This is a casting pot I have been working on and off for a while...actually more off than on, but that's how a lot of projects go at times. The main chamber is a 6" piece of pipe 4" long with a ceramic heater off McMaster around it for heating. The main pot is controlled with a probe style TC mounted under neath the bottom plate so it only contacts the lead. I wanted it to read the lead temperature more than an area around the heater. That is also why I went with the ceramic heater so it could handle the overshot when it starts up sense the sensor is away from the heater.
The valve is a 1/4 turn valve so that crud in the valve will be cut off and will not be able to float up the valve and hold it open.
http://www.youtube.com/watch?v=rs0iIF7Tqfw