I have researched and have found a couple different smoker designs in this forum so I have built a smoker by combining a couple different plans and added small tweaks of my own.
My smoker is 36" wide x 30" deep and the main body is 60" tall.
The following is the progression of the smoker build.
I purchased and cut 11 gauge 2 x 2 square tubing
I welded the frame together.
This is where I have added my own twist, I have seen the smokers with a channel in the back, I have seen them with channels on the side so I thought lets do both. I welded frame in for the top of the firebox leaving 2" gap in the back and 1" on both sides. I welded a 1/2" piece of steel for the top fire box. If you notice I have my door frames welded out of 1" square tubing and just set in place.