I have drilled 3/4" holes at the bottom and in the top for my airflow. I'm planning on using 3/4" black pipe 90 degree Street Elbows with plugs, pipes and brass ballcock valves to control the air. The problem I'm having is getting them tight into the drum, I have tried to use the electrical box type nuts and they seem to keep slipping, I went to a plumbing supply house looking fro something and they said the black pipe thread design is tapered so you typically can't put nuts on them and draw them done tight to the barrel. So how are other getting those tight? Thanks Much BIGDAN1122 will have to post some pics in next post, getting close to doing a test burn, still needing to make a firebasket, had an idea I took t the welding shop and they wanted over $300 to do it so on to plan B Here are a couple of Pics Still need to: install Handles to lid and barrel, Install Temp gauge, think I might put it on 4 casters, straps for pipes, going to add a little hook to lid so it can hang on lip of Barrel when open , deciding on the fire bin, might give it a name with a stencil or something. I think I'm going to try and solve my problem mentioned above by using a 3/4" long threaded nipple, 2 3/4" couplers and fill in the slack on the inside with the electrical box style nuts I have to tighten it up, will take a Picture, post later and let you all know if it worked. Here are a couple of pictures of the coupler Setup I put together for the Air inlets, think I'll only have to use the on the 90's that are holding the pipes and BrassBallCock Valves I did try it on the drum and it will really tighten down.