Some of the links on this forum allow SMF, at no cost to you, to earn a small commission when you click through and make a purchase. Let me know if you have any questions about this.
Actually a couple questions. How far should my coals be from the CC opening? Is it typical in an OS to need to remove the ash from the firebox during a 4+ hr cook?
Removing the ash from the firebox would depend on much space there is for the ash to build up without sacrificing airflow. As for how close the coals can be to the CC. I used to have mine pretty much right up to the CC. Hope this helps.
IF I remember correctly, on my old Brinkmann, the fire box was set well below the center of the cook chamber and a portion actually hung lower than the cook chamber. The wood/charcoal grate butted right up to the cook chamber. The opening was below the cooking grates and I never emptied ash during a cook. But it did get crowded. Several manufacturers have detailed illustrations of their offset smokers. Have a look around to get ideas.