Steep water discount questions

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McLasz

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Hi Again-
Can someone tell me what the difference is between water discounting and lye discounting? When people can cut their bars after 6 hours in a mold, is that a steep water discount? Does it take less time to cure this way? Are there advantages to doing this? If I wanted to use a 50/50 lye water solution, how would I adjust my recipe? Will soap calc do that for me?
 
This has been on my mind quite a bit - mostly because I recently became a huge fan of Ophelia's Soapery videos. She uses a 1.6:1 water to lye ratio and is able to cut in 6 hours and still has gorgeous swirls. Another soapmaking friend of mine also uses less water, she uses % which makes ZERO sense to me, so I'm not entirely sure how much water she is using. I'm having beers with her later this month and fully intend to ask her questions about it. It's on my to do list to play more with water ratios this winter while I am on a break from the soap biz.

Ok so... here's how I understand it in relation to your questions. Yes and no... No is that some soaps can be unmolded/cut quickly depending on what they are made of. For example, salt bars that are typically 70-100% coconut oil can be unmolded/cut within hours. However whenever I use sweet almond oil at 20% I can tack on 2-3 days waiting for it to be hard enough to unmold. [caveat: this may be how it plays with my recipe as a whole, your results may vary.] Yes is that being able to unmold/cut is because of water amount used.

It does not change how much time a soap needs to cure. Part of the curing process is evaporation, but the other part of it is molecular crystal formation. Depending on what oils you use will determine how the crystal formation and how fast that occurs. *This is a pretty basic over view of it in very generalized terms, forgive me for not being very sciency*

Advantages: you can make more soap!

With 50/50 lye solution, you are already using 1:1 water ratio. If you wanted to use, for example a 1.6:1 ratio as Ophelia's Soapery does, in soap calc you would change the Water setting to Water:Lye Ratio and enter 1.6.
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To use the 1:1 solution you would double the amount of lye in the calculated recipe - example 100g x 2 = 200g of 50/50 solution and add the remainder of liquid needed. 60g = (100*1.6)-100. In words: water to add = (water in solution * water ratio) - water in solution. Soap calc doesn't do the calculation for pre-mixed lye, but if you take a deep breath and put your mind to it, even math challenged walruses (walrusi?) such as myself can do it.
 
Water does not participate in the saponification reaction. It merely provides a vehicle to get the NaOH to the oil so they can react. Outside of using enough water so all of the NaOH is dissolved, there is no "correct" amount. Think in terms of "lye concentration". It can effect an number of things, including saponification rate. Most of us use 33%.

You need three molecules of alkali for each one molecule of oil that you want to saponify. If you have more lye than needed, the soap may burn you. This is never part of the plan, and should be avoided. We know exactly how many molecules of alkali there should be by weight, but the number of molecules of oil by weight will depend upon the type of oil, and will vary from batch to batch. To insure that there is no lye left over after saponification, we include a little more oil than necessary to allow for the variability of the oil. This is called Superfatting or Lye Discounting. The mode amount we use is 5%.
 
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Soapcalc uses *about* 2.2 : 1 water to lye as it's default. It's *about* because soapcalc uses water as a percentage of oils as the default. Using less water than that would be using a "water discount".
If you reset the calculations in soapcalc as amd pointed out you can set the ratio at 1 : 1 for water to lye. I typically use a 1.5 : 1 ratio.

Lye discount is simply not using 100% of the lye needed to turn *all* of the oil into soap. ( this assumes the SAP values for each oil are perfect and that the lye you are using is 100% pure).
I typically use 95 to 97% of the lye the recipe calls for by setting the "superfat" at 3 to 5%. While the two terms are NOT equal a lot of us non sciencey people use them to describe the process of not using all of the lye needed to react all of the oils.

Less water is water discount, less alkali is lye discount.
 
Thank you for your responses and help. I just about gave up last night as I made my third batch using a 50/50 solution and adding the correct amount of extra water using the math that amd confirmed for me (learned it on soaping 101) and measuring my ingredients to the drop, it turned out to be a brick- I couldn't do anything with it. SO DISCOURAGED!!!!! I refuse to give up though. Can someone weigh in on my problem? I thought that maybe my stick blender is too powerful for small batches? its over 800 watts- too powerful for small batches?

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Before you start to play with 50/50 lye solution, you should get your formula in order and be making soap that comes out right each time. That includes FO's and colorants
This will help you make sure that you are doing soaping right and then start to play with the % of Lye.

If you don't know how FO's and recipe should turn out, how will you know what went wrong.

I don't do 50/50, I like fresh made and can't have pre-made lye around in my house. So I can not comment on your writings
 
Here's my take on the "water discount" thing -- https://classicbells.com/soap/waterInSoap.html

A person is going to be better off to increase the lye concentration (or reduce the water:lye ratio, if you prefer that) more gradually -- more like 2% to 5% percent at a time. If you've been soaping at 28% lye concentration (2.6 water:lye ratio), try 30% lye concentration (2.3 water:lye ratio).

You really don't need to make huge changes to get distinctly different results. If you increase the lye concentration more gradually, you will have a better chance to develop your technique without as much chance of frustration.
 
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I agree with Lin and DeeAnna, you should know how this recipe and the FO/color behaves before trying the water discount. Your math looks good for calculating the lye solution and extra water. Have you used this FO before? When did you add the FO to the batter? How did you mix it in? How did you mix colors in - did you premix them in oil/glycerin/water, or add them dry? Did you whisk them in by hand or use the stick blender? All of these factors impact what happens when using a water discount.

A few takeaways I have gotten from watching Ophelia's Soapery and a few other soapers who use water discounts:
Stop stick blending when batter is at emulsion.
Pre-mix and hand whisk colors into batter. (O Soapery does occasionally stick blend, but this seems to correlate with FO's that deccelerate trace or using water to mix colors)
Add FO's at trace. [I add my FO's to my oils before adding lye, unless I am fragrancing different portions of the batter]
 
If you are new at soap making, get a simple, basic recipe and try it. I wouldn't try swirls or anything special until I got a good recipe down. For swirls, you need a slow moving reicpe and that comes with experience. My thought is that your FO is accelerating trace. I try to read the reviews of FO's before purchasing so I know if the FO will accelerate trace. Good luck with your soaping adventures.:dance:
 
This has been on my mind quite a bit - mostly because I recently became a huge fan of Ophelia's Soapery videos. She uses a 1.6:1 water to lye ratio and is able to cut in 6 hours and still has gorgeous swirls. Another soapmaking friend of mine also uses less water, she uses % which makes ZERO sense to me, so I'm not entirely sure how much water she is using. I'm having beers with her later this month and fully intend to ask her questions about it. It's on my to do list to play more with water ratios this winter while I am on a break from the soap biz.

Ok so... here's how I understand it in relation to your questions. Yes and no... No is that some soaps can be unmolded/cut quickly depending on what they are made of. For example, salt bars that are typically 70-100% coconut oil can be unmolded/cut within hours. However whenever I use sweet almond oil at 20% I can tack on 2-3 days waiting for it to be hard enough to unmold. [caveat: this may be how it plays with my recipe as a whole, your results may vary.] Yes is that being able to unmold/cut is because of water amount used.

It does not change how much time a soap needs to cure. Part of the curing process is evaporation, but the other part of it is molecular crystal formation. Depending on what oils you use will determine how the crystal formation and how fast that occurs. *This is a pretty basic over view of it in very generalized terms, forgive me for not being very sciency*

Advantages: you can make more soap!

With 50/50 lye solution, you are already using 1:1 water ratio. If you wanted to use, for example a 1.6:1 ratio as Ophelia's Soapery does, in soap calc you would change the Water setting to Water:Lye Ratio and enter 1.6.
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To use the 1:1 solution you would double the amount of lye in the calculated recipe - example 100g x 2 = 200g of 50/50 solution and add the remainder of liquid needed. 60g = (100*1.6)-100. In words: water to add = (water in solution * water ratio) - water in solution. Soap calc doesn't do the calculation for pre-mixed lye, but if you take a deep breath and put your mind to it, even math challenged walruses (walrusi?) such as myself can do it.
 
Another soapmaking friend of mine also uses less water, she uses % which makes ZERO sense to me, so I'm not entirely sure how much water she is using. I'm having beers with her later this month and fully intend to ask her questions about it.

Hi amd-
Wondering if you ever had beers with your friend and if she shed any light on the water issue? Just curious as I move forward and have even more questions!
 
@McLasz -- Have you read my article (see Post 7)? I go into some detail about this and give a table that connects lye concentration and water:lye ratio and gives suggestions for when you might want to choose a given lye concentration (or water:lye ratio) over another. You can use either lye concentration or water:lye ratio -- the numbers look different but mean the same thing. Use whichever one makes the most sense to you and ignore the other.

Honestly, making adjustments to the water content in a batch of soap is not a great mystery. I'm not sure why many soapers seem to think it's something unusual or even scary, but I concede I come at this hobby from a chemistry background, so I suppose I might have a different viewpoint than many people. Even so, it's really just a basic adjustment that isn't all that earth-shaking to do. :)
 
Hi amd-
Wondering if you ever had beers with your friend and if she shed any light on the water issue? Just curious as I move forward and have even more questions!

I did have beers with her, but we were sidetracked by... beer, lol. And FO's and FO Suppliers, and how much scent to use. I plan to play with lower water ratios this winter - I do soap at max water so I have lots of room to play, but my recipe is always ready to unmold at 12 hours and cut at 18-24, which I think is pretty reasonable. Other soapers have told me they are surprised that I can unmold that quickly with such a high water ratio. Anyways, sorry I don't have a clear answer for what my friend does.
 
When I use full water I too can still unmold at 12 hours and generally cut at 18 hours or so. I think because it gels quicker. I do mostly use a water discount to avoid glycerine rivers for the most part.
 

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