I have just arranged to get a length of 30" dia. 3/8" thick wall pipe to make a horizontal reverse flow smoker with. Now I have a multitude of questions. I am planning on 30" diameter by 48" long smoke chamber. The firebox will be 22" x 22" x 24"long with 35 sq. inches of intake and a transfer opening of 92.93 sq. inches. The smoke stack (4") will need to be at least 46.24 inches high above the point where it comes out of the smoke chamber. I apologize if I am asking questions that have already been answered a bunch of times.
- I have read on this forum about the BBQ calculator and have done the calculations to come up with the firebox size, intake, transfer opening, and exhaust length. I'm good with that, but when I start looking at smokers designed and built by reputable businesses (some even mentioned on this forum as being good ones) I can see that they don't follow the same calculations on their smokers....by a long shot! At what point does the firebox NOT need to be 1/3 the volume of the smoke chamber? I am going to assume the need arose for adequate wood ash storage under the grate and adequate room to place wood in the firebox.... Then adequate volume to reduce ash flow into the smoke chamber and onto the meat.... The guys who designed the original smokers and came up with the calculator are pretty dedicated to their hobby....
- They also cut back on the size / length of the smoke stack. I'm ok with my 4" stack at 46.24" but I've read different ideas on whether it should extend all the way down to the cooking rack or just be flush with the inside of the smoking chamber. Is that just a matter of preference or will one work better than the other? The stack needs to be measured from the top of the smoke chamber for proper air flow.... The idea of adding a section to lower the intake to just above (3"-4") the cooking grate is to keep the heated air in the chamber above the cooking grate while drawing the "new" smoke and heat across the food.... This essentially makes a convection type effect on the meat... before the extension was installed, the meat sat in a "dead air zone" of no air flow and took longer to cook....
- Can the RF plate act as the bottom of the water pan or, unlike my ECB, does a RF smoker need a water pan or just a drip pan? Several folks here install their RF plate gently sloped away from the firebox and with a welded in piece of steel strap on the non firebox end to form a dam.... The RF plate has a crease or piece of angle welded in the middle... the Rf plate also slopes toward the center of the long dimension... At the dam end, a pipe is welded in the RF plate and extends downward and out through the bottom of the smoke chamber and a gate valve is installed... this is where the grease runs into a bucket of sorts... the pipe should be of sufficient size that it does not readily plug from grease and scraps of food.... Water can be placed in and on the RF plate... Doing so will help keep the drain from plugging as grease floats on water and will also act as a water/steam pan... You might consider a drain in the main smoker body also to drain water etc. when cleaning it out...
- Sunday I TRIED to smoke two butts on my ECB at the same time. I based the expected time for completion on a previous single butt that took approximately 1 hour / pound. I thought that additional time would be required but was unprepared for twice the amount of time. I have a friend who can smoke an entire 75 pound hog in about 8 - 10 hours. Does anyone have any idea what took so long? I smoked them at 225 the entire time. Does a larger smoker like my friend has make the difference? Yes the larger smoker makes a difference and also air flow for the convection effect... The smoke chamber holds X amount of BTU's depending on it's size... The meat cools the air immediately surrounding it.... Heat/Smoke/Air movement increases the efficiency of cooking... 2 roasts = 2 times the cold meat surface.... In stagnant air, the meat will take forever to cook... provide some heated air circulation and the time is significantly reduced.....
Thanks in advance for any help.
Circuit Smoker
