Slab bars are crumbly and bonus question about SL

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CpnDouchette

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I got a little tea tray (smaller than an A4 page size) and have used it twice. Each time my soap is very crumbly. Zap tested and its not lye heavy. It also is insanely ashy. I think I'm leaving it too long to unmould seeing as its a smaller batch. It also doesn't gel because of surface area and I dont CPOP because my oven is too hot on lowest temp. Am I right in thinking gelling might help, as would unfolding earlier?

Bonus question: I've had a search but couldn't find an answer.

Does SL add anything that regular salt doesn't? I've used both and *think* I prefer SL but I can't put my finger on why so its possible its all in my head to justify the price tag.
 

The Efficacious Gentleman

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When you say that you might be leaving it in the mould too long, are you just leaving it for a set time and unmoulding or are you checking it every 15-30 minutes and unmoulding it when it's ready?

If you change something (like a mould) then you might not be able to rely on how things were before. If you could unmould after X hours with one mould, it might not be close to that with a new one. So with a change in your process you have to keep checking back on it until you get to know how it works again
 

CpnDouchette

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Largely I soap in the evening and then unmold when I get home from work the following day, so no, I don't check it. I don't think I appreciated how much difference a different mould would make.
 

AliOop

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It can be difficult to get a small batch to fully emulsify without getting it too thick. Pouring with an unstable emulsion can be the cause of chalkiness, but it could also be too much SL.

The benefit of SL is that it doesn't negatively affect lather like salt does, and it can keep your batter more fluid. But I've had my struggles with SL creating chalkiness, too. I can only use about half the recommended amount, which perhaps is due to my recipe... not really sure. You could try reducing it and see what happens.

It does sounds to me like you are seeing some differences in gelling and non-gelling. If you have a heating pad, you can use that to gel the soaps in your small mold. This should help reduce the ash, and maybe the chalkiness because the soap will start gelling before the emulsion breaks. Simply cover the soap well and place it inside a box or insulating bag. You can put the heating pad on top or underneath the mold, then close up the bag or box. Turn it on medium to start, and leave it on until you can see your soap gelling. This could be in 30-90 minutes, depending on your recipe, your FO, and your heating pad.

Besides gelling, some other tips for reducing ash are to increase the lye concentration (less water), spray the soap with 91% RA after pouring, and cover the soap immediately after pouring. I've not had a lot of luck with RA, but the other tips work well for me. But I will say, I have some FOs that ash no matter what, as does any amount of activated charcoal. I've learned to embrace it.
 
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CpnDouchette

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I used about 900g of oil and about 50% lard so it wasn't a teeny tiny batch and I'm fairly confident it was stable when I poured. I did use a lot of AC. I think I may just give up with AC and use black mica because it never gets really black (presumably because I don't gel) and it always attracts soda ash. This was particularly bad though.

What's RA? I use isopropyl alcohol and, again, I'm not sure I notice a massive difference.

Kudos to embracing it. I don't mind on my loaves so much but my heart sank as I saw it creep across the most recent slab.
 

AliOop

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RA = rubbling alcohol. And my bad, I was thinking that A4 was a half-sheet of regular paper, but it's actually bigger than a regular sheet, not smaller. So no, that was not a small batch! Did you cover it right away after pouring, and leave it covered? Gelling would help, too.

It is sad to see a beautiful charcoal slab get ashy. Sometimes it does wash off pretty easily after the cure.
 

KiwiMoose

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The only time I had that problem was when I used a 'tray' type mold. It was very chalky with lots of ash.
I rarely use that mold now because it is difficult to get it to gel - gelling being the main thing for me that stops 'chalkiness'. Having said that, it was before my CPOPping days, so that is an option. The lowest setting my oven goes to is 60 celsius, is that the same as yours? If it's too hot you can still CPOP, but just wait until the oven has cooled off a bit before putting the soap in.
ETA - I only use cavity moulds if I add salt. For my soap loaves that I cut I use SL.
 

CpnDouchette

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Lowest it goes is gas 1 so 140 c, 275 f. I tried CPOP in the oven once not realising the magic 170 was in f and honestly couldn't tell whether it had gelled or not when I looked at it the following morning. I soap cool and my oven is useless (particularly on the middle shelf where I put it). I think I'm just nervous about volcanoes.
 
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