4 lb. mold does NOT hold 4 lb. recipe

[anchorandoak]

So recently I've decided to upgrade and use an actual soap mold instead of the shoe box I have been using. My father is pretty handy so he actually built this exact mold: http://www.brambleberry.com/ELF-4lb-Woo ... P5240.aspx

In the description the dimensions are listed as follows:
"Mold dimensions (inner): 13-3/4" (l) x 3-3/8" (w) x 2-1/8" (h), holds about 4 pounds of soap."

My father followed these dimensions exactly and the finished mold is that size. However, here's the problem I have - I have a recipe I have been using for over a year now and I scaled it 4 lbs. Once I went to pour the soap into the mold I was surprised to find that the mold holds nowhere near 4 lbs. of soap. Instead It ended up holding close to half. I am terribly confused.

Here's the recipe I used:

16 oz. Coconut Oil
28.8 oz. Olive Oil
19.2 oz. Palm Oil
9.09 oz. Lye
16 oz. Water

I must be missing something here...please enlighten me!

 

[lsg]

By my calculations you have 4 lbs. of oils, added to that is the lye and water, making the total amount of the finished product a little over 5 .5 lbs.

 

[Hazel]

Once I went to pour the soap into the mold I was surprised to find that the mold holds nowhere near 4 lbs. of soap. Instead It ended up holding close to half.

I'm a little confused. Are you saying it only held about half of your entire batch or it held all of the batch with space for more?

I calculated the mold should hold approximately 40 oz of oil weight for its dimensions. Your recipe has 64 ounces of oil plus another 16 ounces of water plus lye. So, your batch weight is over 5 lbs.

eta: Whoops! That's what I get for being slow. I see lsg has already mentioned the weight difference.

 

[sudbubblez]

Exactly what the others say... you have a 4lb *oil weight* recipe wich is actually a 5.5lb batch of soap. Molds are measured for total soap not oil weight.

 

[anchorandoak]

Welp, you guys were right on the money! When I took my soap out of the mold I weighed it before I cut it and it came out to 3 lbs. 15 ounces. So the mold is 100% a 4 lb. mold. Now I just have to figure out how to scale the recipe down so that I'm only pouring 4 lbs. of oil, water and lye combined. Good thing I have a B.A. in History and am really good at math :wink:

 

[Genny]

I think BB's lye calculator calculates the entire batch (oil, lye, water). http://www.brambleberry.com/Pages/Lye-Calculator.aspx

 

[Bama]

YOu can use SummerBeemeadows soap calc as it will resize your recipe and you can print it out

 

[new12soap]

you can also multiply your mold volume by 0.4 to get the total of oils needed for the batch that will fill the mold

13.75(l) x 3.325(w) x 2.125(h) = 97.15 (total volume)

97.15(v) x 0.4 = 38.86 ounces of oil

HTH