Getting ready for my first batch

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kc1ble

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I'm getting anxious now, I got my recipe together, watched a ton of videos, perused these forums for hours, built a couple of loaf molds and finally ordered my supplies which are due to arrive Wednesday. Unfortunately, I have a busy weekend ahead with Easter so I will probably wait until the following weekend to begin. My recipe is as follows:

34.4% / 14.45 oz. Olive Oil pomace
29.82% / 12.52 oz Palm Oil
29.82% / 12.52 oz. Coconut Oil 76*
5.96% / 2.5 oz. Castor Oil

Superfat discount 5%

15.96 oz. Distilled water
6.01 oz. Lye (NaOH)

1 oz. Fragrance Oil (A little shy of the 1.31 oz. suggested by soapcalc, but I'll try it and see how it goes.

My recipe has been run through soapcalc and hopefully it looks ok, please chime in if something should be changed.

My molds are 12" x 2.5" x 3.5" ID and by my calculations, I need a 42 oz. weight of oil to fill my mold, hoping this is correct. They are wood molds that will probably be lined with plastic wrap on this batch.

Tell me what you think, hopefully I'm on the right track here.
 
I think you're going to have more soap than mold volume. Your mold might hold approx. 3.3 lb of soap batter and you're mixing up over 4 lb of batter.

Back of the envelope calc here - with the amount of water you're using (lye conc near 28% NaOH) I'd scale your recipe back to approx. 33 oz of oils for your mold. Perhaps someone else can verify.
 
I think you're going to have more soap than mold volume. Your mold might hold approx. 3.3 lb of soap batter and you're mixing up over 4 lb of batter.

Back of the envelope calc here - with the amount of water you're using (lye conc near 28% NaOH) I'd scale your recipe back to approx. 33 oz of oils for your mold. Perhaps someone else can verify.

I definitely understand what you are saying. The calculator I used calculates for oil volume which seemed very strange to me, I was wondering about the water volume, but didn't know if it was figured in the formula or not.

My formula was mold LxWxHx.40 = ounces of oil for recipe. Are there other formulas I have not found yet that account for water as well. Thanks for your feedback.
 
My formula was mold LxWxHx.40 = ounces of oil for recipe. Are there other formulas I have not found yet that account for water as well. Thanks for your feedback.

Your calculation looks right on the money to me, if you want to fill the mold to the brim.

It would be better perhaps to have a formula that is based on soap batter weight instead of oil, but in practice the one you used works pretty well.
 
Be careful of going with oil weight to know how much to fill your mold. I did this the first time and ended up with way too much batter because I didn't take the lye/water amount in to consideration. My molds hold 54 oz. So I design recipes for 34 oz of oil and then the water/lye adds the rest leaving some headspace so I can untold my soap easier.

Just remember you have lye water to contend with. Best of luck to you. Also one more warning I just did two batches with a superfat of 12% they didn't turn out, when I reduced the superfat to 5% the recipe worked perfectly. Be careful of your superfat amount it can cause a failure. Now I won't go above 8%

I do my soap with the CPOP method.

Robert
 
Im not in a condition to math, but anytime I use a new mold I have some standby molds handy, just in case.

Great idea, I will make sure I have a second mold lined and ready to go, just in case.
Your calculation looks right on the money to me, if you want to fill the mold to the brim.

It would be better perhaps to have a formula that is based on soap batter weight instead of oil, but in practice the one you used works pretty well.

I wonder if such a formula exists? I've only been able to find the one i used with a couple of minor variations.
 
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I wonder if such a formula exists? I've only been able to find the one i used with a couple of minor variations.

I haven't seen one yet, but I use the one you used and haven't had trouble with it. The ratio of lye (caustic + water) to oil will vary somewhat with the recipe, but it does take the typical ratio into account and I've never seen it off by as much as has been suggested. There is some kind of mistake involved there.
 
SoapCalc shows your total weight after water and lye. I usually try to go by that amount when picking my molds. It's been pretty reliable so far.
 
My molds are 12" x 2.5" x 3.5" ID and by my calculations, I need a 42 oz. weight of oil to fill my mold, hoping this is correct. They are wood molds that will probably be lined with plastic wrap on this batch.

My wooden loaf molds are similar in size to yours - 12 x 3 x 3.5 - and I do 32oz oil and have about 1/2" head room at the top. I feel that you will definitely have excess batter.

I have tried several times to calculate mold sizes using formulas... and always have excess batter. I've found the formulas to be unreliable.

Soapcalc does indeed tell you the total weight of your batter. I've found it to be fairly accurate.
 
My wooden loaf molds are similar in size to yours - 12 x 3 x 3.5 - and I do 32oz oil and have about 1/2" head room at the top. I feel that you will definitely have excess batter.

I have tried several times to calculate mold sizes using formulas... and always have excess batter. I've found the formulas to be unreliable.

Soapcalc does indeed tell you the total weight of your batter. I've found it to be fairly accurate.

With full water here, you're right that there should be some excess. We're not off by a mile though. A 1/2" head space in either of your molds could accommodate several ounces of oil.

The total weight of the batter in Soapcalc is fairly accurate if you weigh fairly accurately. It's the sum of the ingredients it's telling you to use.
 
SoapCalc shows your total weight after water and lye. I usually try to go by that amount when picking my molds. It's been pretty reliable so far.

I know the total weight of my batter as per soapcalc, but I can't find a formula to calculate the "weight" capacity of my mold. I will make sure I have an extra "mold" available and prepared before I make my soap.
 
If you haven't made your soap yet, I might suggest you weigh your empty mold, write the weight down, and then weigh it again after it's filled with soap. you could then subtract the numbers and know for certain next time you make a batch exactly how much your mold holds.
 
If you haven't made your soap yet, I might suggest you weigh your empty mold, write the weight down, and then weigh it again after it's filled with soap. you could then subtract the numbers and know for certain next time you make a batch exactly how much your mold holds.

Excellent tip, thanks.
 
Summerbeemeadow (AKA SBM) makes a recipe re-sizer, you just put your recipe in, then on the page you get when you "click here when done", there is a re-sizer.

http://www.summerbeemeadow.com/content/lye-calculator-and-recipe-resizer

Thank You, this is a wonderful tool. After running my recipe, I came out with an extra 1.51 ounces of batter. I will probably lose that much that will get stuck to my utensils and bowl. Now I feel comfortable not changing my recipe at all and we shall see how it comes out. (I will have a spare mold ready just in case)
 
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