Calculating oil weight for new soap with large embeds.

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Well-Known Member
Jun 22, 2022
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Hi there lovely Soapers,

I have a question about larger embeds and volume of oil weight in a square mould.
Can anyone help me how to calculate the weight for the new oil?
I know this: to calculate your mould volume L x W x H x 0.4.
Do I take off the weight of the embeds of the total weight of new oils?
I’m not very good in English and I hope you understand what I’m trying to say..

Thank you for the replies.

Appreciate the help.

If you have the mould that the embeds were made from, fill it with water and measure the volume of that water.

Calculate the volume of your square mould (the L x W x H), then take away the measured volume of your embed.

What you are left with is the volume of batter you will need to use to fill your square mould.
(use this lower number in your oil calculation)
Thank you for kindly answering. It somehow answers it for me.
As I don’t really have a mould for the embeds as I cut them myself from a finished large batch I shall take away the weight of the embeds of a normal soap recipe of the particular mould. I believe that would be right?
I was worried about the fresh lye to add into ‘the filling’ soap but the embeds are a few days old and quite hardened up.

Thank you for answering.
You want to end up with only enough batch soap to cover the embeds without any overflow, right? In that case, what you need to do is look at the total batch weight (the amount to fill the mold.)

What I would do is to weigh the embeds and then deduct that amount from the Total Batch Weight that you would get if you were to make soap in that mold without the embeds.

In other words:

Create a soap recipe that will fill the mold and take note of the total batch weight, not the total oils weight.

Then, deduct the weight of the embeds (all of them that you intend to cover).

Then adjust your recipe to get the new reduced total batch weight.

The new TBW will cover the embeds without overflow.

How to do that can require a bit of back and forth play with your lye calculator, but it's not that difficult to do with calculators like soapmakingfriend and with soapee. I am not sure which calculator you use, but I suspect it will work for this method. I've done this a few times. It can be a bit fiddly, but it works.

Just remember to tamp down the filled mold to prevent air pockets around the embeds.
Thank you so very much! You have explained it very thoroughly and I did exactly as you said. I believe all worked out well.
I thank you🌺⭐🌺

Just need to cut the top embeds☺️


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This is the final result. Thank you for explaining. Really appreciate it. I have written it down as I’m really new into soaping. The only thing I don’t like about it is the not so dissolved speckles of cocoa oil.

Thank you for your help.
Have a good weekend. 🪬


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Good morning Earlene,

Thank you for saying that. Of course a few things are not right, like the white dots and the cutting( am so bad in that!)
It took me 2 soaps to make this actually. I like this way to work when you’re not satisfied with a soap at least I don’t have to waste any material. That’s the good thing about it. Are you in the UK or the US?
In the US they have a more free way with regulations isn’t it.

Have a lovely day.
Thank you for the feedback.
Yes, I am in the US, in the state of Illinois, which is more or less sort of in the middle. True, our regulations are much less strict than in the UK and the EU and in Canada. Personally, I believe the stricter rules are not bad at all, they are there to protect the consumer, and I find that to be a very positive thing indeed.

I really admire some of the EU's consumer protection laws, not just for cosmetics, but various other things as well.
Hi Earlene,

You’re not wrong there with protecting the consumer but I find here they go a bit into overdrive. It makes it very hard to work yourself around the do’s and dont’s and sometimes it can be a little bit confusing. I always have this idea that in the US you can make things that are impossible over here and the Americans are a bit more open and enthusiastic about new things which I love! I have a few uncles in New York and nieces and nephews in Phoenix Arizona and they are very open minded people, which I can find myself more comfortable with in then here in the UK. Its just a culture difference.

I hope you have a nice day and a good soaping week.

Thank you for the support here on the website. Its a really nice community here😊

Have a good one🪬