I am using a piece of 20in 3/8 wall pipe for the cooking chamber, It It will be 36in long. The firebox will be made of 14i 3/8 n x 24 pipe. I understand that the channel plate should mount 3-4in under the cooking grate. It will have a drain to allow the drippings to exit the cooking chamber. It will have a 4in stak. I am still debating on how close to mount it to the grate. The heavy wall pipe is a question that I have. Some of you that have used old propane tanks etc. Let me know how the heavy gauge material preformed on long cooks. Also let me know how hard it was to maintain temps. I want to thank all of you in advance for your help.