This is my UDS I built last winter. First of all let me say this was very time consuming and would not do it again. But in the end I have a nice smoker that should last. I started with a heavy gauge food grade drum. From there I got a little carried away.
I made a door to tend to the coals if needed and fill the water pan.
I thought it would be nice to have it come apart into two pieces for clean up.
It closes air tight I left it apart in the next pic so you can see I used two pieces of 1/2" flat steel and rolled them, butted them together and welded it.
I made the coal basket and set it up so you could use it as a water smoker or standard UDS.
I put a lot of thought into a drip pan that would not block the direct heat. This is what I came up with. I might have to figure out a way to close off the ends. I will try it first.