Soap Swelling in Mold

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darelias

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So I just made this batch of soap and I am using a new mold I haven't used before. I am gelling the soap and I went to quickly peek at it and noticed is is bulging ever so lightly in the middle. I've used this recipe before and the fragrance oil. The only thing new it a single mica, Saffron from Workshop Heritage and this new mold with lid, also from Workshop Hertigage. Any ideas what that bulge is?? I was soaping around 85-90 degrees when it went into mold.
 

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Looks like it's just heating up, or possibly overheating. Is the wood the new part? Wood can be a really good insulator that will allow/encourage a soap to heat up, even when soaping at a low temp...
 
Yes the wood is new. I previous used the harder silicone molds from brambleberry. I turned off the heating pad and unwrapped it. If it over heated too much what might happen to the soap? Would it crumble?
 
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Not sure how long you had it on a heating pad, but when soap overheats too much it can bubble up and out down the middle (what folks call "volcano"), or it can just form a crack down the middle on the top. Either way, the soap will still be fine to use, even if there might be a mess to cleanup.
I've had loaves that split down the middle that I was able to coax back together when I caught them in time - that is, while they were still soft - though you could still tell they'd split.
If it turns out crumbly, as far as I know, it won't be from the heat but will be from improper mixing or being lye heavy.
However, if by "crumble" you mean will it fall apart or somehow disintegrate in the mold, no. It might bubble up on you and spill out a little from the mold, but it won't fall apart. :)

I'd just put a towel under it and walk away...and then keep checking it every few seconds... Just kidding about the checking part. :)
 
I agree that it is overheating. You can elevate it on some blocks of wood, soup cans, or the like, and turn on a fan to blow on it. Circulating air around it and under it will help it to cool off.

Overheating doesn't usually affect the usability of the soap, but you can get heat tunnels, unsightly bulges, cracks, etc.
 
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The dark color in the center is a sign the soap has gotten warm enough to go into gel (soap's normal liquidy form).

The slight bulge in the same area means the gelled soap is getting hotter than you might want. If the temperature continues to rise, the soap will continue to bulge higher until it eventually cracks on top and/or forms open cavities inside.

Volcanoing, the situation where the soap batter saponifies way too fast and expands uncontrollably, normally happens right in the soap pot or shortly after the batter is poured into the mold. Your soap was long past that point.

There's nothing wrong with soap getting warm enough to go into gel. I prefer my soap to do that. But if the soap does decide to start expanding like yours, it's good to take AliOops advice to cool the soap. Ford's suggestion to adjust your insulation and or warming method is wise. And if it cracks, Kim's advice for repair works well.

It will be lovely soap.
 
Thank you everyone for the support, I put the covered mold on my concrete garage floor last night and left it all day. Stays around 50 or so degrees in there. Here is the cut. I love it! The original idea was to do a double hangar swirl and I did try, but the top layer was thick and I was afraid to be too aggressive and break the mica line. I am very very happy and I love my new mold!!!!!
tobaccobayleaf cut.jpg
 
Looks good! I recently made a confetti soap using orange and tealish blue - colors that are close(?) to the ones you used. I’m not wild about them in my soap, but now see the value of adding a neutral!
 
Looks good! I recently made a confetti soap using orange and tealish blue - colors that are close(?) to the ones you used. I’m not wild about them in my soap, but now see the value of adding a neutral!
I only used the orange because I got it in a sample, same with the blue. Normally I wouldn't think to soap with this color combo but adding a neutral really seems to pull it all together. It's funny because my original plan was for this to be black with intense orange and teal...I think I prefer it this way. I still need to work on my pigment amounts lol.
 

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