THE X-400 PIT

The X-400 (Experimental, 400 lb. capacity) was built to test the scalability of Karubecue technology to commercially-sized cookers.  It was constructed and tested in the Fall of 2008, with excellent results.

Like the C-60, the X-400 is modular in construction:

1. A 290 lb Inverted Flame Firebox (IFF) is constructed of 8" junior channel steel.  It accomodates full-sized logs.
   
   

   A look at the X-400's Inverted Flame Firebox

   
   
   
2. The cookbox is a refurbished Friedrich Max Flavor 400.  Significant modifications included the removal of self-cleaning plumbing, reversal of the airflow, replacement of all controls, and disabling of the electric heating elements.
   
   

   Loading the cookbox of the X-400 with pork butts

   
   
   
3. The AutoDraft controls are based on a 1/4 DIN temperature controller and a high-temperature blower with variable suction bypass.  The exhaust is the square hole in the right door panel in the head-on view.  Here's the circuit diagram.
   
   
4. A stock 5x12 tandem trailer was fitted - it pulls nicely despite having the aerodynamic properties of a phone booth.
   
   
5. The existing convection fan was retained, and was so successful it served as the basis for the convection fan now designed into the C-60.  Full loads of 15-17 lb briskets were finishing in 12 hours at 235F with this improved heat transfer.