A few questions before my first batch

[dixiedragon]

Yep, my go-to molds are all silicone because I hate lining! I only have one HDPE mold that came from Michaels or Hobby Lobby and I hate that thing with a passion. Everything sticks like the dickens and I never get it to release cleanly . . . even when I'm patient and wait for days. Now I only use it for test batches when I don't care how pretty it looks or how long it takes to extract.

I have a large HPDE mold. It's the divided mold on this page:
http://www.cumberlandacoustic.com/id9.html

I put 1 sheet of parchment paper (NOT wax paper!) on the bottom and grease the sides of the mold with mineral oil. Sometimes I grease the dividers, and sometimes I wrap a single sheet of parchment paper around each divider. Depends on my mood. I have found that a very large nail - about the side of a pencil - is great to thread through the holes in the divider to pull them out. The parchment paper is in a box of 1000 sheets from Costco.

That being said - If I had it to do over, I'd get a Soap Hutch. Those molds are totally HPDE (vs my mold that has a wooden base), and you can completely break them down so washing is easy. You can use the same mold for logs, divided bars, or a giant slab.

 

[Nettle]

So I have a few more questions...

If the plan is to fill a one pound mold, how do I calculate the oils? When I use SoapCalc it seems that I end up at 1.548 pounds of soap before CP cure... Also, how much water weight is typically lost during the cure? And another... If I want to use a butter in a CP soap, do I melt it first, and allow to cool to about 100 degrees before mixing in with the oils?

Thanks, you guys are great

 

[Obsidian]

For a 1 lb mold, use 1 lb of oil. I've never weighed my soap so I can't help with the amount lost during a cure. I melt all my hard oils and butters together then add my room temp liquid oils. I only heat my oils until they just melt, not sure what the temps are before I add the liquids.

 

[Susie]

My rule of thumb (which is born out by your calculations) is that you get 1.5 lbs of soap for 1 lb of oils. So, if your mold only holds 1 lb, I would use 2/3 lb (or roughly 10.66 oz) of oil in the recipe.

 

[Nettle]

So, a fair bit of Google research seems to say that an 8-week cure will reduce the weight of a bar by about 10%, though this will be less if a water discount is used. Fiddling with SoapCalc shows that a .75 pound oil weight will produce 1.161 pounds of soap, which after full cure will be just about a pound. Do these numbers look right?

And another question.. Regarding EOs and FOs.. Does a mixture of the two product soap with better scent longevity than EO alone? In Soap Calc there's a setting for Fragrance Ratio and Fragrance Weight.. What are these two really telling me?

 

[commoncenz]

So, a fair bit of Google research seems to say that an 8-week cure will reduce the weight of a bar by about 10%, though this will be less if a water discount is used. Fiddling with SoapCalc shows that a .75 pound oil weight will produce 1.161 pounds of soap, which after full cure will be just about a pound. Do these numbers look right?

And another question.. Regarding EOs and FOs.. Does a mixture of the two product soap with better scent longevity than EO alone? In Soap Calc there's a setting for Fragrance Ratio and Fragrance Weight.. What are these two really telling me?

1. The numbers look about right to me

2. I've mixed EOs and FOs in the past and mixing them doesn't seem to prolong the scent retention of either. If a scent is a fader, it will fade over time whether you mix them or not. Some folks swear that a little Kaolin (1 tsp ppo) helps with scent retention. I'll have a better idea about that in 6 months when I compare the two bars I saved from batches that I made 6 months ago that were identical in everything except the addition of Kaolin in one batch. So far, neither has seemed to fade much.

3. Taken from soapcalc regarding their Fragrance calculations:

The amount of fragrance to use is typically about 3-4% of the total weight of the oils used in your recipe. This is commonly specified as ounces per pound of oils or grams per kilogram of oils. Some suppliers will specify a usage rate for each of their oils.

Example: The supplier suggests a usage rate .6 oz/lb: 0.6/16 oz = .0375 = 3.75%. The metric equivalent would be .0375 x 1000 = 37.5 g/kg. Essential Oils are stronger and usually require a lower percentage than Fragrance Oils.

So, in essence, what you are doing is using a ratio of oz of fragrance/lb of total weight of oils (.6 oz/lb above). This will give you an amount in ounces (Fragrance Weight) to use in your recipe.

 

[Nettle]

Thanks for that, it starts to make some sense. Just for giggles, I went to Brambleberry and searched out Patchouli Essential Oil.. On the page I do not see recommended usage (unless I am missing something, very possible, the tryptophan is deep today) But I did find that they have a EO/FO calculator at

http://www.brambleberry.com/pages/Fragrance-Calculator.aspx

According to this, I should add .68 oz for medium scent per pound of Cold Process Soap.. To me, it's a little misleading, since it's not really per pound of soap, it's per pound of oil/butter... Right? Also, according to their calculator, I would use .72 ounces for Patchouli Fragrance Oil.. Not such a big difference in weight, certainly not as much as I could have expected.

Do you think the same rule applies for other additives, such as sodium lactate and oxides? And speaking of oxides, do the colors affect skin/clothing/hair? Will my blonde hair turn a crazy color if I add an oxide to a shampoo bar?

 

[Susie]

I would never, ever add color to a shampoo bar. You are just asking for trouble.