Lowest superfat?

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I do 3% SF in my regular soaps (thanks to cmzaha's advice regarding old plumbing). A few years ago I intentionally did a -20% SF in a soap made with bacon grease. I wasn't confident in my ability to clean the bacon grease thoroughly, and as this was completely experimental, I thought why not? I chose -20% from an older thread on the forum, although I don't remember the reasoning behind it. I left the soap alone on my cure rack and periodically zap tested it. It stopped zapping at around 5 months, so I let it sit for another month. My oldest son used the bars and said they were the best soap ever, they smelled like breakfast (I also used a good helping of molasses just to use up a bottle I had in the pantry).

All that to say, I would not be afraid of 0% or even a negative superfat. I've also used 0% in laundry soap and haven't had any zap test failures after the first two days.
 
I do 3% SF in my regular soaps (thanks to cmzaha's advice regarding old plumbing). A few years ago I intentionally did a -20% SF in a soap made with bacon grease. I wasn't confident in my ability to clean the bacon grease thoroughly, and as this was completely experimental, I thought why not? I chose -20% from an older thread on the forum, although I don't remember the reasoning behind it. I left the soap alone on my cure rack and periodically zap tested it. It stopped zapping at around 5 months, so I let it sit for another month. My oldest son used the bars and said they were the best soap ever, they smelled like breakfast (I also used a good helping of molasses just to use up a bottle I had in the pantry).

All that to say, I would not be afraid of 0% or even a negative superfat. I've also used 0% in laundry soap and haven't had any zap test failures after the first two days.
How very interesting! Thank you for your feedback, it sounds like a yummy smelling soap
 
I used 0% SF in all my single oil soaps that I made in my first year of soaping. Even then I got DOS in grapeseed oil soap and one or two others I don't recall which ATM. So even 0% SF doesn't necessarily prevent DOS, depending on the oils used and at what percentage. Of course, I was so new, there was likely some user error as well.

As mentioned previously by several, lye purity varies, but lye purity can be more accurately calculated as follows in these links and the formula adjusted as desired.

https://classicbells.com/soap/NaOH_KOH_Purity_Check.pdfhttps://classicbells.com/soap/lyePurity.aspsee also: Kevin Dunn's ScientificSoapmaking: the Chemisty of the Cold Process, chapter 16.2



For soap that will only be on display, I'd go with a negative SF setting, but not a large negative, because I got a lot of Ashy crystallization on the surface of soap with a high negative SF when I tried that experiment mentioned by a couple others in this thread. (See the thread on Andalusian superlye soap for a good read and what was going on as regards to why the experiment.)

So I'd suggest a smaller negative SF, say around -3%. AND as an added precaution, I'd not release the soap from my possession until it was zap-free.

FYI, I rarely make soap with more than 3% SF. As for the non-slime question for high oleic soaps, I don't notice it like others do, but I always thought that was related to my own personal skin feel as opposed to actual soap ropes that can be observed when soaping up with the actual soap, thusly:
1621084987722.png


Another image of interest if thinking about superlye soaps, is this one by @newbie :
1621085220012.png
(newbie's photo is from this thread.)

That might make for an interesting display soap, but could also alter the intended look of a fancy swirled
 
That is very curious about the ease of cleansing, but it does make sense. I read recently that a low superfat does not make a soap harsh either,
I'm currently using 0% SF in CP, always in LS and always in Transparent Soaps when I made them (Ancient History). The feel of 0% SF in both ZNSC and Trinity of Oils (See PDF attached) reminds me of the elegant feel of triple-milled French soaps. I wash my face AM & PM with ZNSC. I have dry, sensitive mature skin that delights in the feel of the creamy lather..

Having played around with various water discounts, I find that "full water" works best for me with a few notable exceptions, ZNSC for one. I can attest to the ease of clean-up. As a matter of fact, I can't remember ever doing an oily clean-up. That may be because I pay attention to temps (according to the oils/fats used) and I soap hotter than room temp, for the most part, especially for lard/tallow recipes.

I don't get soda ash or DOS and often wonder if I'm the only one on this forum so blessed? I am often perplexed by the regular mention of it. :smallshrug: 'Tis a mystery to me.

ETA: I would love to see a picture of your Soap art! So cool! :cool:
 

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I have soaped with 1-2% superfat for years even after someone in the forum, years ago, told me they would not touch my soap with a ten-foot pole, my answer was do not judge what you have not tried. That was during the days when everyone still thought you had to use at least 5% superfat. It is true I started using low superfat many years ago because of my old bad hillside plumbing, and also found I liked the soap much better.

As for the -20%, it was an experiment done which I think was called an Andalusian Soap, but I could be wrong on the name. Anyway, it was an OO soap with a very high water content using -20%, it only works with high water when using such a high minus superfat, which I know because I tried it using a more normal water amount and the soap never quit zapping. If I remember DeeAnna and I concluded that it took the extra water during the cure time to carry out the extra lye from the soap.
 
I used 0% SF in all my single oil soaps that I made in my first year of soaping. Even then I got DOS in grapeseed oil soap and one or two others I don't recall which ATM. So even 0% SF doesn't necessarily prevent DOS, depending on the oils used and at what percentage. Of course, I was so new, there was likely some user error as well.

As mentioned previously by several, lye purity varies, but lye purity can be more accurately calculated as follows in these links and the formula adjusted as desired.

https://classicbells.com/soap/NaOH_KOH_Purity_Check.pdfhttps://classicbells.com/soap/lyePurity.aspsee also: Kevin Dunn's ScientificSoapmaking: the Chemisty of the Cold Process, chapter 16.2



For soap that will only be on display, I'd go with a negative SF setting, but not a large negative, because I got a lot of Ashy crystallization on the surface of soap with a high negative SF when I tried that experiment mentioned by a couple others in this thread. (See the thread on Andalusian superlye soap for a good read and what was going on as regards to why the experiment.)

So I'd suggest a smaller negative SF, say around -3%. AND as an added precaution, I'd not release the soap from my possession until it was zap-free.

FYI, I rarely make soap with more than 3% SF. As for the non-slime question for high oleic soaps, I don't notice it like others do, but I always thought that was related to my own personal skin feel as opposed to actual soap ropes that can be observed when soaping up with the actual soap, thusly:
View attachment 57276


Another image of interest if thinking about superlye soaps, is this one by @newbie :
View attachment 57277
(newbie's photo is from this thread.)

That might make for an interesting display soap, but could also alter the intended look of a fancy swirled

This is so interesting and insightful, thank you so much for sharing, I am going to click on the links and read through them. The thought did occur to me of soda ash happening on top if the free lye is interacting with the air, so I am glad you also mentioned it.
 
I'm currently using 0% SF in CP, always in LS and always in Transparent Soaps when I made them (Ancient History). The feel of 0% SF in both ZNSC and Trinity of Oils (See PDF attached) reminds me of the elegant feel of triple-milled French soaps. I wash my face AM & PM with ZNSC. I have dry, sensitive mature skin that delights in the feel of the creamy lather..

Having played around with various water discounts, I find that "full water" works best for me with a few notable exceptions, ZNSC for one. I can attest to the ease of clean-up. As a matter of fact, I can't remember ever doing an oily clean-up. That may be because I pay attention to temps (according to the oils/fats used) and I soap hotter than room temp, for the most part, especially for lard/tallow recipes.

I don't get soda ash or DOS and often wonder if I'm the only one on this forum so blessed? I am often perplexed by the regular mention of it. :smallshrug: 'Tis a mystery to me.

ETA: I would love to see a picture of your Soap art! So cool! :cool:
I am intrigued by the feel similar to the triple milled French soaps! I may have to do a regular soap with 0% superfat after this project to test. My recipe has beef tallow, so I am curious about the warmer temperatures. I do lye water at room temperature, but warm up the oils to 100 F or 105. I definitely look forward to ease of clean up. Thank you for the PDF and info, I am going to go over it more slowly shortly.

Ps. I made this Frida soap for this client for a Mexican themed party, and upon seeing it, she suggested I attempt to make one for a regular person, and volunteered to be the first. So it should hopefully turn out similar minus the flowers.
9BD8F24B-A82A-4CC0-BD79-0695CEE629A6.jpeg
ou
 
I am intrigued by the feel similar to the triple milled French soaps! I may have to do a regular soap with 0% superfat after this project to test. My recipe has beef tallow, so I am curious about the warmer temperatures. I do lye water at room temperature, but warm up the oils to 100 F or 105. I definitely look forward to ease of clean up. Thank you for the PDF and info, I am going to go over it more slowly shortly.

Ps. I made this Frida soap for this client for a Mexican themed party, and upon seeing it, she suggested I attempt to make one for a regular person, and volunteered to be the first. So it should hopefully turn out similar minus the flowers.
View attachment 57282ou
I’m amazed at how beautiful that is!!!! One of my daughters loves Frida and makes tshirts with her picture . I would love that soap!!!!!!!
 
I’m amazed at how beautiful that is!!!! One of my daughters loves Frida and makes tshirts with her picture . I would love that soap!!!!!!!
I would love to see her t-shirts, I went on a Frida obsession while making it, read up all about her life and struggles and it was inspiring to learn about her. Thank you so much!
 
I am intrigued by the feel similar to the triple milled French soaps! I may have to do a regular soap with 0% superfat after this project to test. My recipe has beef tallow, so I am curious about the warmer temperatures. I do lye water at room temperature, but warm up the oils to 100 F or 105. I definitely look forward to ease of clean up. Thank you for the PDF and info, I am going to go over it more slowly shortly.

Ps. I made this Frida soap for this client for a Mexican themed party, and upon seeing it, she suggested I attempt to make one for a regular person, and volunteered to be the first. So it should hopefully turn out similar minus the flowers.
View attachment 57282ou
I’m so glad you showed us this! I could see it off to the side in your Forrest Gump Video and was curious. Lovely.
 
I’m so glad you showed us this! I could see it off to the side in your Forrest Gump Video and was curious. Lovely.
Thank you so much! I made Frida when we were doing last month lollipop challenge and one of my attempts at the skin color was too dark but ideal for the Nautilus shell color.
 
@cmzaha was the one that convinced me to use a lower superfat. We have old pipes and hard water so I felt I had nothing to lose. I mostly do HP with a few examples of CP thrown in now and again. So far, knock wood, the only case of DOS I have had was one bar given to my daughter that fell off the shelf where she keeps her soaps in her bathroom. Time wise, it had to be from my high superfat days but it also could have been from where she stored it, where it laid or any number of factors. But even from the first time I used a 2% superfat, the soap scum has been reduced and I don't have to clean out the drains in my bathroom as often.

@Zany_in_CO may have just convinced me to try 0% superfat in my next soap. I was going to soap yesterday but discovered that I didn't have that extra bottle of lye in my cupboard afterall. Now I have a few days to decide which recipe I really want to do. Something new, so I can use one of my recipes that I want to try out, or something old, so that I can compare the recipes of 0% and 2% superfat. Soaping is such fun!
 
As for the -20%, it was an experiment done which I think was called an Andalusian Soap, but I could be wrong on the name. Anyway, it was an OO soap with a very high water content using -20%, it only works with high water when using such a high minus superfat, which I know because I tried it using a more normal water amount and the soap never quit zapping. If I remember DeeAnna and I concluded that it took the extra water during the cure time to carry out the extra lye from the soap.
Yes! Thank you for the memory jog! That's right, I remember the water content being part of it as well. At the time I was soaping at 3:1 water:lye ratio which is why I felt comfortable with extreme negative SF. I no longer soap with that much water, but I also don't do as many experiments as I used to lol.
 

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