So I had a big soap making weekend. I decided to do my first master batch of oils since I was making around 10lbs of soap of various scents and additives. I measured all the oils out before adding to the main pot on double boiler, measured them again right before actually adding to the pot. Once all melted and the first lye solution mixed and cooling I measured out my first amount of oil needed. Once I got down to the very last batch, I was nearly 13 ounces short on oils so, based on my percentages I had to run a lye calculator again in order not to waste the oils but my last batch ended up very small. Is there a limit to how much time is recommended for oils being warmed? I didn't think they would evaporate so much (or at all).