Are you building from the plans (smokerplans.net)? Or are you winging it from pictures etc? I'd say most of the guys on this site have built gravity feed smokers from the plans. And as far as I know there are no calculators for gravity feed smokers... I might be wrong, but I've not found any.
Learning generally boils down to "Repetition or the avoidance of pain", some people learn by doing, some by watching and some just have to pee on the electric fence.
Whether you think that you can, or that you can't, you are usually right. Henry Ford
It is all about the charcoal burner (BTU) vs the cubic inches of the CC. Frank might answer your question on a PM. But I personally recommend the plans for this one type of smoker.
Current Smokers: Backyard RF Offset and Hybrid RF Offset trailer rig with Cowboy cooker and fish fryer, always room for more........
I have bought plans but i want to make some modifications. i am converting it all into metric for myself before i start building as inches are confusing for me, most material in uk is sold in metric too so it will just be easier. I am tweaking some aspects of the design to add a few features that i would like and the CC size is going to be slightly different to the plans and i just want to know what calculations to run through to make sure the burner is still the correct size to cope. If its just a case of using the ratio of burn vol to cc vol in the plans i have then i will go by that but i would like one of the pros to confirm for me before i start pouring cash into it.
According to Frank you can make the CC a tad bigger than the plans and it will be OK. The figure 125% springs to mind, but I might be wrong. Check with Frank.
Learning generally boils down to "Repetition or the avoidance of pain", some people learn by doing, some by watching and some just have to pee on the electric fence.
Whether you think that you can, or that you can't, you are usually right. Henry Ford