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hmlove1218

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I've noticed that, except in more extreme cases, soda ash appears on top of a bar of soap.

However, I recently noticed something strange in a fresh cut soap. Right after I cut the loaf, I placed the end pieces on top of the other bars and later discovered that the bars beneath the ends DID NOT develop ash. But the end pieces DID develop ash on the sides facing upward.

Is it possible that ash forms mostly on top of bars because that's where the most water is evaporating from? And perhaps covering the tops helps lessen the evaporation from the top? Maybe the reason people don't have success with saran wrap is because the remove it too soon?
 
Yes here. If I discount a normal amount, cut, space close together, cover well with saran and cover with two towels, I have ash on the outsides and tops. My inner cuts are perfect. I have to leave it like this a week or so.

The cold weather and cold storage area made things worse.

Auntie Clara saw deep water discounts equals less to no ash.
Link in a second.
Edit, and here it is.http://auntieclaras.com/2014/08/intentional-crop-circles-water-discount-as-a-design-tool/_dsc3707/
I now do a 40% lye concentration and my ash is less than 1% total coverage. I have zero ash problems where I was starting to get it every dad-gum soap I made.

That equates Appx 1.5 water to 1 lye.
 
I just read a post of hers too where she did an experiment discounting water in same mold. One side 1:2.4 and other 1:1.4. The side with 1:1.4 had no glycerin rivers, the side that had 1:2.4 had them. Great pictorial along with description. Wish I knew how to link :-(
 
Some might disagree with me, but after few years of soaping I think I only found one major thing that causes ash for me and that is not gelling.
When I make single soaps they rarely gel and they are usually covered in ash. Soaps in log molds develop ash mainly on the end pieces where gel barely reaches and on the outer edges. Maybe that's what happened to your end pieces.
Sometimes I can maybe blame it on FO but I'm not sure yet. Ones with vanilla seem to make ash worse.
But that's my recipe and with my soaping conditions for someone else it might be different.
My fully gelled soaps almost never develop ash after cutting and cure.
 
I just read a post of hers too where she did an experiment discounting water in same mold. One side 1:2.4 and other 1:1.4. The side with 1:1.4 had no glycerin rivers, the side that had 1:2.4 had them. Great pictorial along with description. Wish I knew how to link :-(

Well this phenomenon is due to the use of titanium dioxide, and I think that it is also for the reason that TD was used in oils prior mixing the lye solution. I need to test it once more but I think that when adding TD @ trace the soap won't have glycerin rivers.
(I have also read that TD cuts down lather, is that true?)
Nikos
 
THe fact that gelled soap does not develop ash like ungelled is the same reason that the covered surfaces of ungelled soap can be ash-free. If you gel, saponification is happening in a far shorter period of time; if you zap test your bars after gel, they should be zap-free. Thus there is no unsaponified lye to react to air to make sodium carbonate (ash). If you keep ungelled soap completely covered until it is fully saponified, you shouldn't get ash, but you might be bald from pulling your hair out waiting forever to be able to unmold the soap.
 
Yes, keeping the soap covered for a period of time, depending on the environmental conditions (for me it's 2-3 days in winter), helps a lot.

However, about the direction in which the ash is formed, hmlove, I think you have a point... My sides never develop ash, the tops yes. As long as it is in the mold, this is normal. But the times I unmold and try to get rid of it soon, like the second day, it is formed again but only on the tops. It never crossed my mind to do your experiment though...

I too want to read DeeAnna's expertise...
 
I have only had ash on ungelled individual mold soaps. I cover and gel almost all my soaps. I'm sure there are many conditions that ash happens. I don't believe it's caused by TD as I use it in almost all my batches for years and don't get ash. At least not for me.
 
I get ash on any soap I make at one time or another. They dont always ash but then the next batch - bam ash. I tried to prevent it when I first started selling, tried water discounts, tried the CPOP, tried the plastic wrap. Sometimes I thought it worked, then a few batches later, bam ash.

Finally I thought why am I fighting this? I water bath most of my soaps before packaging anyway to get that glossy finished look. It removes all ash anyway.

Now I don't sweat it. Ash happens.
 
Sorry to post and disappear. I realize I didn't quite make my thoughts clear.

I don't bother with ash one bit. If it appears, who cares (not I lol). If it doesnt, that's great too.

The only time ash bothers me is if it dulls a pretty swirl on top, but I'm not really bothered enough to do anything about it.

All I was simply pondering is, since ash almost always appears on the tops, maybe it's because water evaporates upward the most. So maybe a pretty top could be spared simply by turning a fresh (but completely set up) loaf on it's side? Then, the side will have the most ash accumulation, and the beautiful top won't.

Edited for typos..dang you autocorrect..
 
I've found that lavender ashes like crazy. Once I forgot to spray alcohol on the top and the ash was at least 1/8" thick!
 

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