How much borax in cold process soap?

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Borax is only slightly soluble in water. For the 62 grams of borax in Earlene's recipe, you'd need almost 2 liters (2000 g) of water at room temp to dissolve all of the borax. That's a 32-to-1 ratio of water-to-borax.

I think borax may function in this soap as an abrasive as well as a pH regulator and water conditioner.

In her recipe, Earlene calls for the borax to be mixed in a little bit of water (25 grams water). I'd do that just to get the borax powder all wetted and any lumps broken up. But, no, almost none of the borax will dissolve in that tiny bit of water.
 
I am no expert, but doesn't borax stay grainy and function a little like the pumice? Back in the old days, we had powdered soap in public places, you pushed up on this lever and it fell out in your hand..... and it was gritty. I am sure it contained some or a lot of Borax. Got your hands clean, too. I do put a half teaspoon in water when I make lotion and it dissolves and acts as an emulsifier. But it isn't much and the water gets heated to 170 degrees. Good luck with your experiment.
 
@earlene , @Misschief , @DeeAnna , does the borax truly completely dissolve in the water, that is like lye dissolves in water into a completely clear solution? I first used a 1 part borax to 2 parts water and it didn't dissolve. Then I did 1 part borax to 3 parts water and it didn't dissolve -- but ditched that because it left very little water for the lye. What I have is more like a sludge of wet borax at the bottom of my cup of water.

I'm soaping right now and may just leave out the borax at this point.
I dissolved it in boiling water, as per the recipe I used. It did dissolve completely.
 
Dug into this a little deeper tonight. The solubility of borax goes up a lot as the water temp increases. According to the info I found, you'd need about 120 grams of boiling water to dissolve 62 grams of borax. That's about 4 ounces or 1/2 cup of water.

This doesn't jive with the idea of dissolving 62 g borax in just 25 g of water (about an ounce) as per Earlene's instructions. That said, I haven't made the soap so I don't know this from personal knowledge, so I'll defer to the experience of those who have tried it and learned what works.
 
I am no expert, but doesn't borax stay grainy and function a little like the pumice? Back in the old days, we had powdered soap in public places, you pushed up on this lever and it fell out in your hand..... and it was gritty. I am sure it contained some or a lot of Borax. Got your hands clean, too. I do put a half teaspoon in water when I make lotion and it dissolves and acts as an emulsifier. But it isn't much and the water gets heated to 170 degrees. Good luck with your experiment.
You just gave me a tactile memory, @Adobehead ! I had no idea then that it was borax.
Thanks, @Misschief , but mine is still not dissolved, even at a full on rolling boil -- it's still a 'sludge.' This will really be an experiment....
 
Yes, it has always dissolved for me, but I always boil the water and add it to the Borax, stirring until it dissolves. I weigh the vessel before and after dissolution so I know how much water to deduct from the total liquid called for to make the lye solution.
 
Are you purchasing this Borax:

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I mean this brand?

I don't know if there are any differences in using other brands or not, but it has always dissolved for me. I have also use it in the laundry for decades and it has always dissolved.

Edited to add from the 20muleteam Borax website:
In the case of Borax, the compound is dissolved in hot water. As with most minerals and solids, Borax becomes less soluble the lower the temperature of the water. So, when the mixture with Borax and water is cooled, the water holds less of the Borax and it falls out of the solution.
 
What I have is more like a sludge of wet borax at the bottom of my cup of water.

[/QUOTE]
I decided to give this a recipe a try too....just finished ! (tweaked a bit because I didn't have KoH or lard)... but had exactly the same problem with the borax. I was adding more from the measured water, then decided to heat it a bit more...and a bit more in the microwave, till it was about boiling....then it dissolved ! But as it cooled it started to go a bit sludgy again, so I quickly added it to the lye water and it all dissolved as I was stirring. Had some sugar in there too. Strained the lye into the oils of course. (Also added powdered orange rind and a bit of annatto with the pumice at trace)
 
Are you purchasing this Borax:

View attachment 45935

I mean this brand?
Yep, the exact same thing. Let's blame user-error. Thanks for all your help on this, though, I appreciate it. As my sludge cooled, the borax did re-solidify again. So I did heat it up in the microwave right before I added to my oils/lye mix but again, it did not dissolve completely and I was afraid of it getting too hot. I'll test it in 3 weeks.
 
I will love to see your soap Malleebird. I do like the addition of the orange rind and annotto for color.
Hi earlene...firstly thanks for the recipe ! Am having trouble with phone/laptop photo connection ? Just messaged my son to please help....again !! So hopefully will get it up soon.

I was quite happy with the way it turned out, not quite as scrubby as I thought it would be, but won't know until I use it....but I would add more orange peel next time and probably up the pumice too. It was a 500g recipe and I added 2 Tbs orange, 1 1/2 Tbs pumice and a good pinch of annotto. Maybe my pumice is finer than what you buy commercially ? This is from a piece I picked up on a beach and ground myself.... assuming that all pumice is the same ? Used eo's 10g sweet orange & 5g patchouli.

The recipe itself... when I said I tweaked it...I actually tweaked it more than I owned up to. I didn't have "Crisco, new w/palm" ? ....or any palm oil....but I found a block of Frymasta that had been in the freezer for about 4 years (that I was going to throw out). Labelling just said blended oils so I phoned Goodman Fielder... they seemed a bit vague (probably don't even make it any more) but said all their blended oils were palm, canola & sunflower. I thought I'd heard once that Frymasta was palm oil so I put in sopa calc as palm (30%) So I'm pleasantly surprised that it turned out as well as it did...for home use :)
Will work on that photo now....

BTW does anyone know anything about Frymasta ? Sorry... new topic I guess.
 
I know nothing about Frymasta, but a little more about pumice.

When you have your teeth cleaned and the dental hygenist finishes up by polishing with a gritty substance, that's very fine pumice (dental grade) in a paste. Small Pumice rocks are what you see on the surface of the vessel in which bonsai plants live. There are many grades in between.

I used fine pumice for my brother's soap. It's really rough enough. Some might prefer the medium grade, but my brother the blacksmith gets good results with the fine pumice. But then again, perhaps if you didn't want to use Borax and only use pumice, then the medium grade might be preferable. I can't really say, other than that when he used Lava, which I think probably contains a courser pumice than I use, it didn't get the blacksmith stains off his hands until he had washed every day for 5 days. So I do believe it's the combination of the two ingredients (in the right proportions) that does the trick.
 
I believe when I formulated that recipe I had been testing out dual lye usage with a variety of recipes and that just happened to be one of them. You don't really need to do dual lye. As long as you run it through a lye calculator and choose NaOH only, you'll get the right amount of lye you need for your oils.

Dual lye can improve Castile soap, according to several sources and around that time several SMFers were experimenting with the effects it would have on other soap recipes.

Since I did not really test this recipe as an NaOH only recipe, I can't say I know if it makes a noticeable difference or not.

So, I'd say just adapt it to your own circumstances. It will still get mechanics hands and gardener hands, etc. nice and clean with a good scrubbing. Oh, and let me recommend the use of a fingernail brush as an adjunct to the really dirty hands. Getting under the fingernails is so much easier with the fingernail brush.

In fact, I've been recommending it to everyone in my family during this pandemic for obvious reasons. It's not something I see in any of the literature (may have missed it or skimmed too quickly) but at times like these it makes more sense to scrub like a surgeon than the usual short hand wash that folks might do when they don't think about the possible spread of contaminants.
 
My notes, which I think came from Earlene, say:
"Use 1.1 oz ppo. Good for a mechanics soap.
"Dissolve the Borax in hot water held out from the total water for the recipe, then addbthe Borax solution at emulsion (for swirling) or trace. Since it is a solution, it can actually be added before emulsion."
How much water does it take to dissolve 1.1 oz of water. I had a recipe for 1/6 cup borax to 1/4 cup boiling
water and it did not dissolve.
 
@Misschief I know this is an older post, but I'm curious. In the recipe you linked, the oil percentage and water to lye ratio are simple enough for me to calculate and same with the borax solution, but do you remember what the SF calculates to? Seems that much coconut would not be mild in any way, shape, or form. That's actually the only reason I didn't try it before @earlene's recipe, which I think dh is going to love after it is fully cured.
 
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My notes, which I think came from Earlene, say:
"Use 1.1 oz ppo. Good for a mechanics soap.
"Dissolve the Borax in hot water held out from the total water for the recipe, then addbthe Borax solution at emulsion (for swirling) or trace. Since it is a solution, it can actually be added before emulsion."
Has anyone else had trouble with it dissolving in that small amount of water? I added 2 Tbs borax to 1/4 copy boiling water but it didn’t dissolve..??
 
Has anyone else had trouble with it dissolving in that small amount of water? I added 2 Tbs borax to 1/4 copy boiling water but it didn’t dissolve..??
Worked fine for me, but I boiled more water than I would need, poured the exact amount I needed into another container, and then added the borax immediately. A long as the water amount is more than the borax amount, I haven't had an issue. Just to see, I'll go try it now with your amounts (1/4 c water and 2 tbsp borax) and see if it works for me.
 
20230406_144439.jpg

This is what it looked like when I first added the borax to my boiling water.

So I put it in the microwave for 3-4 30 second bursts and got the solution to a rolling boil....

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When I pulled my cup out of the microwave and gave it a quick stir, the borax dissolved.

However, if you allow this to cool at all, it separates back out and the water sortof absorbs the borax. Here's a pic of after I allowed it to cool down for 5 minutes....

20230406_151136.jpg
 
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