I am building my first UDS build and want it to be perfect i am a long time bbqer but a novice smoker. I am going to drill the holes for the risers. I am using 1" black iron pipe that we had at work and was wondering if that was ok and is using black iron fittings ok because i know galvanized is not. I just figured more airflow so i might just have to close the valves a little more. Also my drum isnt perfectly round so when i do my burn should i just bend it back in place with a mallet or something? Also is it necessary to put oil inside the drum before smoking? And what is a good dimension for the fire box? I figured i would just get a 18" webber grate and bolt that and the expanded metal together. With the defuser how high above the fire box should it be. Oh and i got lucky we were camping and i happened to find a 22.5" grill lid in the jungle lol perfect timing it sits right on the rim of the drum perfectly except that one spot where its not quite as round. Oh and one more question how high should the bottom of the charcoal grate be above the bottom for good airflow. Thank everyone.