Recipe Ingredient modification question

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Well-Known Member
May 4, 2008
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Hi all,

There are hundreds and hundreds of recipies on the internet but they don't match my mould size.

Is it possible to halve the base oil ingredients and re run the numbers through a calculator to work out the lye/water required?

Thanks in advance
You sure can resize to fit your mold. One easy calculator for doing that is ... -calc1.php

That one will resize and also has different units of measurements. I think Soapcalc will also let you resize, but it works on entering your percentages of oils instead of ounces.

If you didn't already see it, there is a sticky here that tells how to calculate the amount of oils for your size mold.

And welcome to the forum.
Hi, thanks for the link I will have a look at it.

I did read the sticky and have one question.

The sticky thread talks bout how to calculate the volume of the mould when you know how much soap batch you have.

The question I've got is

Mould = a
Oils = b
lye = c
water =d

so a = b + c + d

ie 12 oz = 6oz + 2 oz + 4oz

Does that make sense?
I had a hard time wraping my little brain around that sticky because the part where you multiply it by .4 was throwing me off...

Then I realized that we were comparing INCHES and OUNCES... so when we figure out the volume of the molds by doing the L*H*W caluclation, you're getting how many inches of volume the mold has. This has nothing to do with how many ounces it holds... then we do something *magical* and multiply it by .4 Doing this acccomplishes two things at once, it converts the inches into ounces, and it factors out the lye/water. So actually depending on how much water discount you take, you may have more or less wet batter in your mold because the end result of the formula (L*X*H)*.4 is only calculating how much OILS you'll need

SO... once you have gone through the exercise from the info in the sticky and know how many pound of oils your recipe should have, you can go to soapcalc and enter in your ingredients by weight or percent...I'm going to assume your recipe is telling you how much to enter by weight ie 8 ounces olive oil 6 ounces cocount oil, etc... if you enter by weight, just enter in the original recipe, then when all the oils are entered, click compute recipe. Now next to where it says "soap recipe" where you entered in all your oils, change your entry prefernce from weight to percent, then go to the upper center where it says total weight of oils and change that to the amount of oils you need.... you HAVE to change your entry preference from weight to percent so that the total oils weight field can be changed. Now click Compute recipe again, and voila, your recipe is converted!

Hope this helps.
I think Soapmaker Man uses this formula, correct me if I am wrong.
length x width x height x .4 = volume of mold
your sorta right, LxWxHx.4 = # of ounces of oils you need to fill the mold, not the actual volume of the mold. the volume the mold would will hold will be greater since you also need room for the lye solution.
At least that's how Paul explained it on the sticky. Also I belive pauls molds are by the amount of oils.. so a one pound mold holds one pound of oils... plus the lyesolution.

Paul you want to confirm this information?

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