What are your best practices for preventing soda ash?

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SoapMakerDeluxe

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In my latest batch, I used a soap mold (minimal soda ash) and an improvised soap mold (a square cardboard box lined with freezer paper) which resulted in thin bars. The real soap mold bars are mostly good with minimal soda ash, but there's a lot on the thin bars. I looked it up and saw that having thin bars makes soda ash more likely.

But there is a little bit on even the good thick bars. Not as much but a little. Assuming they were covered properly, what are some good ways to prevent this?
 

KristaY

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The one thing that's made a big difference for me is using a water discount. When I used "full water" I got mad ash on most of my batches. I now use a water:lye ratio of 1.8:1 and I rarely get ash, or just a small amount. Certain FO's will cause more ash too and I have no idea why. Every time I use Nag Champa I get very thick ash no matter what I do with my water discount.

So if I do end up with ash I run the loaf under the faucet and rub it off with my fingers. If it's thick I rub it off with panty hose. But there are times it goes with my design so I leave it be. :)
 

Muskette

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I've done a lot of searching and reading about soda ash and how to prevent it, since most of my soaps have decorative tops and can't be covered or rinsed off. There really doesn't seem to be any definitive answer on the subject, but my interpretation of what I've read suggests that ash formation has a lot to do with the temperature of the soap and the evaporation rate of excess water in the first couple of days before saponification is finished.
Personally, the only way I've been able to prevent ash is to soap with a high lye concentration (~40%) and room temperature oils/lye. I'd love to find a better way though, since I prefer to gel my soaps. Also, many FOs accelerate at such a high lye concentration. I'll be keeping an eye on this thread!
 

shunt2011

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I agree with using a water discount and I've found that gelling and leaving it covered until it's cool makes a huge difference. I rarely get ash.
 

SoapMakerDeluxe

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The one thing that's made a big difference for me is using a water discount. When I used "full water" I got mad ash on most of my batches. I now use a water:lye ratio of 1.8:1 and I rarely get ash, or just a small amount.
Interesting, so maybe I could just plug this into the next batch for the soap calc.
Certain FO's will cause more ash too and I have no idea why
Sorry, what are FO's? I'm new (ish) here.
 
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SuzieOz

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I find I'm less likely to get soda ash the hotter I soap (which seems to be opposite of what Muskette experiences above ^) So If I soap hot and my soap goes through a full gel so that it has that waxy appearance when done it will have very little ash, if any.

So when I want a swirly design and soap at lower temperatures to keep the mix fluid, I'm more likely to get ash. Hmmmm ... also watching with interest.
 

IrishLass

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It's rare that I ever get ash, although it does happen from time to time. The times that I do get it, it is thankfully very light/thin and washes right off with a little bit of water.

In my earlier years of soaping (before I started using the method I shall spell out below), I used to get ash much more often. The worst cases of ash I ever got were when I tried to prevent gel, or when I unmolded and cut too soon.

My method: I mostly soap with a 33% lye concentration, my usual soaping temps are between 110F - 120F (sometimes a little higher, depending), I pour at med-thick trace into well-insulated wood molds complete with covers, I completely gel my soaps by placing in a pre-warmed 110F oven, which I then turn off as soon as my filled mold is placed inside, and I don't uncover my mold or unmold/cut until the soap has completely cooled to room temp. The only exceptions to that are my salt bars and my 100% CO soaps. I cut those when they are still hot or I'll never be able to cut them. lol


IrishLass :)
 

RobertBarnett

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I read in a book that you should spray the top of your soap with 91% alcohol and that that should eliminate the ash. I have never done it as I have yet to get ash.

Robert
 

Kamahido

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I read in a book that you should spray the top of your soap with 91% alcohol and that that should eliminate the ash. I have never done it as I have yet to get ash.

Robert
Are you sure about the percent of alcohol? I have tried that method several times and it INCREASED the amount of soda ash from negligible to noticeable.
 

TeresaT

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IrishLass, I'm with you on part of the process. I don't get ash when I soap fairly warm (as in summer time with no air conditioner), cover my mold and put it in a pre-heated oven. I prefer to soap at "room" temperature, so soaping in the summer is better for me than during cold weather. If I don't cover and force gel my soaps, I get a lot of ash. The last few batches I made were test batches and I let them gel in my small bathroom with the door closed while the heater was on. They didn't develop ash because that room is like a little sauna! But the few batches before that, where I didn't force gel and just left them (covered) on the shelf did develop ash. Admittedly, the plastic wrap wasn't exactly secure on any of them because I didn't want to mess up the tops.
 

shunt2011

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I too use less water, insulate and leave covered until I'm ready to unmold. I also give it a good spray of 91% alcohol and rarely get ash.
 

cmzaha

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Lately I seem to get ash on every batch so I just live with it. I have a lavender 40/42 that ashes so badly you can literally roll it off. I am starting to blame it on gelling, since I learned my problems with separation in my early days of soaping was from the high water I went back to gelling my soaps. Now I am in ash heaven. I soap 33-35% lye concentration at room temp so maybe you all can tell me why it is the opposite for me. I had no where near the ash problems when I put my soaps in the freezer to deter gel. Yep, figure that one out everyone...:) Never did I find alcohol to help one tiny bit
 

TwystedPryncess

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This is what I do when I don't forget to do it, although it sounds like experimentation is necessary. Climate and recipe could affect every batch.

My best prevention practices, and I live in a humid climate:

Spray with
 

TwystedPryncess

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Well then. Frodo wanted me to post. He head butted the new phone and I'm having trouble locating the edit button.

Spray with the 91% Isopropyl alcohol , regular Walmart kind. Cover with plastic cellophane. I poof up the cover if I have raised decorated tops.

I've found my ash continues to develop over the curing time, if it is going to happen, so if I am really concerned about, for example, a dark colored raised top, I keep mine covered after the cut. Just the same loose cellophane topper, although after the soap is hardened I can get a bit closer/tighter with it.

Afterwards, if it is still in curls or swirls etc, I use pantyhose or a small coarse paintbrush. It can be time consuming to remove ash in the little curly bits but I have compared my soaps before and after and it's worth it to me.

So there we go, rambling and didn't say a whole lot, but hope that helps.
 

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