100 % Coconut oil soap rises

[MicheleH]

Hi, I recently made a first attempt at coconut oil soap for laundry - 100% CO, water, 1 % SF.
When I opened the lid of the mold the next day it had risen on top, kind of like a cake loaf would rise when being baked.
It was rock solid, so no vulcano.

I was making the soap testing a new mold (silicone loaf) but now I don't know if it was the recipe or the mold making it rise like that!
(ps I'm not new to soap making, just new to 100% CO soap and silicone loaf molds)

My question is: Is it normal for 100 % CO soap to become very hot?
Or do you think it was the mold being overinsulated? It has a thin wooden lid, and I put a towel over it as the room was chilly.

 

[KimW]

Sounds like you made a nice laundry soap. Yes, it's normal for 100% CO to get very hot. It's also normal for a wooden mold with a wooden lid to really keep in the heat. I wouldn't cover a 100% CO soap with anything but maybe plastic wrap because it does heat up. I've heard others here suggest elevating such a soap on cans to control the heat after pouring and while in the mold.
I don't know about the whole thing expanding and staying expanded all the way through though. I'm thinking you're seeing what one might call a heat expansion ridge (totally made up that term there, fyi), where the soap expanded from overheating and almost cracked, or cracked and then came back together.

 

[MicheleH]

Ok, thanks for that! Next week I'll make another soap and see if that recipe stays put!

 

[amd]

When I opened the lid of the mold the next day

For 100% CO soap, checking it the next day is too late, it will be too hard. You will want to cut it in approx 4 hours. Wear gloves. I think the last time I made laundry soap I cut at 6 hours and it still broke into shards. Once I cut as early as 2 hours - it was hot but fully set.

 

[KimW]

For 100% CO soap, checking it the next day is too late, it will be too hard. You will want to cut it in approx 4 hours. Wear gloves. I think the last time I made laundry soap I cut at 6 hours and it still broke into shards. Once I cut as early as 2 hours - it was hot but fully set.

Ah - yes! I totally missed that. Thanks, @amd

 

[MicheleH]

For 100% CO soap, checking it the next day is too late, it will be too hard. You will want to cut it in approx 4 hours. Wear gloves. I think the last time I made laundry soap I cut at 6 hours and it still broke into shards. Once I cut as early as 2 hours - it was hot but fully set.

Yes - I noticed! Luckily it was only laundry soap and was due to be grated anyway. It was crumbly on the outside but perfect for grating.