I asked a question (I think in last month's thread) about some butter that I made that didn't work out... I make it in the blender, and it seemed to separate, but not really completely -- the grains looked smaller than usual, and they didn't hold together. I have made butter successfully a couple of times since then, and I think I figured out the problem -- I overblended it. At first, I wasn't leaving the cream out at room temp to culture, and it took a while in the blender for the butter to separate. The time that didn't work, I had left the cream out and it smelled cultured. This time again I left the cream out for about 7 hours, and the butter separated really quickly. I turned on the blender for the first batch and went to scrub out a pot; when I checked on it, it had already separated and was on the way to being overblended. The buttermilk didn't separate really well and the butter was light and whipped in texture. On the second batch, I stood right there and it separated really quickly, and the butter was nice and firm and separated easily. So, I think that was the problem. It is nice that leaving it out and culturing it makes the butter making even easier. I also find that when I don't leave the cream out, the cream will "whip" in the blender and sit stiff up above the blades, so I have to keep stopping it, stirring it down, starting it up... etc. or shake the blender around to try and knock it down. That doesn't seem to happen with the cultured cream.