The charcoal basket of the Red Box Smoker is just plain terribly designed. Even with the charcoal insert, there is terrible air flow and a good possibility that the charcoal will get snuffed out by sitting in its own ashes.
Another issue, if you are using the stock water pan, is that the included water pan is too deep to allow for loading up the stock charcoal basket. Loading up the stock charcoal basket only compounds the already existing ash buildup problem described above. If you get a more shallow pan (the water pan is just a "steamer" pan sold in restaurant supply stores or Amazon), then your water will run out after a couple of hours because it bubbling too much.
Fortunately, it's pretty easy to solve both problems. I made a new taller charcoal basket by turning the included insert upside down and then using expanded metal to raise the walls. I added 1.25" SS screws for the legs and I got a 9"x13" baking at Marshalls ($3.99) to catch the ashes. You will need to bend the lip of the baking pan to make it fit. Capacity, air flow, and ash buildup problem solved.
I replaced the stock water pan (it's a 1/2 size, 4" deep steamer pan) with a 1/2 size, 2.5" deep steamer pan. This gives me room underneath for the taller charcoal basket, plus and more importantly, a simple heat diverter. The heat diverter is simply a 12"x12" 22ga. plain piece of metal I got from Home Depot. It cost $7.98 and it fits perfectly (no cutting required) right on top of the modded charcoal basket. This will give you an air gap just like how the Backwood Smokers have.
I've only used this setup twice and both times it worked great. The water in the pan no longer boils like it did before and the charcoal lasted much longer and burned more evenly. Here are the pics - the modded basket with and without the diverter.
Another issue, if you are using the stock water pan, is that the included water pan is too deep to allow for loading up the stock charcoal basket. Loading up the stock charcoal basket only compounds the already existing ash buildup problem described above. If you get a more shallow pan (the water pan is just a "steamer" pan sold in restaurant supply stores or Amazon), then your water will run out after a couple of hours because it bubbling too much.
Fortunately, it's pretty easy to solve both problems. I made a new taller charcoal basket by turning the included insert upside down and then using expanded metal to raise the walls. I added 1.25" SS screws for the legs and I got a 9"x13" baking at Marshalls ($3.99) to catch the ashes. You will need to bend the lip of the baking pan to make it fit. Capacity, air flow, and ash buildup problem solved.
I replaced the stock water pan (it's a 1/2 size, 4" deep steamer pan) with a 1/2 size, 2.5" deep steamer pan. This gives me room underneath for the taller charcoal basket, plus and more importantly, a simple heat diverter. The heat diverter is simply a 12"x12" 22ga. plain piece of metal I got from Home Depot. It cost $7.98 and it fits perfectly (no cutting required) right on top of the modded charcoal basket. This will give you an air gap just like how the Backwood Smokers have.
I've only used this setup twice and both times it worked great. The water in the pan no longer boils like it did before and the charcoal lasted much longer and burned more evenly. Here are the pics - the modded basket with and without the diverter.
