I plain on the mail box mod to be only air intake.
My question is how big of exhaust i need. Do i need a 4" exhuast or would 1" be enough.
I am sure i will have more questions, but this will get me going on the build.
Thanks for input.
Hello. Welcome. I see this is your first post. Please take some time and swing over to Roll Call and introduce yourself so that we may give you a proper "Hello". All info you can provide us with such as smoker type, location and so on will help us answer any questions you may have, and pictures help a bunch. As for your question:
There are many folks on here who can give you EXACT dimensions. I have built a few smokers in the past. I ALWAYS overbuild. My "theory" is build it in at the beginning and not need it rather than tear it apart later to add it and screw up the paint job. SO for me I would have a 4" exhaust AND two 2" intakes in the build. Make them all damper controlled in some way. You probably won't need that BUT, what if you do? I even plan a fan to force air into my fridge build in case I need it for cold smoking. Just my ramblings. Hopefully some one less crazy will offer advice. Keep Smokin!
If you're using wood or charcoal for heat, I would go with a 4" exhaust. For electric, I don't think you need that much convection, in my unscientific opinion. Seems like you would be losing a lot of heat with one that size.
Mine is somewhat larger, and a 1-1/2" exhaust works fine on it.