Hi There!
Okay, so I make about 200 bath bombs a week, crazy I know
But here is the recipe I use & they come out of my round ball mold quite nicely, the right consistancy is key with the fizzies, not to wet & not to dry...it does take some patience & testing until you know when it's exactly right.
1 1/2 cups citric acid
2 cups baking soda
1/4 cup cornstarch
1/4 - 1/2 cup dead sea salt (epson works too)
Mix together & then add the following:
Oils/butters (you can use whatever you like,but here is what I use)
1/8 cup shea butter
1/2 oz grapeseed oil
1/2 oz jojoba oil
1/2 oz castor oil
1/2 oz polysorbate 20 (you don't have to use this, I use it because it helps the oils to dissolve better in the tub)
1/2 - 1 oz fragrance oil (this is up to you depending on how strong your FO is)
Colorant if you desire
Mix it all together very well, breaking up the shea butter until you have little to no clumping.
Give it 5-6 light sprays of witch hazel or water, mix while you do this so the fizzing doesn't start. Okay now, is when your eye becomes handy. You should be able to take a handful of the mixture and squeeze it into a ball like light wet sand. If it crumbles quickly it's too dry, give it a few more squirts of water.
My only other tip to you is the molding process. I prefer the plastic sphere molds (like the Xmas ornament type), but your meatballer will work too. Don't pack the sides to hard, rather put enough mixture in them lightly & overfill the halves (kind of like you're shaping a clay ball). Then take both sides and mash them together, don't twist them together (it takes a little forearm power LOL). If this is done right you won't have to wait to unmold. Simply lightly twist the top off, and turn it over in your hand tap the other side & it should come out very easy for you. I have a video somewhere on my laptop if you'd like me to email it to you just let me know!
Good Luck, they're tons of fun!
Michelle