Understanding and making a fulling soap

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mjcallsr

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I am hoping someone can clear some things up for me. To start with, I have never made soap and my knowledge was pretty much limited to what I found in the soap isle. After a week of browsing the internet, I now know a lot less. What I am trying to do is find a good baseline for a fulling soap. From what I understand, the main difference between a fulling soap and a hand soap is the alkali level. For a start, I have the following recipe:
50 lbs potash
5 gal (50 lbs) water
20 gal cotton-seed oil (per US Dept Agriculture, crude oil weighs 7.43 lbs)
20 lbs tallow
Add potash to water and let sit until cool. In separate container, mix cotton-seed oil and tallow then add potash/water.

So...
1. How does the ingredient ratio compare to what is normally used for hand soap?
2. To make a pure tallow soap, can I replace the 20 gal of cotton-seed oil with tallow (148.6 lbs) ?
and
3. Are the ratios literal - meaning if I only wanted to use 1 lb of tallow, do I decrease the others in direct proportion?
 

Susie

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Hey and welcome!

To begin with, I had no idea what fulling was. I found this, is this what you mean by fulling soap?

https://en.wikipedia.org/wiki/Fulling

If it is, then this is what I found on YouTube about wet felting:

[ame]https://www.youtube.com/watch?v=ubjc7YSmsLU[/ame]

In this tutorial, she simply uses grated bar soap into hot water to felt the wool. (see 3:20)

I checked a couple of other YouTube channels about wet felting, and they either use liquid castile soap, or the grated castile bar soap in water.
 
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TeresaT

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Hey and welcome!

To begin with, I had no idea what fulling was. I found this, is this what you mean by fulling soap?

https://en.wikipedia.org/wiki/Fulling
HA! I was reading the same article when you posted!

Welcome to the forum and thanks for the lesson fulling and fuller's soap. This looks like a question that DeeAnna, galaxyMLP and the other scientists need to answer.
 

DeeAnna

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Are you wanting this for finishing a woven fabric or for wet felting and fulling with loose fiber or for ??? And is this soap for small-scale or personal use or is it for commercial production and sale?

It looks like you're looking at recipes intended for larger scale production, but you haven't really defined the parameters for this project. It may make more sense to use other fats if making this just for personal or small scale use, so it would be more efficient to explain your problem a bit more, please.

My quick answer for use with wet felting is to use a low superfat soap made with olive oil or other high oleic fat. You want high alkalinity, but not necessarily excess alkali -- there's a difference.

ETA: And also you want low sudsing, another quality that a high oleic soap will provide.
 
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Susie

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I have the following recipe:
50 lbs potash
5 gal (50 lbs) water
20 gal cotton-seed oil (per US Dept Agriculture, crude oil weighs 7.43 lbs)
20 lbs tallow
Add potash to water and let sit until cool. In separate container, mix cotton-seed oil and tallow then add potash/water.

So...
1. How does the ingredient ratio compare to what is normally used for hand soap?
2. To make a pure tallow soap, can I replace the 20 gal of cotton-seed oil with tallow (148.6 lbs) ?
and
3. Are the ratios literal - meaning if I only wanted to use 1 lb of tallow, do I decrease the others in direct proportion?
I am going to answer questions in not the above order, but be patient with me, and we will get you some answers.

No, you can't convert literally without some extra steps. But we will use online calculators to help.

First, we need to convert all the oils to ounces in weights. Using this (http://www.aqua-calc.com/calculate/food-volume-to-weight) calculator, I arrived at the following:

Cottonseed oil = 126.42 oz by weight/gallon. 20 x 126.42 = 2528.4 oz
Tallow = 20lb x 16 = 320 oz

Next, we need to figure out how much alkaline (potash in this case) we need. You can do this one of two ways. One way is to go through this:

http://cavemanchemistry.com/oldcave/projects/potash/

Written by Kevin Dunn, and way above my mathematical ability.

The second is to understand that there is another alkaline that is readily available that we can plug into a lye calculator. Potassium hydroxide. We use KOH to make liquid soap all the time.

It seems to me, however, that if they can use liquid "castile" soap (that actually contains: Water, Organic Coconut Oil*, Potassium Hydroxide**, Organic Palm Kernel Oil*, Organic Olive Oil*, Lavandin Extract, Organic Hemp Oil, Organic Jojoba Oil, Lavender Extract, Citric Acid, Tocopherol) or Olive Oil bar soap that contains olive oil, NaOH, and water, then you can actually use any of the oils we commonly use for liquid soap. So, my question to you is are you willing to use other oils?

Edit: Cross posting with DeeAnna, who both soaps and felts. Ignore me, and pay attention to her!
 
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DeeAnna

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If you have never made soap and you don't know how to calculate a soap recipe properly, please follow Susie's advice! Don't use any recipe nor make any substitutions to a recipe until you know how to do the calculations (or know how to use a soap recipe calculator to do the math).

Always double check a recipe before you use it to make sure the lye weight is correct for the fats in the recipe. Published recipes may have errors or may not be formulated correctly, so never blindly trust someone else's numbers. Never make substitutions to a recipe -- different fats and/or different weights of fats -- unless you also recalculate the proper amount of lye needed for the revised recipe.

I hope you will better explain the problem you want to solve so we can offer reasonable advice. For example, if you believe the tallow-cottonseed recipe is a good choice for your project, then why are you asking about substituting tallow for the cottonseed to make an all-tallow soap? That's really going to change the type of soap produced, and this makes me wonder if you have a solid goal in mind or are floundering a bit. I'd sure like to know more about your goals and expectations rather than just make some guesses based on an old recipe.
 

mjcallsr

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Thanks for your reply. To clarify, what I'm attempting to do is to understand and maybe recreate fulling soap from pre 17th century with a tighter focus of pre-13th century Europe. For various reasons, I am focusing on a pure tallow soap made with potash. I guess my real question I'm trying understand is, regarding alkaline, how does the recipe above compare with tallow hand soap recipes I've come across (for instance 30oz tallow, 3.88oz lye, 11oz water) and, what would I need to change in the hand soap to match the alkaline level in the fulling soap recipe above. I've tried using some of the calcs online (SoapCalc, etc) with no success. I understand your concerns and agree with DeeAnna's post that going willy-nilly with this would not be a smart thing to do. As an aside, I have considered buying modern fulling soap for comparison but so far the smallest unit I can find is 500gal :( Addendum: some modern references note alkaline should be 11-12.
 
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mjcallsr

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No. two different processes. Generally felting is done with raw wool but you can abuse a knitted or woven article for similar results. Fulling is finishing woolens where, at the extreme, the weave or knit structure disappears. Think nice fulled wool dress or cape versus a cowboy hat.
 

DeeAnna

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I respectfully must explain that loose wool fiber is first felted (making the fibers adhere together) and then fulled (compressing and shrinking the felted fibers). A lot of folks don't know the difference and understandably think felting is felting is felting ... but it's truly not. :)

I have no idea how to translate the recipe you gave into a modern recipe for handcrafted soap because the soap making method used for such recipes is a boiled process where the soap was made "to a bite on the tongue." This method has no direct equivalent in handcrafted soaping. Any weight given for an alkali in an old recipe is only a guideline to get the soap maker started. He would know from experience how to finish the soap properly by adding more or less fat or alkali to get the correct type of soap.

As far as re-creating a pre-17th century soap, soaps of the day were not solid bars as we think of soap made from sodium hydroxide, nor were they pure potassium (liquid) soaps. It wasn't until the 1800s when purer alkalis were more widely used by large soap makers and this allowed them to make a hard soap. Before then, a soap maker would have used a mixed carbonate alkali (potassium carbonate + sodium carbonate) made from ashes. Depending on location, this carbonate alkali would contain more potassium carbonate than sodium (if you used inland hardwoods) or vice versa (if using seacoast plants such as barilla and seaweed). This carbonate alkali mixture could be used directly to make soap or it could be converted to a hydroxide alkali mixture by purifying the carbonate alkali and then reacting it with slaked lime.

Regardless of which alkali used, the alkali was mixed with fat and boiled together until a soapy paste formed that had a "bite to the tongue." (Basically this is what we call "zap" nowadays and means the soap was somewhat lye heavy.) The result was a soft brownish paste or jelly that was a mix of potassium and sodium soaps with various contaminants. This soft soap could be firmed up somewhat by adding some salt (NaCl) to convert some of the potassium soap to sodium soap, but I am not sure this would be a good idea for a textile soap vs. a soap meant for household or personal cleaning.

As far as the fats go, most soaps of the day would not normally have been made from edible fats -- they were more commonly made from less savory sources such as offal, bones, and kitchen waste fat. Exceptions would have been soaps used for medical purposes such as making pills or treating skin problems.

If you're willing to do an mid-late 18th century variant of this process, then you'd want to start with a mixture of KOH and NaOH. Boil the alkali with your fat until the fat is fully saponified and the soap zaps (bites) on the tongue. Reduce the water content by simmering until you get a paste like texture.

The handcrafted 21st century version of this soap would be to make a hot process soap using a mixture of KOH and NaOH. Calculate the amount of lye for the type and weight of your fats using the Summerbeemeadow calc that allows you to make a mixed lye recipe. Use a negative lye discount (meaning the recipe contains excess lye) so the soap is somewhat to moderately lye heavy -- perhaps -5% to -10%. I'd probably use a 25% lye concentration to make a soft paste that could be diluted further to a softer consistency.

ETA: Here's a quote from an 1842 soap making manual that describes making soap to a desired taste (zap), not to a recipe: "...The lie [lye] is added till the soap has acquired a good firmness, and when proved, a taste rather strong of lie remains on the tongue. As soon as this is found, then the soap must be let boil half an hour to ascertain whether the same taste yet remains; if not, a little more lie must be added, till the taste returns...."
 
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mjcallsr

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First, I would love to have some of your sources, not because I'm questioning you, but just to have them in my library. I have to admit, that I am leaning toward a 19th century interpretation. Early fulling was a dangerous occupation and I'd really prefer to avoid some of those complications. I've seen directions regarding tasting and for color of ring that forms but I feel I am lacking a point of reference for comparison. I thank you greatly for your input and will use your recommendations. As for Summberbeemeadow calc, the advanced version which allows adjustment to lye percentage is currently down. Would SoapCalc be a good alternative?
 

dixiedragon

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"I have no idea how to translate the recipe you gave into a modern recipe for handcrafted soap because the soap making method used for such recipes is a boiled process where the soap was made "to a bite on the tongue." "

Wouldn't this be what we call zap?

Perhaps contact some historical groups, especially in places like Wales with centuries-old wool production traditions?

This is so interesting and I hope you keep us updated.
 
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