David:

I think you need to use a round pot that is shaped the same as the burner and doesn't waste the heat.........Watch the Nitre Blue video again...... Your burner looks big enough to me.....

Doesn't look like the 'stump stuff' is melting quite right...?..........

Clean/cool the parts in a bucket of water, polish and then oil the parts after they are clean and cool (I wax mine).

Hope this helps.....

Best,

Doug