# Measuring question

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#### Martin

##### Well-Known Member
I have a small size wooden mold I know how to measure for volume but what I am lost on is when I add every thing (oils, water, lye, what ever) that has to total the volume right? Because if I add the total for oils, when I add the water and lye I will be over right? I think I just answered my own question

Thanks,
Sonja

Sonja, take the length X the width, X the height you want to pour to, then multiply that number by .40. This is the amount of total oils only needed to fill your mold.

Paul

So I don't add the water and lye into total?

Thanks Paul

Sonja

Martin said:
So I don't add the water and lye into total?

Thanks Paul

Sonja

No, most molds are built for oils used only. I build all my TOG Molds that way. My TOG Mini 1 Pound Test Mold http://www.etsy.com/view_listing.php?li ... d=11100771 uses 1 pound of oils, but the log will produce 5, one inch bars that will weigh a full 4 ounces each after cure, or 20 ounces. The lye, liquids, fragrance or essential oils all add extra weight, but most of the water will eventually evaporate.

Paul

Hi I've done alot of reading on this and it just doesn't make sense to me.

Here is an example.

My mold volume is 0.09m x 0.06m x .5m = 0.0027m3

If you equate this to water weight, it would mean 2.7kg or 2700g

So does this mean that I need a total of 2700g of oil for my recipe? or does the 2700g include the water(200g) + Lye (100g) so the total oils are 2400g.

Hope this makes sense and I apologise for it being in metric.

crazyk said:
Hi I've done alot of reading on this and it just doesn't make sense to me.

Here is an example.

My mold volume is 0.09m x 0.06m x .5m = 0.0027m3

If you equate this to water weight, it would mean 2.7kg or 2700g

So does this mean that I need a total of 2700g of oil for my recipe? or does the 2700g include the water(200g) + Lye (100g) so the total oils are 2400g.

Hope this makes sense and I apologise for it being in metric.

You forgot to multiply by .4 The correct amount of oils only to be used is .00108m3 or 1.08 kg or 1080g of oils for your mold. For us US folks, the final number would be 38.16 ounces. :wink:

Paul :wink:

the batch i made over the weekend was 3.5 lbs. my molds are supposed to hold 4 lbs of soap each. that 3.5 lb batch filled up both molds. i'm glad i had both of them on the table ready for pouring.

go figure.

That formula calculates the volume for an average batch of soap. It assumes that the average soap recipe uses oils whose weight coefficient is 40% of the volume of the soap in cubic inches. If you use less dense oils or a larger volume of water for your recipe, then you will have more soap than the formula indicates.

If you have a base recipe that you use consistantly, you could tweek the formula for your own use by melting your weighed oils and recording their volume in fluid ounces. Mix your lye solution and record its volume in fluid oz as well. Add together for total volume in fluid ounces, then multiply by .554 to get volume in cubic inches. Then take the original weight in oz. of your oils and divide them by the volume in cubic inches. Use the resulting fraction instead of 0.4 in the mold formula.

Heh! 8)

The way I did it was to fill a mold up with water to the height I want soap bars. Then pour into large measuring bowl to see how much it is in volume. Volume and weight can be different but often not that much.

Antella,
if you are going to base your calculation on water volume/weight and you have a simple mould size, there is no need to fill it. Just use the calculation like I did above this was based on water which has an SG of 1.

Soapmaker man,
I was always under the assumption that the 0.4 should only be used if you are calculating in INCHES. Can you clarify please?

Thanks very much crazyk !

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