I bought some cruddy looking cast iron pans at a thift store recently. They cleaned up really nicely, but I'm having trouble with the seasoning part. I followed the instructions from Lodge and coated them lightly with vegetable shortening, placed them upside-down in a 350 oven for an hour, then let them cool completely. The shortening seems to have puddled, or pooled in the bottom and is not even distributed. Did I use too much, not enough, or will this even out over time? I have some other cast iron pieces that I've used for years, but I've never seasoned one from scratch. Any suggestions?