This post looks more in depth into the problem of inefficient thermal insulation and how you can improve the efficiency of your tunnel oven
Curing Tunnel Oven, Drying Oven
AggSound 157mil 18sqft Roll Pack Universal Sound Deadener for Cars
Yet Another Reflow Oven
How To: Whirlpool/KitchenAid/Maytag Oven Insulation WPW10208653
Yet Another Reflow Oven
Woll Concept Plus Multi-Function Collapsible Silicone
Non-Stick Oven Liner Reusable Spill Mat Teflon Baking Aide
Used Sold Thermo Lab-Line 6258 Upgraded Vacuum Oven - 0.7 Cu-Ft at
Industrial Hybrid Tunnel Oven