Bath Bomb Help - Crumbly/Powdery

[mirascreations]

Hi all! I've been reading through some of the threads and I can't seem to quite figure out what is wrong with my bath bombs. It took a little longer than usual for them to dry (left them for nearly 2 days to completely dry) and when they did, they seemed fine when I took them out of the molds. However, when I went to shrink wrap one of them, it started to crumble, but not apart, just to become deformed and not smooth on the outside. It seemed powdery but wasn't quite cracking and breaking apart. All it takes is a bit of handling for this to begin. So while they still work perfectly fine and aren't completely falling apart, the definitely do not look quite as good lol. I'll post my recipe as well:
- 3 cups baking soda
- 1 1/2 cups citric acid
- 2 tbsp kaolin clay
- ~1/2 tsp lake colorant powder (may have been a touch more than that)
- 2 tbsp sweet almond oil
- 1 tbsp polysorbate 80
- 1/2 tsp essential oil
and for this specific batch, i used maybe 1 or 2 spritzes of isopropyl alcohol.

If anyone could help me figure out this issue, that would be awesome, thanks! I didn't think it was too dry of a mixture when putting them together, and especially with the extended dry time, but it did rain which may have caused the slightly longer dry time on its own.

 

[shunt2011]

Firstly, weighing your ingredients will give you more consistency in your product. I measure everything in grams. I don't use oil in my bath bombs but use cocoa butter. Leaving them out too long will cause them to absorb moisture. I let mine dry over night then package. Sometimes, I'll warm my oven a bit then turn it off and put them in there before packaging. I just let them cool afterward. Just need to make sure they aren't too moist. Mine are so hard you can drop them and they won't break. Also, looks like too much PS 80. I only add about 1 tsp (guessing as weigh it). and I weigh my EO/FO's in grams. Your's doesn't sound like they were wet enough to pack well enough to be hard if crumbling.

 

[mirascreations]

Firstly, weighing your ingredients will give you more consistency in your product. I measure everything in grams. I don't use oil in my bath bombs but use cocoa butter. Leaving them out too long will cause them to absorb moisture. I let mine dry over night then package. Sometimes, I'll warm my oven a bit then turn it off and put them in there before packaging. I just let them cool afterward. Just need to make sure they aren't too moist. Mine are so hard you can drop them and they won't break. Also, looks like too much PS 80. I only add about 1 tsp (guessing as weigh it). and I weigh my EO/FO's in grams. Your's doesn't sound like they were wet enough to pack well enough to be hard if crumbling.

Alright - so I'll start measuring in grams from here on out (luckily I have a handy kitchen scale). So when I left mine overnight, it rained in the early morning hours so I switched them to an air-tight container for another night. Would that maybe have been too long? Also what temp do you set the oven to? I'll have to try that method next time.
How many grams of EO/FO do you put in then as well? I only did about a half of teaspoon of the EO I was using, but I do also have FOs to use as well. Sorry for all the questions - very new to this!

 

[shunt2011]

Alright - so I'll start measuring in grams from here on out (luckily I have a handy kitchen scale). So when I left mine overnight, it rained in the early morning hours so I switched them to an air-tight container for another night. Would that maybe have been too long? Also what temp do you set the oven to? I'll have to try that method next time.
How many grams of EO/FO do you put in then as well? I only did about a half of teaspoon of the EO I was using, but I do also have FOs to use as well. Sorry for all the questions - very new to this!

I just set it to the lowest temperature for about 5 minutes then turn it off. I use 2-3% depending on the IFRA usage rate for the scent I'm using based on the weight of the batch.

 

[atiz]

I don't think that Poly80 is too much with that much oil, but I'm not a real expert in BB's.
For me, epsom salts can help a lot, and so does a little bit of cream of tartar.