I've got a question on the exuast. It's 3.5" hole in the back of smoker and thinking it's a little small. I'm thinking of stepping up to 4" after 10 " - 12" or so and going long with it like 3-3.5'. What do you guys think?smoker is right about 55 to 60 gallons
I had to go back and look at the dimensions of your build. A 3.5" exhaust will be fine in my opinion because you are working with more of a vertical build rather than horizontal draft. I would keep the length to around 6" to 12" tall to minimize any stall as Ahumadora mentioned.
I'm worried the heat will not wanna get out good enough and that I will have to have a tiny fire. It's all stainless and insulated. Got some more work done on the smoker today but can't load pics. I see a lot of guys on here even using 6" stack on similar sized cookers as mine.
The heat/smoke traveling through the pipe to the chamber is a bigger concern to me than the 3.5" exhaust. If your'e concerned with the exhaust size increase it. You can always cut back on it if needed with a damper.
When the heat /smoke enters the pipe to travel to the chamber my concern would be it cooling down. If the firebox were attached to the cooker and only a short transition I believe it would work better. The set up you are working with is common in smoke houses but they cook at much lower temps. It may work fine it is just a concern i would have.
Ok thanks. I really don't think that will be a concern. My firebox is fully insulated with insulating 2300 brick and the tubes are 1/4 stainless. Stainless does not dissapate heat well at all. Mild steel steel dissipates about 5.5x's as quick as stainless steel does. I maybe just weld in a 3.5" cookie and place it in the hole and tack it then I'll have a pilot again to use 4" whole saw. And that way I think I'll be able to have a bigger fire that will be easier to keep going for a while. Again thanks a lot for your advise.
I'm planing on just using 3.5" exuast stepped to 4" or I found about 4.250 today but passed. Got one of my racks built. 3/4 1/16 frame and 1/8" dubler and some angle some 3/8 also cross bars and 3/16 across the top. It's pretty stout