OK, guys, I'm desperate for some good ideas! Smelting out wheel weights, and my last 3 batches have turned to oatmeal. After the first batch, I emptied my pot, scraped out all the residue and started over with wheel weights that I tested individually with side cutters. When the second batch went sideways, I cooled the pot, emptied it again and scraped it out. Thinking I had picked up a few weights that I hadn't checked, I pinched every single weight that went into the third batch, but no dice. Still turned to mush about halfway into the melt.
What gives? I'm using a Dutch oven that yields 40-50 pounds when filled, and tested every single weight this last time. Any thoughts on how this is happening? Could there be enough zinc left on the slotted spoon/stirring stick/pot to poison a 20-lb pot? Is there anything else that would resemble zinc contamination, too hot, too cold, adding too much cold lead at a time, etc? I appreciate any ideas.