250 gallon propane tank build

[bighoof]

Hey everyone,

Been trying to learn as much as possible and now have a ton of questions...first off I've seen a couple of posts implying the stack length is the measurement above the CC is that correct? So if the calculators tell me I need a 31" stack that is from the top of the cooker? So technically the stack is actually longer if it's from the grate level?

Firebox so far in theory is a 24"x36" pipe surrounded by a 30'x30" x36" box. Does that sound alright cause feldon says i'm about 84% will that still work? What would the lowest % I'd be allowed to use? But just this morning I visited the local pipe guy he's got just about everything. How concerned should i be with weight? How much more efficient is the the firebox if it's semi insulated? I could get a 30"x27"x1/2" piece of pipe but it'd weigh a ton...especially if i put a 24" piece in side of it. Honestly alittle overwhelmed with all the calculations...don't want to screw nothing up!

Thanks
Jeff from WA

[Rambo]

You’re going to get a lot of answers

[tantrum95]

You have start at some point if you want to finish.

I will only answer one question.

From my experience the Feldon calculator is pretty close so if you are at 84% you would be on the low side. You will have trouble getting the temp to be consistent without adding a fan or some other air source. Also the fire will be really hot to keep up, so you might end up warping your firebox or at a minimum the grate to hold your coals. I have a 250 gallon now and it is pretty much dialed in. I started with a fire box that was too small and it struggled to stay at any temp with constantly adding fuel and air to keep it going. I ended up doubling the size to be 115% of what Feldon indicated and it works great now.

Good Luck! I would like to see some pictures when you get going!

[bighoof]

Thanks tantrum what’s your firebox set up like? Have any pics?

[tantrum95]

Here is the fist smoker that I ended up increasing the size of the stacks from 3" to 5" and 32" tall.. The fire box also doubled in size. This runs like a swiss clock now. as long as I can keep wood in it, this will sit at 200-210 degrees.

[tantrum95]

Here are a couple pic of my first build. It started as a 300 gallon propane tank that I cut down to a 240 gallon cooker.

[k.a.m.]

Hey everyone,

Been trying to learn as much as possible and now have a ton of questions...first off I've seen a couple of posts implying the stack length is the measurement above the CC is that correct? So if the calculators tell me I need a 31" stack that is from the top of the cooker? So technically the stack is actually longer if it's from the grate level?
Measure total length of exhaust. IE your your length is supposed to be 30" you have 8" in the chamber you will have 22" sticking out. Personally all my exhausts start at the top of the cooker and never go to grate level.

Firebox so far in theory is a 24"x36" pipe surrounded by a 30'x30" x36" box. Does that sound alright cause feldon says i'm about 84% will that still work? What would the lowest % I'd be allowed to use? But just this morning I visited the local pipe guy he's got just about everything. How concerned should i be with weight? How much more efficient is the the firebox if it's semi insulated? I could get a 30"x27"x1/2" piece of pipe but it'd weigh a ton...especially if i put a 24" piece in side of it. Honestly alittle overwhelmed with all the calculations...don't want to screw nothing up!
I am guessing you are trying to mimic a Franklin double walled firebox. Personally I would run a single wall the extra weight does nothing for me for the small amount of insulation given but that is just me. I would shoot for no less that 100% if I am building off the calculator. The smaller the firebox the more wood you burn because you have no room for reserve heat/smoke. Basically cold air is entering and exiting hot with no amount of reserve volume.
I hope this helps.

Thanks
Jeff from WA