bath bombs

[PippiL]

what makes a bomb very hard.I made a bunch, some came out really hard and some came out very soft and brittle.
Any advise? Thank you

 

[donna75126]

I had read that if you make them with just baking soda and citric acid that they turn out really hard.. I tried it last night and this morning they were very hard. But the weather was really good also no humidity

donna

 

[Hazel]

Was it the same recipe? I add kaolin clay to my bombs and they always come out hard.

 

[PippiL]

I add 3 tbs to 2 c of BS and 1 c of CA,plus 2 TBS of shea butter and 1TBS soybean oil.To much oil?
But the recipe was the same.

 

[Hazel]

That doesn't seem like too much oil but this is just my opinion. It looks like your oil percentage is approximately 13% or a little less which isn't much more than I add. However, I'm guessing on the weight so your oil percentage might be a little higher. I always weigh ingredients so my recipes are in percentages. I checked the ones in which I've used oil and the oil percentages range from 6% up to 12% (I need more oil if I'm using a drier oil like jojoba or hazelnut as compared to a fattier oil like avocado). I know I have used cocoa butter in bombs but it appears I didn't write down how much I used in the recipe. Apologies! I don't always add clay. I checked my recipes and some have salt in place of the clay. The percentages are approximate because sometimes I use a little more of one ingredient or I decide to add a little less clay or salt. But the percentages are close to what I posted below.

50% baking soda
25% citric acid
25% salts (dendritic, sea or Epsom)

60% baking soda
30% citric acid
10% clay

donna75126 mentioned humidity which may be a factor. Did you do all the bombs on the same day?

eta: I wanted to mention I don't always use oil in bombs. Sometimes I just spritz them with rubbing alcohol to dampen the mix.

 

[lsg]

I use a reicpe that includes cocoa butter, the bath bombs come out nice and hard.

 

[donna75126]

I was using
8 oz baking soda
4 oz c.acid
4 oz corn starch
4 oz salt
I would measure out 1 oz of Almond Oil
And sometimes I would grate up cocoa butter

When I started added the oil I would just add alittle at a time and just keep on until I could form a lump and it would stay.

I had a harded time getting them to do right when I used corn starch. I still cannot make balls but I do pretty good with molds. I have been told that the added salt is really a waste of time because there is not enough in each bomb to be beneficial. The bombs I made with just baking soda and citric acid did really well but they fizzed int the tub super fast.

I used 2/3 cup baking soda
1/3 cup c. acid
and 1 tablespoon oil

 

[Hazel]

I never had luck with using cornstarch. The bombs wouldn't hold together. I've gotten good feedback on fizzing time for the bombs in which I add salt or clay. Maybe the salt isn't enough to be beneficial but it helps make them harder. Also, I pack bombs really tightly which also helps with lengthening how long they last in the tub.

 

[semplice]

I like how the cornstarch softens the water. My bf said the water felt "silky."

I tried adding lanthenol powder to make bubbles, but the bombs don't fizz they just kind of foam up and I got zero bubbles unless I held the things under running water.

I need to order some bigger molds (gonna get the mondo ones from BB).

 

[Rizack2]

I generally don't care for corn starch, it tends to leave a slight film in the tub and i'm to lazy to wipe it out every time. I like no mess in my tub. I also use a few spritz's of witch hazel to moisten the mixture and i think that make them hard as rocks. My recipe is 2 to 1 BS and CA

 

[lsg]

Including clay and cocoa butter will make a nice bath bomb.