Dual Lye disasters

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penelopejane

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Hi,

I have made quite a few dual lye soaps now and not one has worked out properly. They all have a rind around the edge so they haven't gelled all the way through.

I used:
OO 1000g
NaOH 130g
KOH 7.5g
Water 306 g
0% SF
31% lye conc

Then I tried:
OO 1000g
NaOH 130g
KOH 7.5g
Water 255g
0% SF
35% Lye conc
This has previously made a perfect soap.

No fragrance, no additives. Everything at room temp.
I CPOP by preheating the oven to 100*F then turn it off, put the wrapped soap in and leave it for 12-18 hrs.

Still no luck. Can anyone tell me what am I doing wrong, please?
 
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I'm the only knuckle head I know of who will admit to using a nigh 50% concentration for my castile attempts. I have also warmed up my olive oil a bit. The end result was a castile with 0% superfat but later developed a nasty bout of DOS either from FO or the type of oil I used.

I did let to soap cure for a while and I still did not like it. I also did not gel it but it did set up within 24 hours
 
... They all have a rind around the edge ...

I can't see anything unusual about your recipe (in either version) (30-33% lye concentration, 5-6% SF, 5% KOH at 100% purity).

If you were worried that something was astray with measuring, you could weigh the soap. There will be a little water loss from evaporation, but the weight shouldn't be too far from your initial (recipe) total weight.

So, if it's not an error in measuring, maybe it could be case hardening, like happens in dehydrated food. That would suggest that your oven temperature was higher at the start of the CPOP than the 100F you thought you had.
 
I can't see anything unusual about your recipe (in either version) (30-33% lye concentration, 5-6% SF, 5% KOH at 100% purity).

If you were worried that something was astray with measuring, you could weigh the soap. There will be a little water loss from evaporation, but the weight shouldn't be too far from your initial (recipe) total weight.

So, if it's not an error in measuring, maybe it could be case hardening, like happens in dehydrated food. That would suggest that your oven temperature was higher at the start of the CPOP than the 100F you thought you had.

The first one is 31% Lye conc and 0% SF
The second on is 35% Lye conc and 0% SF.

It wasn't the measuring it just didn't gel.
I've made the second one before and it was perfect! Driving me batty.
 
The first one is 31% Lye conc and 0% SF
The second on is 35% Lye conc and 0% SF.

It wasn't the measuring it just didn't gel.
I've made the second one before and it was perfect! Driving me batty.

This is why I don't soap on headache days - my math brain has walked off in protest :think:

I've only ever had rind when I used a too-hot oven. Sorry I couldn't help, hopefully someone will be able to offer a solution for you.
 
I don't think the purity of the lye would effect the rind, but are you sure your KOH was 100% pure? Anyway, as for rind, I've only had it a couple of times and it wasn't with 100% OO soaps and I don't really know why it happened in the first place. However, the rind effect slowly dissipated and is no longer visible in those soaps. I'm not sure how long it took, as one of the soaps is now 11 months old and I don't remember when I first noticed that the rind look was gone.
 
I'll take a photo tomorrow. It's not mold related as it was clean but has happened in two molds. It might be because it's cold here. I made ANOTHER batch and I put a pizza stone in the oven and heated it to 110*F wrapped and left it for 24 hrs and it came out ok - no rind. So it might be a temperature thing.

This time I mixed the KOH masterbatching and the NaOH masterbatching and added water then when they had heated up from their reaction I mixed in the oils and used the heat to get the soap up to temperature. Where as before I waited for it to cool again.

The KOH is 95% pure which is much better than most which are 90% pure.
 
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My KOH says it is 95% pure. However, I live in the humid south, and I KNOW it has absorbed some humidity, so I just use the 90% purity setting on the calculator, and it all comes out OK.
 
My KOH says it is 95% pure. However, I live in the humid south, and I KNOW it has absorbed some humidity, so I just use the 90% purity setting on the calculator, and it all comes out OK.

I will check what I do.
A dual lye soap seems to be soft for longer than a single lye soap. Do you find that?
I cut the last one 24 hours after making it. UsuLly it's about 18 hrs.
 
Nope, I cut my last one at 12 hours, which is actually super fast for me. I normally wait 18-24 hours. But I decided to get it out of the wooden mold (which I can do without denting the soap loaf), and it was so hard that I knew I could not wait 8+ hours until I got off of work. And indeed I could not have waited. It was already harder than I normally cut it. However, we were having some warm weather that day, so the increased heat could have contributed to that. I know y'all are in autumn, so maybe you are having cooler temperatures?
 
When I did my dual lye Castile soaps, I also used [40% Lye] concentration so for me they hardened up and I was able to cut much sooner than usual. I found that to be the case with multiple oil soaps that I also did as dual lye soaps, but they were also at [40% Lye] concentration. So I don't know what affect the 5% KOH would have had otherwise.

A couple of times I used dual lye with multiple oils and a lower [30% Lye] concentration, but I was also working with an oil I don't normally use (palm shortening), so have no idea if that or the KOH or the amount of liquid impacted a slower firming up time than I thought I'd get. The soaps seemed a bit soft to start, but they did firm up pretty fast as I recall.
 
I've made well over a dozen batches of bar soap with 5% KOH, and haven't had any surprises or problems. They pretty much behave like my all-NaOH recipes as far as behavior in the soap pot, time to trace, time to unmold and cut, appearance of the bar, etc. It's been a real non-event for me so far.
 
When I did my dual lye Castile soaps, I also used [40% Lye] concentration so for me they hardened up and I was able to cut much sooner than usual. I found that to be the case with multiple oil soaps that I also did as dual lye soaps, but they were also at [40% Lye] concentration. So I don't know what affect the 5% KOH would have had otherwise.

A couple of times I used dual lye with multiple oils and a lower [30% Lye] concentration, but I was also working with an oil I don't normally use (palm shortening), so have no idea if that or the KOH or the amount of liquid impacted a slower firming up time than I thought I'd get. The soaps seemed a bit soft to start, but they did firm up pretty fast as I recall.

I can't get them to gel at 40% lye conc.

I've made well over a dozen batches of bar soap with 5% KOH, and haven't had any surprises or problems. They pretty much behave like my all-NaOH recipes as far as behavior in the soap pot, time to trace, time to unmold and cut, appearance of the bar, etc. It's been a real non-event for me so far.

Yes, I was pretty sure it would be something I was doing that was the problem. :(
 
2 attempts at dual lye. Both were not successful. The first was 100% OO. 5% SF. Use Smell of Freedom from Nurture. It seized and I was able to dump batter into the mold. My second attempt: 95% OO, 5% Castor Oil (the reduce the slimy feel of 100% OO), 5%SF. 6% FO - Smell of Freedom. 2nd time was very sad. [emoji17]
 
IMG_0883.jpg
 
Smengot -- Well, but are your problems due to the KOH or due to other issues such as an accelerating FO? I'm leaning toward the FO, frankly. But more concrete recipe info might be more helpful.

PenelopeJane -- You probably won't get the soap to gel when using 40% lye concentration. The soap will warm up, certainly, but it won't gel. That's one of the reasons why people use higher lye concentrations -- to avoid gel.
 

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