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Help on a smoker build

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Hey all, been a while since I have asked anything on here. Looking for some help with my first smoker build. Im using a 120 gallon scrap propane tank, does anyone know how to calculate the stack? Firebox size and opening to cook chamber? Do you recommend reverse flow? Or should I just do a offset? Why? Does this change the size of anything? Any help would be much appreciated. Last time i posted i asked something similar. I saw how to calculate the opening but that was for offset and im not sure if that changes anything or not. Finally getting to the build now. Have the tank ready amd cut the door out so hoping to have it done soon.
 
Yep.. everything you need to know right here... I built mine to the exact numbers the calculator put out and works like a charm... My build is in my signature line below...

This is the calculator...

 
Hey all, been a while since I have asked anything on here. Looking for some help with my first smoker build. Im using a 120 gallon scrap propane tank, does anyone know how to calculate the stack? Firebox size and opening to cook chamber? Do you recommend reverse flow? Or should I just do a offset? Why? Does this change the size of anything? Any help would be much appreciated. Last time i posted i asked something similar. I saw how to calculate the opening but that was for offset and im not sure if that changes anything or not. Finally getting to the build now. Have the tank ready amd cut the door out so hoping to have it done soon.

Afternoon Friend!

I haven't built a traditional offset, but have built a reverse flow. My understanding is, the dimensions for each is about the same. Here's a handy online calculator that I've used a time or two:


Red
 
Yep.. everything you need to know right here... I built mine to the exact numbers the calculator put out and works like a charm... My build is in my signature line below...

This is the calculator...

Thanks. Will also take a look at this.
 
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in for the pics
 
I never used the calculators (didn't know they existed) when I build my reverse flow.

A mate of mine built one years ago and started with the baffle at 1/3 of the smoke chamber and he said it wasn't ideal. He then modified it to be 1/4 and it works great now.

I took that on board and did the same. I also did a test burn with the baffle just sitting in position before welding it in just to confirm good draw etc.
 
That’s really useful advice, especially doing a test burn before welding the baffle permanently. Being able to make adjustments at that stage seems like a smart way to avoid problems later. Thanks for sharing your experience—it definitely gives me a few things to consider for my own build.
FWIW, I just realised that I wrote that around the wrong way.

Should be "A mate of mine built one years ago and started with the baffle at 1/4 of the smoke chamber and he said it wasn't ideal. He then modified it to be 1/3 and it works great now."

The original baffle I cut and trial fitted was similar (around 1/4). Without even welding it in I made a bigger baffle and then did a test burn.

Wasn't sure what I was looking for burn wise but figured if the wood caught alight easily and burnt fast and with open dampers then it was probably about right.

Depensing on your design you can further change airflow by changing the size of the mesh/grate that your fire will be burning on. My smoker for example has the firebox damper underneath the grate so as the coals burn down they fall out the damper holes. I trialed smaller mesh grates which greatly affected how well the fire breathed.

Ultimately, I settled on some stainless steel mesh with approximately 15mm square holes...
 
Also, the V shaped fire baskets is where it's at... Keeps all your coals more concentrated and therefore lites the split quicker.. Which actually helps conserve fuel as well...
Great tip, now I need to make a conical fire basket to try in my round firebox
 
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