Hey, I am in the process of building a smoker and would like to run my numbers by you guys for plan confirmation. In general I am planning a RF offset cooker with an insulated firebox and an insulated warmer (on top of the box with vents to the warmer from the cc and the fb. Basically the same as a Shirley type design)
Smoker Body: 120 gallon propane tank. End cut off and tank shortened slightly to give a CC volume of 90.5 gallons (20898.6 in^3)
Firebox: cube firebox insulated. Planning 3/8” steel and inside dimensions of 20” x 20” x 24” long. Volume is 9600 in^3 and is high according to the tutorial and Feldons. My thought is to build it large so that it has capacity for both the cc and warmer… I could "reduce the volume" by raising the cooking grate or adding bricks. ?
FB/CC opening: Since my FB is 20” wide on the inside, I plan on a half moon with a top chord of 20” and a rectangle on top. The chord area will be 73 and the 1.5x20” rectangle will be 30. So the total opening area is 103 in^2. The tutorial suggests cc volume x 0.004 = 83.6 in^2 but it sounds like there is another factor of up to 1.5 that may be used…
RF plate: To simplify cutting, my RF plate will be 22” wide giving a chord area of 114.24 in^2. Other options = 21.5” wide for area of 106.4 in^2 or 21” with an area of 95.5 in^3. Note that my FB opening if I keep the 103in^2 plan will have the top of the hole 6.75 in above the bottom of the chamber. Is there an advantage to have a step in height between the top of the FB hole and the RF baffle plate? The 22” wide plate gives a height of 7.5 so there will be a 0.75 in step, the 21.5” gives a continuous height.
End of firebox will maintain the area under the plate
Now for the warmer, should I maintain the FB/CC area for the CC to Warmer passthrough?
Currently I am planning for a warmer that would have a similar volume to the CC (18000 in^3) I would like this to be able to maintain the same temp as the cc, should I leave the top of my fb uninsulated? If I plan to have cooking that will sometimes ONLY use the warmer, should the vent from the FB to warmer be the same as FB to CC? Remember that the warmer will be insulated except the wall between the cc and fb
Smoker Body: 120 gallon propane tank. End cut off and tank shortened slightly to give a CC volume of 90.5 gallons (20898.6 in^3)
Firebox: cube firebox insulated. Planning 3/8” steel and inside dimensions of 20” x 20” x 24” long. Volume is 9600 in^3 and is high according to the tutorial and Feldons. My thought is to build it large so that it has capacity for both the cc and warmer… I could "reduce the volume" by raising the cooking grate or adding bricks. ?
FB/CC opening: Since my FB is 20” wide on the inside, I plan on a half moon with a top chord of 20” and a rectangle on top. The chord area will be 73 and the 1.5x20” rectangle will be 30. So the total opening area is 103 in^2. The tutorial suggests cc volume x 0.004 = 83.6 in^2 but it sounds like there is another factor of up to 1.5 that may be used…
RF plate: To simplify cutting, my RF plate will be 22” wide giving a chord area of 114.24 in^2. Other options = 21.5” wide for area of 106.4 in^2 or 21” with an area of 95.5 in^3. Note that my FB opening if I keep the 103in^2 plan will have the top of the hole 6.75 in above the bottom of the chamber. Is there an advantage to have a step in height between the top of the FB hole and the RF baffle plate? The 22” wide plate gives a height of 7.5 so there will be a 0.75 in step, the 21.5” gives a continuous height.
End of firebox will maintain the area under the plate
Now for the warmer, should I maintain the FB/CC area for the CC to Warmer passthrough?
Currently I am planning for a warmer that would have a similar volume to the CC (18000 in^3) I would like this to be able to maintain the same temp as the cc, should I leave the top of my fb uninsulated? If I plan to have cooking that will sometimes ONLY use the warmer, should the vent from the FB to warmer be the same as FB to CC? Remember that the warmer will be insulated except the wall between the cc and fb