I made lotion bars using a "poor mans" double boiler that I've used in the past to successfully make lotion bars. I put my ingredients in a glass mason jar, put the mason jar in a pot of water and heat/boil the water. Everything was looking good and melted, but when I went to lift the mason jar out the bottom broke off and all the melted oils and butters went into my water. BUMMER!
I didn't have another mason jar, and I don't have a double broiler, so I just decided to use the pot to melt the oils directly. I'm not sure why I couldn't do that in the first place, because it seemed to work out....okay. I just put the lotion in freezer and I'll see if they turn out okay.
Also, this weekend, I must have shrink wrapped like.....a million soap bars. And I'm not even exaggerating. LOL.
Instead of using a mason jar for melting, try using a smaller pan in a larger pan, with the water in the larger pan. I don't have a "proper" double boiler either and that's what I do. OR I use a Pyrex measuring cup but put a paper towel or a dish cloth down in the pan with the water to absorb the vibration from the bubbles.