After the burner modifications, I had the lead melted in 40 minutes, and ingots poured in around one hour from startup, from about 80 kg or 200 pounds of scrap.

The insulation worked very well, and although most people don't insulate their melter, it proved useful to do so.

After all the scrap was melted, the melter sprung a small leak in the welding around the nozzle, which started dripping onto the burner, so I turned off the gas. I was able to pour all these ingots with the burner off, and there was only about 1.5cm / 0.5 inch deep left in the melter before it cooled too much to flow.