SD, afternoon......
FB/CC opening...... 62.4 sq. in. x 1.5 = approx 92 sq. in.
radius = 11.75"
Segment Area = 87.35
seg. ht. = 6"
chord AB = 20.49"
Opening at the end of the RF plate 7" plus for extra room and reduced friction...
I think where we screwed up is...... I use the size of the CC as the primary for doing all the other calculations..... The CC has no idea if the FB is made larger... Same with the exhaust stack and FB air inlets......
Sooooooo... I enter the CC size and note the recommended sizes for the other variables.... Calculate the FB/CC opening, Exhaust stack, FB air inlets all from the recommended numbers for the size CC entered into the calculation... That includes the recommended FB size....
Since the CC works well with the recommended sizes, making them larger won't affect the cooking ability..... Raising the RF plate and enlarging the FB/CC opening won't affect the cooking ability of the CC... It will affect how the smoker breathes and reduces the over temp problems with the FB thus reducing fuel consumption, especially if an additional air inlet is installed directly across from the FB/CC opening...
taken from Feldon's calc.... I used the recommended FB size from the original calc. using the CC volume to plug in the equation below...
Recommended Firebox-to-Cooker
Opening Area
(firebox volume * .008)
square in.
Below is how I determine what sizes are appropriate for a smoker..... Then change the FB size if you want, change anything you want... but the CC can't be changed and the numbers below are what's necessary for the CC to work.... I changed the RF plate number some time back, and added an additional "above the fire grate" air inlet to help cool the FB and improve fuel consumption......
Link to BBQ Pit Calculator
You think reading my ideas, put in print, is confusing.... Try pulling it out of my head and putting it onto paper.... That's the tough part....
Let me know how bad I confused you and I will do my best to straighten out what I screwed up.....
Dave
