Bath bombs falling apart while drying

[VladDracule]

Hi all, looking for some help ASAP

 

My fiance tried making some bath bombs last night, and everything looked pretty good when removing them from the molds, however as they dried on the counter they started to develop cracks and a few fell apart. We added witch hazel to the mixture before molding, but arent really sure what else could be wrong.

 

heres pictures of when we removed them and what happenned after ~5-6 hours of drying on the counter

 

https://imgur.com/mYR4Jk5
https://imgur.com/oXSS1Jk
https://imgur.com/6gVVuom
https://imgur.com/qW7mLbM
https://imgur.com/cOnrNAY

[TallTayl]

Too much liquid will set them off like that. Use as little water/witch hazel/ alcohol as possible. 

 

I prefer 91% alcohol as it evaporates much faster, and still use a teeny tiny amount, just enough to moisten to stick.

 

also, ambient humidity plays a role. Humid and rainy days spell disaster for bath bombs. I ran a dehumidifier in my shop to keep the air <30% at all times for making and storing them. 

[TallTayl]

here's a short video of how I usually make them.

 

and the follow up after 2 hours.

https://youtu.be/hnxxa9cqzFg

 

[VladDracule]

21 minutes ago, TallTayl said:

Too much liquid will set them off like that. Use as little water/witch hazel/ alcohol as possible. 

 

I prefer 91% alcohol as it evaporates much faster, and still use a teeny tiny amount, just enough to moisten to stick.

 

also, ambient humidity plays a role. Humid and rainy days spell disaster for bath bombs. I ran a dehumidifier in my shop to keep the air <30% at all times for making and storing them. 

 

Does alcohol cause other problems? IDK it just seems like alcohol would and its nature could cause breakdown. Its really tough to figure out the balance I guess, We live in AZ so humidity isnt usually a huge issue. It was around 40% yesterday maybe but with refrigerated air that should suck a good portion of the humidity out. You dont think its an issue with the recipe and now enough oils to bind?

 

I did add a decent amount of witch hazel but if i dont add enough it seems like they fall apart when removing them from the mold

Edited August 6, 2021 by VladDracule

[TallTayl]

13 minutes ago, VladDracule said:

 

Does alcohol cause other problems? IDK it just seems like alcohol would and its nature could cause breakdown. Its really tough to figure out the balance I guess, We live in AZ so humidity isnt usually a huge issue. It was around 40% yesterday maybe but with refrigerated air that should suck a good portion of the humidity out. You dont think its an issue with the recipe and now enough oils to bind?

 

I did add a decent amount of witch hazel but if i dont add enough it seems like they fall apart when removing them from the mold

I posted videos above that include the recipe I used. 

 

Alcohol was more successful than witch hazel in my trials. Witch hazel seems to linger too long and sets off the reaction. Alcohol 91% evaporates very quickly, leaving little to set off the reaction if you spray lightly and work fast.