Having trouble with bath bombs

[Kiizka]

Last year I started making them and they came out great, tweaked here and there for what we have here.
I had a 6 month period when i wasnt making them and started again a month ago. So far all of my batches have something that seems to be an issue, they either crumble or crack. So if you kind people could help me can you look at my recipe and tell me if i should add something or leave something out.

2 cups of baking soda
1 cup of citric acid
1 cup of corn starch
2 tbs of oils
2 tbs of polysorbate 80
1 tbs fragrance oil
rubbing alcohol as needed

The humidity is around 40% in my home and its cold outside. Last 10 batches have either cracks in the middle or too dry and crumble. Im at my wits end and trying not to quit.

 

[lsg]

Here is a recipe that I have good results with. If you don't want to use sodium lauryl sulfoacetate, just make up the difference with citric acid and baking soda.

1 cup Citric Acid (7.4 ounces)
2 cups Sodium Bicarbonate (17.3 ounces)
¼ cup of Sodium Lauryl Sulfoacetate (1.6 ounces)
¼ cup Cream of Tartar (1.4 ounces)
½ cup melted Deodorized Cocoa Butter (3.2 ounces)
1 tsp essential or fragrance oil

Note: Ounce measurements given are by weight.

Make sure to wear a mask or tie a handkerchief over your nose when working with sodium lauryl sulfoacetate as it is very powdery and can irritate bronchial passages. Mix all of the dry ingredients until there are no lumps and all is well blended. Mix in the melted cocoa butter and the EO or FO. Mix until all is well blended.

 

[Cellador]

I get cracks when my mixture is too wet. Maybe try putting your alcohol in a spritzer, so you can add just a little at a time?

 

[Kiizka]

Here is a recipe that I have good results with. If you don't want to use sodium lauryl sulfoacetate, just make up the difference with citric acid and baking soda.

1 cup Citric Acid (7.4 ounces)
2 cups Sodium Bicarbonate (17.3 ounces)
¼ cup of Sodium Lauryl Sulfoacetate (1.6 ounces)
¼ cup Cream of Tartar (1.4 ounces)
½ cup melted Deodorized Cocoa Butter (3.2 ounces)
1 tsp essential or fragrance oil

Note: Ounce measurements given are by weight.

Make sure to wear a mask or tie a handkerchief over your nose when working with sodium lauryl sulfoacetate as it is very powdery and can irritate bronchial passages. Mix all of the dry ingredients until there are no lumps and all is well blended. Mix in the melted cocoa butter and the EO or FO. Mix until all is well blended.

Thanks for the reply! I might take you up on your recipe if things doesnt work out with mine anymore. I was hoping to test out adding kaolin clay and leaving out corn starch?Maybe that helps to stick together

 

[Complexions]

If you started out a year ago and they were great then stopped for a while and restarted and now they aren't so great, my guess is the problem is seasonal. Humidity in your area has changed and therefore your recipe might need to be tweaked a little bit. Crumbling can be from not packing and compressing the mixture hard enough or not enough moisture in the mix. Cracking can be from far too much moisture or far too little. Alcohol evaporates quickly, maybe in the low humidity switching to witch hazel will give you better results.