "weight of oils" box, lowering the total weight amount in the box to in order to lower the listed lye amount until it matched 55g.

Once it reached 55g, it was then just a simple matter of looking at the new gram weights of the individual oils amounts that SoapCalc had calculated and displayed out for me corresponding to the 55g lye weight (i.e., the amounts I wrote above^^^).

Edited to add- It looks like Earlene beat me to it.

Edited again to add- Uh oh, looks like the amounts I came up with and Earlene came up with differ a bit. Let me recheck my amounts.


IrishLass

No, I made a subtraction error with the OO. That's why I say, double check in your lye calculator. Plus do the math.

Proof Reading my own stuff has always been my worst ability!

Will the excess lye that is in the soap saponify the oils when I add them? Or will I need to do a crock pot rebatch?

How soft is the soap right now? I'd do the crockpot method regardless. Until you do this, it's best to cover it as air tightly as you can because excess lye will react with the oxygen in the air to create another chemical that results in soda ash. That would potentially reduce the available lye, so the the sooner you do the re-batch the better.

 

[McBaffie]

Thanks so much. The bar was solid and very brittle. It's now ground down and in an airtight box. I'll rebatch it tomorrow morning, having quickly run it through the calculator again ;-)
Will let you know how it goes.

 

[earlene]

IrishLass, I have to say, your way is better. Fewer opportunities for math errors. While my way has 3 opportunities for math errors, yours would only have one. So I need to remember this one. Thanks.

 

[McBaffie]

Some feedback for you. The rebatch seems fine. Got it curing upstairs. The weather is very humid right now so it might take a while to cure properly. But I'm happy with the oil/lye ratios now. Thanks.
This is not the first rebatch I've done and I got that grainy texture with it again. I wonder what methods you might know of that help to eliminate, or minimise that. I watched a youtube video the other day where the lady whipped the rebatched soap in the crock pot with her stick blender. That seems a good idea. Have you any advice that could help make my rebatches a smoother texture in the future? I have read about soap makers doing rebatches on purpose to add delicate fragrances and embeds. How do they keep the soap smooth textured?

 

[DeeAnna]

I don't rebatch very often, but I've done enough to be of the opinion that more liquid in the rebatch results in a smoother texture, but there's more shrinkage overall. It's a tradeoff.

 

[earlene]

I agree with DeeAnna, as that's been my experience as well. You can get a smoother texture, but due to the shrinkage these soaps don't do as well if you want to use fine detail-type molds. Plain smooth cut soaps will shrink and may get a little misshapen, but you can plane them smooth again and they end up looking pretty nice, if somewhat rustic.

Is the graininess from one of your ingredients?

 

[McBaffie]

I don't think so. More likely just down to poor technique. As I say, this one came out better and I'm pretty confident that the next one will be better too. Just need a bit more practice at it. I'm thinking if I mill the soap to a powder rather than grate it it will be better too.