I am planning several rocket burners for different things. My question is, has a long feed tube been tried with a cap? Feed into the burn chamber from above, fire distance correct from secondary combustion chamber, but long tube and cap it, let the air in like a tunnel feed type thing? Wouldn't the cap let longer material be used without being able to chimney? I've seen all the arguments for short feeds and understand, like the idea of slanting a long tube both for ease of loading and "flow" of material into the fire. Still makes me think a longer time between loading could be achieved by capping the tube... Newbie here, just starting to play with this, you don't have to be gentle... LOL