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DIY Homemade Shaving Soap

I would highly suggest not weighing in two liquid together - you run into all sorts of inaccuracies (density, reactions, etc.). I really think the method above will give you the most accurate results - you will know exactly how much is in there...
 
I'm tare-ing after the first oil is weighed. The only issue I can see is if I overshoot on the second oil in which case I'd need to start again and throw away some materials. Therefore, when I'm getting close to the correct weight I add the second oil drop-wise.
 
You are mixing liquids - therefore changing densities and therefore changing weight!
 
A change in density won't affect mass though, only volume. I'm measuring mass. I tare, measure a mass of 55 g of olive oil, tare, then add a further mass of 25 g of castor oil.

In any case, wouldn't that mean I'd need to saponify all oils separately then? Because as soon as I weigh them, I mix them in the cooking vessel. Let's say I weigh 74/55/25 g stearic/olive/castor. If mass did change through mixing, I'd have no way of knowing how much lye I'd need.

I should also add that this is another reason why I think a three oil soap is better than a four oil soap.
 
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Actually you are only after the mols (basically the number of molecules - their physical properties are at this point not important any more) - which soap calculator does for you.

I haven't done all that for a while now - but you mix liquids, you change density, buoyancy comes into play - trust me: it introduces an error. Else they wouldn't have gone out of their way to teach me, not to weigh liquids in liquids...

If you know how many mols are in there - that will of course not change, once you mix them. Only their physical properties will change. The mols will not even change after the chemical reaction, what you put in there has to come out.

Your (pure) weight measurement tells soap calc that you have x mols - because of the molar weight of the compound. Once you have that established - you (soap calc) only thinks in mols - the weight is not important any more.

Sorry I am such a bad conveyor of ideas - especially when it comes to physics, was never my strong suit :(

Another method would be of course to measure with syringe - but I fear a good glass syringe that is accurate enough will cost a couple hundred dollars and is a pain to keep clean. And before you ask: the change in density due to temperature of a pure compound in your case (temperature range of < 10C) is almost negligible...
 
bald as said:
I did mention "rabbit hole" !!
Click to expand...

Hey, if you can get a Nobel price - there must be a rabbit hole :D :D :D

OK, quick experiment to see if I am just a nutcase or a nutcase with too much OCD:

Weights only given as a thought, but the ratios should be similar. Your weighing vessel should be way lighter than anything you weigh in - I am thinking disposable plastic cups - cut in half for the first oil and cut almost to the bottom for the second oil.

Put first (large) vessel on scale, write down empty weight.

No need to tare and then put in first oil (bulk one) - I'd say 10 or 20g? Doesn't have to be accurate, just write down the exact number, so you know exactly how much is in there

Put second vessel on scale - again do not tare and write down the exact weight. Add second oil - I would suggest ~ 1/10 to 1/5 of the first one so ~1-4g. Again amount is not important, but exact number is.

Add the second oil to the first, without any utensils/loosing anything.

Weigh second vessel. Now you know, how much you have actually added to the first one.

Weigh first vessel - now you can compare the numbers and see if they are the same.

If I am too OCD - my sincere apologies :oops:
 
Gent's V2

I needed to make one last batch before I give back Steve's equipment.

1qd3XrY.png


This has a couple of advantages over previous batches of 48/36/16. 1) I used soapcalc.net instead of thesoapcalculator.com. The former rounds with greater accuracy than the latter. Accordingly, the amount of oils, water and lye is slightly different to that used in previous attempts. Differences are very minor though. 2) I accounted for the FA profile of the 'stearic acid' I have (basically 58% palmitic, 42% stearic).

Hydroxides were 50/50. Superfat was reinstated to 5%. Glycerine is 1/6 of total oil weight. Cook time was only 45 minutes. One puck was made with an actual batch weight of 170 g. Scent was 36 drops of cedarwood EO, 4 drops of tea tree EO.

The ingredients list on the label would look like: olive oil, water, palmitic acid, stearic acid, glycerin, castor oil, potassium hydroxide, sodium hydroxide, essential oils.
 
Gent's V3

Now with jojoba!

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I'm continuing my experiments with superfats. My experiences with lanolin thus far have left my believing that it is not the ideal ingredient for this purpose, at least in an olive oil soap. It is a fine ingredient of course and the post-shave feel it gives is outstanding but if all other things are kept equal, the lanolin containing soap is harder to lather than the vanilla soap. Even 0.75% w/w lanolin makes generating a lather more difficult. One certainly can get a fantastic lather but it's not as easy.

Enter jojoba. I was switched onto this ingredient by Chris Cullen of Catie's Bubbles who claims that when added in the right proportion it, "Changes the feel of the lather. It feels silkier, it feels smoother. It gives you a very different post-shave feel." I've never used Catie's Bubbles but I do know he is making a lot of soap which has a cult following so I figured I should give it a go. I've opted for 1% w/w of oils. (Incidentally, his French+ soaps don't contain sodium hydroxide. That's an experiment for another day.)

One other change was that I weighed the glycerine and jojoba simultaneously in the same vessel and I also added the essential oils (20 drops of vetiver and 20 drops of cedarwood) to this admixture. This had two advantages: 1) it allowed me to weigh how much EO I added (<2 g in total) and b) it allowed me to speed up the packaging as I could add four ingredients instantaneously.

Actual batch weight was 173 g.

The ingredients list on the label would be: olive oil, water, palmitic acid, stearic acid, glycerin, castor oil, potassium hydroxide, sodium hydroxide, essential oils, jojoba.
 
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khun_diddy said:
I'd love to do it without the palmitic but that'd bump up the cost per puck significantly as purer stearic acid is rather pricey.
Click to expand...

What's the price difference?
 
khun_diddy said:
'Stearic' is $6.50/kg.

95% pure stearic is $21/kg if I buy 20 kg of it.
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....do you think you could make that back (plus a little for your trouble) if you sold a puck or four to folks like me?
 
khun_diddy said:
'Stearic' is $6.50/kg.

95% pure stearic is $21/kg if I buy 20 kg of it.
Click to expand...
WOW - considering it's almost 50% of your soap ingredient - that would raise the soap price by ~150% !!!
 
Gent's V4

Two goals this evening:

a) To see what effect 100% KOH has on the soap;
b) To bump the scent potency up a little without it becoming overpowering.

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Workflow was significantly smoother working with only one hydroxide. The end result should be more accurate given there is one less crucial measurement that can go awry. KOH + olive/castor gave a more bubbly looking initial broth than KOH/NaOH + olive/castor does. When the stearic went in, it seemed more likely that the broth would go 'volcano' than with the mixed hydroxides. Slowly pouring the KOH avoided any eruptions though. Stirring during the cook, it was apparent that the soap was softer.

Cook time was 45 minutes. One puck was made with an actual batch weight of 183 g. Scent was 30 drops of cedarwood EO, 15 drops of vetiver EO, 5 drops of ylang ylang (first) EO, 5 drops of bergamot EO. Total EO weight was 2.41 g. Scent off the still warm puck is delicious. Essential oils were added simultaneously with the glycerin & jojoba. This works very well.

Tamping the soap down and packaging was far easier with the pure KOH soap. Although the puck is not completely set as yet, already it looks more professional. I can't wait to shave with it tomorrow!

Ingredients: olive oil, water, palmitic acid, stearic acid, glycerin, castor oil, potassium hydroxide, essential oils, jojoba oil.
 
If I don't see pictures of the lather it didn't happen :p
 
She was set when I woke up this morning. KOH soaps take much longer to harden.

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I test lathered then spent a few minutes looking for my camera. The ice cream peak is due to the jojoba. It has a pretty amazing effect on lather and I'll need to be careful not to add too much of it. In fact, 1.5 g in 120 g of oils would be just about the upper limit methinks.

The lather was very stable and smelt fantastic. I never know for sure until it goes on the skin though so I painted on and couldn't hold back my smile. Pure KOH is a winner, as is this scent combination (cedar/vetiver/ylang ylang/bergamot). None of the component notes dominate yet all play their part. Having now washed off the soap, there is a faint lingering aroma which is very nice indeed. I'll keep tinkering with the ratios of course and I would eventually like to add in a subliminal note on top, say, one drop of aniseed, or two drops of peppermint, or even a drop of juniper, but the basic idea is falling into place now.
 
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