How to figure how much oil for mold.

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ok, just to be clear

I wanted to do some sample batches or 1lb each and based on the calculations, it would take two of the cylindrical molds to hold one batch (I'm using plastic frozen juice containers to test the recipes). My question, though is that this is just the oil measurement, correct? So I would enter in the amount of oils into soapcalc and that would give me the total recipe (with water/lye) to make up the full batch?

So I enter, 1lb oil weight with the standard 38% water and use the end result. Right?
 
Yes, you calculate the volume of your mold(s) times 0.4, and that is the total oil weight you enter into soapcalc. I am not certain, but believe it is the 0.4 times the volume that takes into account that you will be adding water and lye. By magic or whatever, it seems to work. :D
 
Soapmaker Man said:
Hi everyone.I wanted to post this as a sticky so all could learn how much oils are needed for your mold. Here is the way to figure it.

Lets use a log mold that is 12 inches long, 3-1/2 inches wide, and you want to pour to a depth of 2-1/2 inches.

You take length X width X height of pour, that number X .40. So;

12 X
3.5=
42

42X
2.5=
105

105X
.40=
42 ounces of oils needed for this mold.

Apply these same numbers for your mold size, weather a log, slab, or block. :wink:

Paul

Is that TOTAL oils?? Including the EO's if you use any?? So then you would have to divide those 42 oz in to the different oils. Example: 20% coconut oil,, 10% Palm oil, 12 % Olive oil.
(Sorry I am new and trying to wrap my head around these calculations)
 
no worries!! that would be for total base oils in your recipe, additives are in addition to this number (so meaning any FOs or EOs are not included in that calculation and should be added extra in addition to it)



.... but yup, thats all youd have to do is divide the raw numbers into the total oils, converting them to percent and you can scale up or down your recipe to your specifications...

hope that helps!
 
I used this calculation for my molds and it came up a tad bit short of what I needed to fill the mold. It worked better when I calculated x.42, instead of .40.
 
Oils in mold (dimensions) - Bilal Hito

fill it up with water for an easy, approximate measure of how much oil youd need

- bilal hito bilalhito BILAL :)
 
I finally figured out a formula that works for me that is stone simple. I use grams instead of ounces when soaping so I can be more precise with measurements. 100 grams of oil = 1 inch of loaf mold length with a bar size of 2.5 x 3.5. So 12 inch mold = 1200 grams of oils. My lye to water ratio is generally 1:2. My bars weigh about 140 grams (5 oz) when freshly cut, give or take a little depending on whether or not I use any additives: milk, vegetable purees, honey, oats, clay, etc. Hope this helps somebody.
 
An easier mold size calculator

I found this works well, without having to calculate anything yourself:


[Edited by SMF Modmin Team to remove non-functioning link]
 
Thank you... Thank you

From a newbie who has been struggling with this - THANK YOU!!!

I havent made my first batch yet because I couldn't figure out how much to use, now I can get started..... wish me luck.
 
How to determin how much oil to use per mold

Summer Bee Meadow also has a calculator that will do this for you. It works very well, especially if you are using an odd shaped mold or a cardboard box. It will take the recipe you type in for the lye calculator and resize the oils for you.
 
I am completely ignorant when it comes to ounces and inches, so I did the math to figure out what it would be in cm and grams.

Take the volume in cubic cm (Length x Width x Height).
Divide that by 2,54^3 (which is 2,54 x 2,54 x 2,54) = 16,39 (to get the cubic cm into cubic inches).
And multiply by 28,35 to convert that into ounces.
Then multiply by the 0,4.

So it's:
(L x W x H) / 16,39 x 28,35 x 0,4

Which is the same as :
(L x W x H) x 0,692

That's for the metric users.


Please note: I have not tested this formula so use at your own risk! Althouth the link given by TopCat gives 0,657 for metric users... I don't know where it comes from but it is very close to what I found.


[Edited by SMF Modmin Team to remove non-functioning link]
 
Ifiyenia said:
Somehow, it doesn't work for me... I guess I'm the only one :(

Not sure how this works either. The rule of thumb I have always seen is L X W X D (or the volume) in inches multiplied by .4.

So I get the divide by 16.39 to convert cubic centimeters to cubic inches, but don't understand the convert to ounces at all. A one cubic inch volume of water converts to about 1/2 of one ounce (or .554 ounces more exactly) so I don't where the 28.35 comes from. One UK ounce converts to 28.41 cubic centimeters, but that's still not 28.35.
 
Just tried this calculation over the weekend - I had a new large mold and wasn't sure how much soap to make. Anyhow, it was kind of close, but did not make enough soap to fill my log mold to the desired height. I even added 4 oz of oils just for good measure (it's a 22 inch log mold). I think the difference is in the amount of water (or lye concentration) you use. I was using a fairly low water amount (33% lye concentration). I know people frequently use more water than that, so I'll have to take that into account next time. Is 38% pretty much the standard (I saw someone else on this post mention it)? I've used all different amounts, depending on the recipe. To the original poster - thanks for posting this. It was helpful to get a general idea of the amount.
 
Wooden soap molds are no longer the only option out there to use for soap making. In all honesty, you can pretty much use not anything as long as it does leak, and does not react with the soap and you can get the soap out of it later.
 
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