Whats the hardness of your bar

Soapmaking Forum

Help Support Soapmaking Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Happysoap

Well-Known Member
Joined
Sep 6, 2013
Messages
194
Reaction score
61
What number does the soapcalc give you for your bars? I am just curious. My basic bars are 45. And I am happy with that. The bars last a looong time. I just made a test batch for my insanely sensitive skin that has the hardness number of 38.5. It is still curing so I can not test it but I am wondering if it is good enough. I didn't use olive oil. Whats your target number?
 
Most of mine seem to be around 38-39 and I'm happy with them. I have a few that are softer and a few that are harder but to make a gentle, non drying soap I've found I have to give up some hardness.
 
Thanks for your replies. I realise that some will consider my question to be very silly. I take issue with soft soap. Thats just me. It took me a while to settle for 45. Thanks, I feel better now and I can now stop examining it every few hours.
 
Bars that are physically hard ... and bars that last a long time ... are not necessarily the same.

If you use a lot of coconut or PKO to get that hardness as high as possible, you are actually making a shorter lived bar. Yes, it will certainly be hard, but the lauric and myristic acids in these fats make soaps that are fairly soluble in water. That higher water solubility is why CO and PKO soaps lather freely and why they clean well in hard, salty, or cold water.

If you use palm, tallow, or lard, you're increasing the stearic and palmitic acids instead. All other things being equal, you'll get a bar that is both long lived and physically hard. But there's a tradeoff -- a longer lived bar will have somewhat less lather and less cleansing in hard or cold water.

If you want an estimate of "long life", subtract the "cleansing" number in soapcalc from the "hardness" number.
 
I enjoy the feeling that I made the soap and I enjoy using it. It annoys me when it melts away after a few uses. All my soaps are tallow, palm and since recently lard based. So I have good quantities of palmitic and stearic acid in them. They last a long time and are gentle on my skin. I don't use coconut cuz my skin is super sensitive to it-just another item on a looong list of things that irritate my outer layer. PKO is way too expensive here. I wanted to try shampoos or dog shampoos and I am afraid that my regular soap might be too harsh for that purpose. More soft oils, more conditioning, less hardness. Since I never made a soap this "soft", I can not stop staring at it and checking it every three minutes.
 
It will be fine. My shampoo bars are 20 and are plenty firm enough but are quite soluble so I have to make sure they are on a wire soap rack so it can dry really well.
 
There are other issues besides the fatty acid content that affects the longevity of soap. Long enough cure time vs. a "hurry to market" cure, a reasonably low amount of water in the recipe vs. "full water", a moderate to low superfat vs. higher SF, the use of additives that make the soap softer or harder, the way the soap is used in the bath, whether the soap can dry well between uses, etc.
 
Yes indeed there are other issues. My soaps with hardness 17 last almost as long as the ones with hardness 79 - and neither is my longest lasting.

Huge differences in the cure time and water discounts of course.
 
There are other issues besides the fatty acid content that affects the longevity of soap. Long enough cure time vs. a "hurry to market" cure, a reasonably low amount of water in the recipe vs. "full water", a moderate to low superfat vs. higher SF, the use of additives that make the soap softer or harder, the way the soap is used in the bath, whether the soap can dry well between uses, etc.

Since you mention it, does a lower SF make for a longer-lasting bar?
 
Do softer soaps lather more quickly?

Are there reasons to specifically make a softer soap?

My three batches so far (yes, I've slowed down after my initial rush!) have had hardness values of 46, 44 and 37. What would be different about a soap with a hardness of say 29 (the low end of the "recommended" range on SoapCalc)?
 
Last edited:
Softer soaps happen when a lot of soft oils are used. For instance, the two I used today... A bastille with some of the OO replaced with soy. The other is a shampoo bar with no hard oils in it at all. Again, it had no chance of getting hard. It's more a result of the oils chosen, rather than a deliberate choice to go for softness.
 
I use to obsess over the hardness number on soapcalc, but now I don't care much and just focus on the fatty acid profiles. I like my palmitic and Stearic numbers to be in the 20s at least since I know that is what makes a bar hard.
 
"...does a lower SF make for a longer-lasting bar? ..."

A lower SF makes the bar somewhat (or a lot) harder than the same recipe made with higher SF, all other things being the same. Physically harder bar -> less soap rubbed off per use -> longer lasting

"...It's more a result of the oils chosen, rather than a deliberate choice to go for softness. ..."

Yep, that's true for me too. I want a low cleansing (low myristic and lauric) and more conditioning bar (higher oleic, linoleic, linolenic). You can't get that with a recipe that has a lot of coconut oil or PKO. The main fat in most of my recipes is lard (42%) but even if one used mostly tallow (58%) or palm (50%) as the main fat, that doesn't leave much room for adding conditioning oils and still keep the hardness in the 40s without adding a good % of CO or PKO.
 
Last edited:

Latest posts

Back
Top