I found a New Braunsfels smoker on CL for $50. It's been used 3 times to cook steaks, it was kept outside with a cover then eventually in the garage. The metal is in good shape, no rust holes but the bottom shelf is dented. This thing hasn't been used enough to call it seasoned.
I fired it up and threw in some wood chips to check how bad it leaks and holds temp. I wasn't impressed so I started looking for mods and noticed that this fire box is about 2" higher than some of the better models. So I had to start making changes.
I picked up some 3/16" plate and started marking it out for a lower fire box and a smaller fire box to cooking chamber opening. I used a few of the pit calculators to determine the intake and exhaust opening and if that doesn't work I'll make changes later. I pulled it apart and here's where I'm at right now.
You can see the outlet from the fire box is at grill level and that makes a very hot spot so that part of the smoker is useless, maybe a water pan there would help but I'm going for better results.
Here's the mounting plate, you can see how much smaller I'm making the outlet for the fire box. It's 4" x 9" and should work better with a nice even flow compared to wide open burning charcoal/wood like crazy. When I tested it I used 5lbs of charcoal and it burned for about 2 hours with the temp over 300 for most of that time. I'm sure the ash door leaks had something to do with that.
I saw these in the store and bought 3 packs. The price was so low I thought if all else fails I can make broth but I since learned from some Youtubes that these are awesome if cooked like a brisket. There's probably as much bones as meat but it's that good ribeye meat you get when you cook a bone in rib roast. Low and slow for 2.5 hours then wrap and another 1.5 and finally unwrapped for a little more color and set the crust. Guess what I'm doing now?