vertical gravity build question

I've seen these stumps clones built like the pic above with a fuel tube straight into the ash box and the fire in the bottom of the tube; and where the tube dumps into a fire box and then dumps into the ash box below.

Is there an advantage to separating the fire from the feed tube? Was planning on 1/4" for the box and tube, 8*8*10 box and the tube will shrink to 6*6 at the top

This will be a smaller cooker food chamber will be 18*24*36-wish

Thanks!

Hawg Father of Seoul said:

Dude, many have tried to improve that design. No one has yet.

Click to expand...

Don't want to improve anything, trying to keep this as simple as possible. Just need to figure out what design is the design.