Hard, dry, and cracky-cut soap

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alexanderte

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I haven’t been active here lately as life have gotten in the way.

So I’m still having issues with some of my soaps/batches being hard, dry – and what I dislike the most – they crack while cutting. I still use a metal cutter. (Image attached. The one to the left in the middle does not have this issue. Approximately ¾ of my soaps look similar to this one, luckily.)

I’m not sure why this happens. I only make 100% olive oil soaps at the moment. I superfat at 5% and I have a 40% lye concentration. I blend until medium trace has been reached, although I’m not an expert at classifying different kind of traces. I mix olive oil at room temperature with lye water solution at 120 °F (49 °C).

The only thing that I’ve tried to adjust is how long to wait before cutting. The saponification time seems to vary a lot. For some batches it’s hard after 24 hours. Other times it’s soft, and I have to wait for 36 or 48 hours. But suddenly it’s hard and cracky. I guess I cannot “lock” this part of the process with a constant interval? I need to check by tapping my finger for every batch every 12th hour or so?

Do you have any advice for how to avoid the cracks? Am I cutting too late? Would it help to lower the lye concentration? If, so – how much? 33%?

cracked soap.jpg
 
I went back to look at some of my soap recipes and according to Soapmaker 3, most of them are from 26% to around 30% lye strength. I don't make Castile soap though, so maybe that would require a higher concentration.
 
Yup, at least that’s what I read in most posts about Castiles. 33% seems to be fine for most soaps, but Castiles are supposed to be made at 40%. I’m tempted to make a Castile at 33% and see how it turns out… :-?
 
I would try to cut a little sooner. The time may vary from batch to batch and I cannot explain why. In my experience, olive oil soap and tallow soap are the ones that have become unusually brittle for me.

If the soap is cracking when you cut it, try warming the soap in your oven at about 150 F (65 C) for 1/2 to 1 hour. Try cutting again while the soap is still warm. If it is still brittle, warm it another 1/2 hour and try again.

There is no reason why you cannot make a castile using 33% lye concentration. That works fine in my experience.
 
Then maybe my main challenge is finding the exact time to cut. It’s too bad that the saponification times varies, but maybe I need to get better at figuring out if the loaf needs more time. I have zero intuition for this, so I usually discover it when it’s too late – and the loaf is damaged from trying to unmold too early.
 
Then maybe my main challenge is finding the exact time to cut. It’s too bad that the saponification times varies, but maybe I need to get better at figuring out if the loaf needs more time. I have zero intuition for this, so I usually discover it when it’s too late – and the loaf is damaged from trying to unmold too early.

The advice given to you in July was to try soaping with lye a little cooler and maybe 33% lye concentration. This will give you soap that is a little more forgiving. It gives you a 24 hour or more window minimum before you have to worry about soap cracking or splitting.

If you've figured out trace now. I'd give that a try and see how you go.

I make a lot of Castile soap and each time I use same temps for lye solution, room temp EVOO, same trace and same method of CPOP and it is ready to cut at the same time each batch.
 
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I've found the best time to unmold and cut is very dependent on my water amount and/or whether or not my soaped went through the gel stage.

I mostly use a 33% lye concentration and encourage all my batches to gel, and I've found the earliest best time for me to unmold and cut is as soon as my soap has completely cooled back down from gel, which is somewhere around 12 hours so after pour, depending, although I normally find myself unmolding and cutting about 19 hours or so after pour because I'm usually busy with other things. In any case, I don't like going much beyond 24 hours before I cut because things get too hard.

It's been over a year since I've made 100% castile, but I usually use a 40% lye solution if my FO lets me, and I'm pretty sure it was ready to cut 12 hours after pour (after having gelled).

By the way, it's perfectly fine to make 100% Castile with a 33% lye concentration. The concentration to avoid with a 100% Castile is a 25% - 28% concentration (i.e., full water amount). Been there, done that, took forever to set up even though it fully gelled. lol

Knowing the best time to cut can get a bit tricky when one's soap doesn't go through gel, though. It could take anywhere from 24 to 48 hours or maybe even more, depending on the water amount.


IrishLass :)
 
This is super weird. This is what I might expect from a high coconut oil or high palm soap. Not a 100% olive oil! The fact that it acts this way and that it varies makes me think it's the oil. If you do things mostly the same way each time...it's gotta be the oil. Maybe try goggling that brand of oil and see if there have been any allegations of the oil being impure?
 
The advice given to you in July was to try soaping with lye a little cooler and maybe 33% lye concentration. This will give you soap that is a little more forgiving. It gives you a 24 hour or more window minimum before you have to worry about soap cracking or splitting.

If you've figured out trace now. I'd give that a try and see how you go.

I make a lot of Castile soap and each time I use same temps for lye solution, room temp EVOO, same trace and same method of CPOP and it is ready to cut at the same time each batch.
I did follow the advice on soaping with cooler lye. I wait for it to cool down to 120 °F (49 °C) for every batch. Should I go even lower? I guess it won’t be long before I do my first attempt at master batching the lye.

I really want to understand how to do things right at 40%, but once I get it then I might reduce the lye concentration. I just feel a lot more in control if I understand how to do it the hard way first.

So I tried to unmold after 24 hours for my latest batch. It didn’t work out. It was to soft to unmold and I damaged the loaf in the process. That was earlier today. I tried again now, after additional 6 hours, and it was perfect! The bars looks damaged from the previous attempt, but I noted down how the loaf felt after a total of 30 hours:

– Firm, but soft
– Can tap it with my finger without leaving mark in the loaf
– Rubbery feel with some friction when sliding a finger across

This might seem a bit too much to those of you who know this already, but this might be the solution to a problem I’ve had for quite some time, and I’m very excited. When sticking to 40%, I will check the loaf every six hour or so. I’ll note down the exact time it takes for every batch to reach this firmness.

Edit: What if the loaf is ready while I’m asleep or at work? :-|
 
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This is super weird. This is what I might expect from a high coconut oil or high palm soap. Not a 100% olive oil! The fact that it acts this way and that it varies makes me think it's the oil. If you do things mostly the same way each time...it's gotta be the oil. Maybe try goggling that brand of oil and see if there have been any allegations of the oil being impure?
I use a store brand olive oil. It’s not very expensive, but the quality should be okay. But maybe that’s what is causing it? I’ll do some research.

Edit: …but I’m pretty convinced that it’s the cutting-too-early-or-too-late (especially too late) that is causing the inconsistent results and crackiness.
 
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I just find that hard to believe because things tend to move slow with 100% OO soap. If this was a salt bar, then yes. But I've cut soap that's a week or more old and not had it do that.

Also, are you wetting your cutter? Wet the blade - it will slide through the soap, rather than the soap sticking too it and breaking.
 
I just find that hard to believe because things tend to move slow with 100% OO soap. If this was a salt bar, then yes. But I've cut soap that's a week or more old and not had it do that.
What do you find hard to believe? Not had to do what?

Also, are you wetting your cutter? Wet the blade - it will slide through the soap, rather than the soap sticking too it and breaking.
I’m wetting the cutter and also cleaning/wetting it between each cut. I also use a spatula to gently get the soap off the cutter if the soap sticks.
 
I have certainly had 100% olive oil soaps crack and chip when I let them sit to long before cutting. I use a 40% lye concentration with all castile soaps. I do keep an eye on it and as soon as it is firm enough I remove from the mold and cut. My molds are hdpe with removable side so I can remove a side and peek to see if it is firm enough in the middle. Even using the exact same olive I have had the cut time vary up to 24 hrs and mostly seems to depend on my trace. If pured at a light trace it can take up to 36 hrs to firm up enough to remove from the mold and cut, thick trace I can usually remove within 12-24 hrs.
 
Sorry, just realized my comment may have seemed rude. That was not my intention! I'm having a hard time believing that new 100% olive oil soap is behaving that way because it my experience that's the opposite of the way it behaves. When I have made olive oil soap - and it's been a while - it takes it several days to be firm enough to cut, and it doesn't quickly go from too soft to brittle. If you are using the same recipe, the same water, the same tools, the same techniques each time but you are getting such widely varied results - it's gotta be the ingredients.

When I said, "not had it do that" I mean I've left soap in my silicone mold for a week or more - I think 2 weeks once - and the soap did not crack like that when I cut it. But that's a lard recipe and I use a wire cutter.

I am wondering if the olive oil has some sort of chemical or preservative in it and that is making the soap do strange things?
 
Sorry, just realized my comment may have seemed rude. That was not my intention! I'm having a hard time believing that new 100% olive oil soap is behaving that way because it my experience that's the opposite of the way it behaves. When I have made olive oil soap - and it's been a while - it takes it several days to be firm enough to cut, and it doesn't quickly go from too soft to brittle. If you are using the same recipe, the same water, the same tools, the same techniques each time but you are getting such widely varied results - it's gotta be the ingredients.

When I said, "not had it do that" I mean I've left soap in my silicone mold for a week or more - I think 2 weeks once - and the soap did not crack like that when I cut it. But that's a lard recipe and I use a wire cutter.

I am wondering if the olive oil has some sort of chemical or preservative in it and that is making the soap do strange things?
No worries – didn’t interpret it as rude. I just needed some more context. :)

I see. To begin with I will see if cutting it at the right moment will make a difference, but if not then it might be the particular brand of OO that I’m using.

Do you use a 40% lye concentration? The biggest mystery to me regarding the soap making process seems to be the saponification process – and especially how long it takes. I need to do some more batches and see if I can get consistent results using my current process and recipe.
 
Lye concentration is something I'm a bit uncertain on. I use the "water as percent of oils". I have used anywhere from 40 to 33 and not had problems.

What super fat % are you using? Is it possible your soap is lye heavy?
 
The problem with using "water as % of oils" is that this setting wants to add more water to recipes with fats that have lower sap values and less water to recipes with fats that have higher sap values -- and this is exactly the opposite of what works best for most people. So if you use "water as % of oils" you have to over correct the setting to compensate for this contrary effect.

If you use water:lye ratio or lye concentration, this contrariness problem is eliminated and you get more consistency from recipe to recipe. These two settings mean exactly the same thing. People pick one and get used to it.

Dixie -- he said he superfats at 5%.
 
I think you may want to invest in individual molds when you can. It would cut the frustration out and at least you'd get even bars of soap, give or take. You also wouldn't have to deal with crumbly bars of soap. Other than that, you just have to find the right timing for when to cut your soaps. There's not much that could be done outside of using another soap recipe.
 

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