Firebox Opening

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k.a.m.
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Re: Firebox Opening

Postby k.a.m. » Thu Sep 08, 2016 10:59 am

Damon54 wrote:K.A.M. ,
To be clear my volume is unchanged. My question: Is the area beneath the elevated coal base still relevant to the total volume calculation?? In my case the air inlets are close to fuel grate level.

If you want to get technical if you add solid matter to the inside of a cube it decreases the inside area. In my opinion adding grates to the inside does little to the numbers especially because I oversize my fireboxes slightly anyway. The air space below your grates is relevant to the air needed to pass through your coals to feed the fire. Some folks do not use grates and build their fire on the floor. This is okay if you are burning pretty hot but does not do well with small coal bases.
Always remember slow and steady wins the race.

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Re: Firebox Opening

Postby TX1911 » Thu Sep 08, 2016 11:29 am

As an aside, the folks who made my pit made the opening adjustable. There's a 1/4" thick plate that I can pin in about 5 different locations to increase or decrease the size of the opening. I've been able to use it in conjunction with my convection plate to fine tune the temperatures across the entire length of the smoking chamber. I was skeptical at first, as I didn't request it, but as I've become familiar with it, I've been able to run temps from 500 - 225 all the way across.
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Re: Firebox Opening

Postby Jahbass » Thu Oct 06, 2016 12:14 pm

Newbie, first time poster . From Northern California (Humboldt)I'm starting a stick burner and I'm trying to get some information on a lot of things,but to start with the firebox.I have a 320 gallon propane tank on the trailer that I bought in Turlock California.40"x112".
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Re: Firebox Opening

Postby RWBTEX » Thu Oct 06, 2016 1:49 pm

Can you guys just speak in english so I can understand all that mathmatical stuff, lmao
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Re: Firebox Opening

Postby k.a.m. » Thu Oct 06, 2016 2:33 pm

RWBTEX wrote:Can you guys just speak in english so I can understand all that mathmatical stuff, lmao

Anything for you Arnie. :D :lol:
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Re: Firebox Opening

Postby Jahbass » Sun Oct 09, 2016 2:13 am

Ok, Maybe I shouldn't have said I was from California ,But I'm am and I could use some of that Texas barbecue knowledge .So let me try again .How big should my fire box be for a 320 gal Tank 112" long
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Re: Firebox Opening

Postby k.a.m. » Sun Oct 09, 2016 8:27 am

Jahbass wrote:Ok, Maybe I shouldn't have said I was from California ,But I'm am and I could use some of that Texas barbecue knowledge .So let me try again .How big should my fire box be for a 320 gal Tank 112" long

Well in all fairness you really did not ask how big a firebox you needed in your first post. :lol: You did say you needed help just not what kind. :D
First thing I would do is start a thread on your build separate from this one that way we can follow it.
Here is a link to the Pit calculator I plugged in your numbers to give you a start. If you need any help feel free to ask or message me.

All the best,

Kevin

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Re: Firebox Opening

Postby RWBTEX » Tue Oct 11, 2016 9:45 pm

k.a.m. wrote:
RWBTEX wrote:Can you guys just speak in english so I can understand all that mathmatical stuff, lmao

Anything for you Arnie. :D :lol:


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Re: Firebox Opening

Postby Jahbass » Thu Jan 12, 2017 6:52 pm

Here some pic. doors are 42Lx20H.Thinking about putting a Pig door on the other side.
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Re: Firebox Opening

Postby Unclebrick » Mon Jan 16, 2017 9:42 pm

Hello all, I hope I am doing this right as I am not a computer person. My question concerns the actual cut dimensions for my firebox to cook chamber. I have a 250 gallon tank with an old air compressor tank for the firebox. The firebox tank measures 43 x 24. The 43 length comes from cutting one end to accomodate flat plate for air intake. According to feldons calculations my fire box exceeds the min requirements by 101.1. My opening says 19.91 for a half moon opening so I rounded to 20 inches. My question is how do I lay out the measurements for my cuts. I am definitely not a math person so please keep it simple for this old marine. My other question concerns my smoke stack, I have a 4 inch square piece of conduit from an old light pole. How long should it be and how deep into the cook chamber should it be. Thank you to everyone in advance for your help.
Last edited by Unclebrick on Tue Jan 17, 2017 11:20 am, edited 1 time in total.
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Re: Firebox Opening

Postby k.a.m. » Tue Jan 17, 2017 9:29 am

Unclebrick wrote:Hello all, I hope I am doing this right as I am not a computer person. My question concerns the actual cut dimensions for my firebox to cook chamber. I have a 250 gallon tank with an old air compressor tank for the firebox. According to feldons calculations my fire box exceeds the min requirements by 101.1. My opening says 19.91 for a half moon opening so I rounded to 20 inches. My question is how do I lay out the measurements for my cuts. I am definitely not a math person so please keep it simple for this old marine. My other question concerns my smoke stack, I have a 4 inch square piece of conduit from an old light pole. How long should it be and how deep into the cook chamber should it be. Thank you to everyone in advance for your help.

What is the dimensions for your firebox?
Are you going to cut off domes and cap or are you trying to mate two dome ends?
Always remember slow and steady wins the race.

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Re: Firebox Opening

Postby Unclebrick » Tue Jan 17, 2017 11:23 am

I am keeping one end domed and the other will be cut off to allow for flat plate for air vents. The length is 43 inches x 24 inch dia. The 43 inch length was used in my calculations. I plan on meeting up the domed ends
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Re: Firebox Opening

Postby k.a.m. » Tue Jan 17, 2017 1:00 pm

Unclebrick wrote:I am keeping one end domed and the other will be cut off to allow for flat plate for air vents. The length is 43 inches x 24 inch dia. The 43 inch length was used in my calculations. I plan on meeting up the domed ends

On your 4" square exhaust. You need 972.61 Cu. in. of area. Each inch of your 4" exhaust represents 16 Cu. in. so you would need roughly 61" of exhaust for the 4" to work. I know for a fact that you will have problems with this scenario and recommend either a 6" ID round 34" tall or use two of your 4" and make them 30" tall.

On your firebox, there is no easy way to explain the cut to mate two domes. Basically you are cutting an elliptical opening into the cooking chamber to receive the firebox. If you would like to talk about it message me your number and I will try to explain a way to set up the cut.
Always remember slow and steady wins the race.

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Re: Firebox Opening

Postby Unclebrick » Tue Jan 17, 2017 6:39 pm

The pic is of my firebox. I am cutting the left side with the chalk mark as you are looking at the picture to put the flat plate for air vents. I may make it top loading unless I am better served by making the opening on the end flat with the air vents. Any thoughts on that would be greatly appreciated. By the way, K.A.R., I sent you a pm, but I am not sure I did it right or not
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Re: Firebox Opening

Postby k.a.m. » Tue Jan 17, 2017 8:18 pm

Message did not go through I sent you one. :D
Always remember slow and steady wins the race.

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