Need help with sizing...

[Dir-T-Birds]

Hello, Im planning a reverse flow trailer build using a lang model 60 with warmer as a reference. 24" diameter pipe, 5' long with a 24" dia. by 24" long firebox. My questions are, how big does the hole between the firebox and the chamber need to be? How much clearance can there be between the baffle and the cooking grate? How big does the gap between the end of the baffle and the chamber need to be?

I plan on using 4" pipe for the stack, will 4' be long enough? How big does the hole between the horizontal chamber and the warmer/vertical smoker need to be? Can this hole be at approximately grate level in the main chamber without causing (stagnant?) problems? Thanks for any and all help.

[Frank_Cox]

Welcome to the site!!!!!
I will send you a PM about sizing for your smoker

[SimplexCoda]

I have the same exact questions. Im using a 155 gallon propane tank for the cooking chamber. My other question was how big would the gap at the end of the baffle opposite the fire box need to be. I was considering putting a damper in it so that it could be adjusted.

[Frank_Cox]

I will send you a PM .

[smc51]

gee, I was looking forward to some good information about these guys builds.

[Frank_Cox]

I need to find time to finish the blog post about the baffle plate and stack etc. I just have been too busy to finish it up. Hopefully soon I will get to it.

Sent from my iPad using Forum Runner

[k.a.m.]

Dir-T-Birds, here are the numbers I came up with based on your dimensions and if I am correct in that your using pipe for your firebox.
A 4" ID stack of 43.20 in.
You will need 33 Sq.in of intake opening.
Your firebox to cooking chamber opening will need to be 87 Sq.in. A half moon cut 15" x 7.5" will give you approximately 88 Sq. in.
You want the R/F plate opening opposite the firebox to at least equal your firebox to cooking chamber opening.
The clearance between the R/F plate and lower grate can be as close as 1" or as far as 5". A Lang starts out at 1" on the firebox side and falls approximately 3'' away from the firebox. I built mine with a 4" clearance and a 1" fall making the far end right at 5". I hope this helps.