Planning a Reverse Flow (Calculator help)...

[bruno994]

I am in the beginning stages of my 150 gallon reverse flow trailer build.  I have used the BBQ Calculator http://www.feldoncentral.com/bbqcalculator.html  to start my planning.  But since I am building a reverse flow, what are the main differences I need to take into effect and what calculations need to be adjusted?  Thanks for any and all input from everyone.  I have gotten so many ideas from this forum reading through all the other build threads.

 

[daveomak]

bruno, morning....  The folks who put this calculator together (Alien), did a lot of research and calculating, to provide a good tool to get the build correct...

If you have concerns as to whether or not it will work for your build, the firebox to cooking chamber size is one I would use.....

As far as openings, you could increase the firebox/cooking chamber opening by 10% and the same for the exhaust stack numbers.... 

That being said, if you build the smoker per the calculator and leave room for the FB/CC opening to be enlarged I would do that....

The exhaust stack dimensions... you could always add length to the stack to increase it's dimensions at a later date...

Inlet to the firebox, you could add 10% to that also, or leave room to enlarge the holes at a later date.... 

Trying to build a perfect smoker on the first go around is pretty close to impossible... This calculator will give you a very good start...

I think most folks here have altered their smokers at least once to make improvements to their liking....

I notice the opening dimension at the end of the reverse flow plate is not given....

Solaryellow has given that dimension on his build post....

Since the smoke/air/heat has to take a 180deg turn at the end of the reverse flow plate, I would make it at least 2 x's the FB/CC opening size... and leave room to make it larger.... Just a guess.... no facts....

I would start with the calculator numbers and leave room to adjust the 3 dimensions at a later date, if needed....  

Dave

 

[bruno994]

Thanks for the info Dave.  I must have misunderstood on the opening on the end of your reverse flow plate needed to be at least as big as your opening from the firebox to the chamber.  I will reread his thread again.  The tank is a 150 gallon air tank out of commission at my pallet mill.  It is a Manchester Tank model, with 33256.2 cu. in of volume (just slightly under 150 gallon actually).  Planning on 6" stack (25"), 24 x 24 x 24 (13824 cu. in.) firebox, a bit big, but I would rather go big now on the firebox (recommended- 11550 cu. in.).  6 three inch round air intakes on the firebox, 3 on each side.  With a 6 x 18 opening from firebox to chamber and at the end of the reverse flow plate.  I am up for any and all suggestions.  I am getting ready for a few small comps in early summer and I really need the upgrade in cooking area.  Thanks again Dave.   

 

[bnew17]

Bruno,,,i was under the assumption that the opening from Firebox to Cook Chamber should equal that of the opening at the end of the reverse flow plate as well? I have not started my build yet. It will be a 250 rf , i plan on starting in the next month or so.

 

[done-deal]

I can't get the calculator to work for the Firebox-to-Cook Chamber Opening?

I enter the Cooker Chamber Type & Size and I get the Calculations for that, but I need to know the opening for the other.

I'm building a 18"x36" RF.  Any help?

 

 

[daveomak]

Done-Deal, evening and welcome to the forum....  your post got lost in this old thread.... Please start a new thread and post your question in Reverse flow builds......  http://www.smokingmeatforums.com/f/201/reverse-flow   and please stop in and introduce yourself for a proper welcome....  http://www.smokingmeatforums.com/f/133/roll-call  .... Again, sorry your post got lost in the shuffle..... stuff happens around here...  If you need any help with anything, you can always PM me and I'll help where I can....   sometimes it takes awhile for me to get back to the 'puter but I will return.....  Dave  PS: I can help with the calculator.....