I finally broke down and purchased a 28.00 PID, SCR and thermocouple from ebay, 28.00 shipped. Modified my manual infinite dial controlled oven to a digital one. Works great I know its not really a knife and I posted it in the knife section, but I thought there may be people running old Kilns out there with dials or manual controls and this solution was very reasonable priced and works great. I kept the K type thermocouple that came with the oven, it drove a meter that has been replaced with a Digital PID
I'm going to get a couple more and modify my cheep toaster ovens to get a higher quality more stable temperature.