The Texas BBQ Forum

Wow, what a cache of information there is on this forum! I am in the planning stages of building my smoker out of a 500g propane tank. I have a bunch of question so its hard to know where to start, but here goes. I'm trying to nail down as much as I can because it seems like if you change "this" then it changes "that". I guess if someone could give me a hard and fast starting point that would help. I know Feldon's calculator starts with tank size and goes from there to FB volume. But the dimensions of that can vary a lot. And that leads into FB placement on the tank(how high or low on the tank) which in turn leads me to half moon size of opening from FB to CC, does it make a difference how wide it is? If its wider then it doesn't have to have as tall of a bridge. But do I want that opening within a certain distance of the first food grate? Which, by the way, I was planning on placing in the middle of the tank. I guess Ill start right there and see where this goes. Any guidance and info is much appreciated!

Welcome to TBBQF - there should be someone come by here and help you. Why don't you also go over to the New members Forum and introduce yourself.

Thanks Rambo Ill see if I can find my way over!

I'm thinking the wider my half moon opening is and lower in the CC, the more evenly smoke and heat will flow in. How is my thinking flawed?

**crickets**

Also, is there a standard for how far my FB is set into my CC? Im not planning on cutting the round off the CC at the FB end, just cutting the opening for the FB itself.

There is a calculator on one of these threads that guides you on the fire box size and opening. Maybe KAM will see this and weigh in on it. There is also an email adddress on that calculator that is linked to KAM i believe. Good luck on your build.

Thanks GRailsback! Ive been hoping KAM would drop in. It looks like he really knows his stuff. Ive played around on Feldons a bit but I have a few questions in my mind that keep me from nailing down a firebox size there. Perhaps Im overthinking it? I know I want a half moon opening from FB to CC but the calculator doesn't give you an opening size till you put in the dimensions of your firebox. But Im not certain on dimensions yet because Im not certain on the placement of the FB on the end of the CC. I know I want the FB to be the same width as the tank where they meet. I see KAM said on one thread he liked his bottom grate to be about 6" above his RF plate or tuning plates. Does placement of the half moon on the FB wall matter as far as how high or low it is oriented? Hopefully this sheds some light on my layout conundrum. I just want to make sure I have taken all factors into account before I start cutting.

Yes he is very knowledgeable. And he usually keeps an eye on that category on here. But you may want to send him and email just in case he doesn't get on here for awhile. I am not much help when it comes to sizing the firebox or anything.

Right on. Perhaps I'll drop him a message.

Any suggestions on the best way to get accurate lines on the end of the tank for the FB cutout would be welcomed. Maybe its optical illusions, but I'm having a hard time trusting what I have layed out. Thanks!

Got my tank cut open this afternoon! We're making progress! I was surprised to find a steel ring in behind each weld where the end caps are attached.

Oops! Posted the wrong pic above! Now she's really open!

Mainelytxs wrote:Wow, what a cache of information there is on this forum! I am in the planning stages of building my smoker out of a 500g propane tank. I have a bunch of question so its hard to know where to start, but here goes. I'm trying to nail down as much as I can because it seems like if you change "this" then it changes "that". I guess if someone could give me a hard and fast starting point that would help. I know Feldon's calculator starts with tank size and goes from there to FB volume. But the dimensions of that can vary a lot. And that leads into FB placement on the tank(how high or low on the tank) which in turn leads me to half moon size of opening from FB to CC, does it make a difference how wide it is? If its wider then it doesn't have to have as tall of a bridge. But do I want that opening within a certain distance of the first food grate? Which, by the way, I was planning on placing in the middle of the tank. I guess Ill start right there and see where this goes. Any guidance and info is much appreciated!

Are you building a conventional smoker like tuning plates or are you building a reverse flow?
What size firebox and exhaust size are you planning?
I apologize for not seeing this I have been fairly busy and not much forum time.

No worries k.a.m.! Life happens! I'm planning a conventional with tuning plates. Is it possible to get away without tuning plates? I'm thinking 10" stack but open to any pros and cons. I think the FB is going to be about 40-41" wide. That's the width of the tank where they will meet. I'm playing with the other numbers(H,L) to get the volume I need and a size that works best for me on a trailer. Is there a ratio that seems to work best? The other part of the FB size decision is the half moon size seems to vary when I play with the numbers on Feldons. I'll stop there for the sake of not overloading you with info and see what we come up with. Thanks so much for stopping by and totally respect your willingness to help us rookie builders out!!

Mainelytxs wrote:No worries k.a.m.! Life happens! I'm planning a conventional with tuning plates. Is it possible to get away without tuning plates? I'm thinking 10" stack but open to any pros and cons. I think the FB is going to be about 40-41" wide. That's the width of the tank where they will meet. I'm playing with the other numbers(H,L) to get the volume I need and a size that works best for me on a trailer. Is there a ratio that seems to work best? The other part of the FB size decision is the half moon size seems to vary when I play with the numbers on Feldons. I'll stop there for the sake of not overloading you with info and see what we come up with. Thanks so much for stopping by and totally respect your willingness to help us rookie builders out!!

I would put the tuning plate rails in and try the cooker without them then if you feel you need them its only a matter of building the plates and dropping them in.
The 10" exhaust would be my choice.
I prefer my fireboxes to be 115% to 125% larger than needed.
Here is a link that you can use to apply the opening using the pit calculators numbers. You can also use a trapezoid opening if you chose.
https://planetcalc.com/5155/