Using a homemade cylinder

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SPowers

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I was having trouble calculating the volume of a Pringle's can... I found a thread with the formula but the light wasn't going on! I ended up using the Soapmaking Recipe builder and only half filled the can. I just watched a video and realized I wasn't 'squaring' the radius and when I do the calculation now, I get an amount of oils that's almost double what Soapmaking RB gave me.
I'm wondering if anyone else has had this problem? Maybe I'm missing something on the recipe builder form??
Appreciate any input... thanks :oops: :oops:
 
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Zany_in_CO

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Appreciate any input
From my experience, a Pringles can holds 16 oz. soap, so use 12 oz. oils:
12 oz oils X a factor of 1.37 = 16.44 oz soap (approx)
BUT you don't want to fill the can to the top -- that makes it harder to remove the soap.
So use less oil or leave out enough soap to create 1/4" or so space from the top.
Be sure to lightly grease or line the can for easier removal. ;)
If that doesn't work, put the can of soap in the freezer for an hour.
Remove from freezer and wait 5 minutes then run warm water on it until it slides out.

HAPPY SOAPING!

PS: I'm math challenged 😁 so when I want to know how much soap my mold holds, I use this
Calculator & Recipe Resizer
First calculate your recipe. When you go to the results page, scroll down to the Recipe Resizer. That's where you can put in the dimensions of your mold to find out how much soap it holds. :thumbup:
 

SPowers

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I lined the mold so good on that score. It's interesting because 12 oz is 340 gr and soapmaker recipe builder says 360 gr of oils and that wasn't nearly enough. My can is not officially a pringle's can but a look-alike... wonder if it's bigger. I will try your calculator and see what it says.

edit: I can't figure out how to use that calculator... it's asking for a value for oils and I'm assuming it's % because I don't see an option to change it. That gives me a really low total.

edit #2: I figured out what I was doing wrong... I was using inches for mold dimensions rather than cm. These numbers make sense now and are almost double was soapmaker recipe builder shows.

I am either doing something very wrong with that or it is way off.
 
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Anstarx

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I've never used a pringle can as mold but I use PVC pipes. Same idea.
An easy way is simply pour water until it reaches about the height you want and weight the water. Soap is heavier than water so I usually time it by 1.1. E.X. if it can hold 1000g water it can probably hold 1100g soap. It's a crude estimation it worked well enough for me.
The complicated way is to calculate the volume of the can. Since water's density is 1g/cm3 than we can just use the volume calculated times 1.1 like before. I like to calculate it by hand but you can use a cylinder calculator like this: Circular Cylinder Calculator
It's more steps and you need to measure the can but you can get whatever height you want.
 

Zany_in_CO

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Courage, my friend. Don't let calculators intimidate you. We've all been there! :nodding:

You can do it. I could do it for you, but I would be cheating you of empowerment and the sense of satisfaction you get in overcoming obstacles. You might want to try calculating other molds that you already know the amount of soap they hold -- just to get used to using that calc.

BTW, I've been known to use the "fill with water" technique a few times. 😄 At the very least, it gives you a ball park reference.
 

SPowers

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It worked out in the end... more of a test batch from which I learned a lot. It's not often I let something intimidate me! Just makes me more determined to figure it out!
 
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