Calculating volume of odd shapes

[misskat22]

I know how to figure out the volume of a standard mold (loaf or slab) but I have some really cute little teddy bears and bundt cakes and have NO idea how to figure out the volume of them. Hubby said to fill them with water and weigh them..but I'm not sure that'll work for cp soap the same as it does for MP..or will it?

 

[Badger]

I believe you can fill them with water and that is the amount of oils you should use if I remember correctly.

 

[Nevada]

Measure and post the volumes of the mold in oz / volume.
I will do the math and post results for you!
Hey, it's what I do when on crutches and happy pills. :razz:
Roy

I know how to figure out the volume of a standard mold (loaf or slab) but I have some really cute little teddy bears and bundt cakes and have NO idea how to figure out the volume of them. Hubby said to fill them with water and weigh them..but I'm not sure that'll work for cp soap the same as it does for MP..or will it?

 

[lsg]

I agree with Badger, just fill them with water and then weigh the water. That will give you the total volume of the mold, including lye and liquid.

 

[misskat22]

Thanks lsg and Badger, I wasn't sure if that would work or not! I'll give it a shot

 

[new12soap]

I am curious to know whether you did this and whether it worked.

Fill your mold, make a note of the volume of water. Divide that number by 0.55, then multiply that number by 0.40 and that should give you the weight of oils to fill your mold. Each cubic inch holds 0.55 ounces of fluid (by volume) and holds 0.4 ounces by weight of oils in soap. This is a very rough calculation but it accounts for the difference between water and oil (oil is less dense which is why it floats) and the conversion from volume to weight.

Let's say I have a silicone bundt cake pan I want to use. I pour in water until it is full, and since I paid attention to how much water I started with, I know that this mold holds lets say 36 fluid ounces of water. 36 divided by 0.55 = 65.45 (that is how many cubic inches in the mold), then you multiply that by 0.40 = 26.18, which is how many ounces of oils you need to make enough soap to fill that mold.

HTH

 

[misskat22]

I haven't done it yet, what I'm probably going to end up doing is just saving some of a large batch to pour into these smaller molds. I know they're around 2oz so mixing up just enough soap for them (I have 7) wont really be worth it.

 

[christinak]

I did that with water and it was correct