R.F First build adventure.

[Mike rainwater]

Ok, greetings everyone. Starting this first smoker project with a small free propane tank. Up front I'd like to express appreciation for any constructive input. The demensions are 14" outside diameter and 31 from weld seam to weld seam. So far I've got some hinges and therometers. The FB will be made from 1/4" plate. The box is a tad big for CC size according to the calculator as it is 14" cubed. Can I make adjustments for this along the build?

 

[weedeater]

Are you using this calculator for your build? https://www.smokingmeatforums.com/t...moker-how-to-calculate-build-tutorial.268692/

It will lead you in the right direction. A little big on the FB is not a problem and better than a tad small. Post pics of your tank and plans and you will get lots of good help here! Have fun. Will be watching.

Weedeater

 

[daveomak]

Bigger is better... Don't worry about the size of the FB.... As long as it is as big as minimum suggested, you are good to go..

 

[Mike rainwater]

Are you using this calculator for your build? https://www.smokingmeatforums.com/t...moker-how-to-calculate-build-tutorial.268692/

It will lead you in the right direction. A little big on the FB is not a problem and better than a tad small. Post pics of your tank and plans and you will get lots of good help here! Have fun. Will be watching.

Weedeater

Thanks. I plan to go by the calculator pretty close. I already had ordered the plate for the FB when I realized it was a bit big. To late to change before shearing. Seem the most difficult part of this build I'd figuring that CC/FB opening

 

[Mike rainwater]

Thanks. I plan to go by the calculator pretty close. I already had ordered the plate for the FB when I realized it was a bit big. To late to change before shearing. Seem the most difficult part of this build I'd figuring that CC/FB opening

Bigger is better... Don't worry about the size of the FB.... As long as it is as big as minimum suggested, you are good to go..

Hi Dave. Hoping the FB size was going to be ok. With a 14 outside tank diameter, 1/3 height for cutting the opening out of the end to mount the FB would be = 4.66 or 4.75 inches rounded off. This sound right?

 

[daveomak]

14D x 31L(34) = 13.75x13.75x0.7854x34 = 5,049 cu. in.
5049x0.004= 20 sq. in. ... The green area is what we will solve for.....


6.8" radius and for ED, segment height, 3" is the calculated height... BUT, due to the narrow CC and it's length, FRICTION will be a problem when it comes to air flow... I'm suggesting use 5" for ED to be sure to eliminate the friction loss in your smoker... That leaves 9" for cooking grate and food... it will work well...
Leave a 5" opening at the end of the RF plate...

Exhaust stack.... 5049x0.022= 111/0.7854x3x3 =16".. BUT.. again on that small a smoker, make the 3" ID stack 34-36" above the CC for good air flow... the 3" stack will reduce friction also... On a small smoker, friction is a big deal..

The FIRE BOX.....
5049x0.001= 5 sq. in. of opening 20/80 top to bottom... BUT... because of the size again, I would go with 8 sq. in.....
3" for the upper air inlets
5" for the lower air inlets..
something like below...
....

AND also a plenum for the exhaust stack to hook up to so the stack gets good air flow and doesn't screw up the cooking area...


Dave....

 

[Mike rainwater]

14D x 31L(34) = 13.75x13.75x0.7854x34 = 5,049 cu. in.
5049x0.004= 20 sq. in. ... The green area is what we will solve for.....
View attachment 366694

6.8" radius and for ED, segment height, 3" is the calculated height... BUT, due to the narrow CC and it's length, FRICTION will be a problem when it comes to air flow... I'm suggesting use 5" for ED to be sure to eliminate the friction loss in your smoker... That leaves 9" for cooking grate and food... it will work well...
Leave a 5" opening at the end of the RF plate...

Exhaust stack.... 5049x0.022= 111/0.7854x3x3 =16".. BUT.. again on that small a smoker, make the 3" ID stack 34-36" above the CC for good air flow... the 3" stack will reduce friction also... On a small smoker, friction is a big deal..

The FIRE BOX.....
5049x0.001= 5 sq. in. of opening 20/80 top to bottom... BUT... because of the size again, I would go with 8 sq. in.....
3" for the upper air inlets
5" for the lower air inlets..
something like below...
View attachment 366707 .... View attachment 366708

AND also a plenum for the exhaust stack to hook up to so the stack gets good air flow and doesn't screw up the cooking area...


Dave....

Greetings again, I Thank you greatly for the time it took to calculate this and the guidance. You're answered a bunch of questions with your kind response. Guess now I can have a better plan. Just gotta get busy fabricating. Thanks I'll try to load some pictures as I progress along. Was able to pick up some metal today.

 

[Mike rainwater]

14D x 31L(34) = 13.75x13.75x0.7854x34 = 5,049 cu. in.
5049x0.004= 20 sq. in. ... The green area is what we will solve for.....
View attachment 366694

6.8" radius and for ED, segment height, 3" is the calculated height... BUT, due to the narrow CC and it's length, FRICTION will be a problem when it comes to air flow... I'm suggesting use 5" for ED to be sure to eliminate the friction loss in your smoker... That leaves 9" for cooking grate and food... it will work well...
Leave a 5" opening at the end of the RF plate...

Exhaust stack.... 5049x0.022= 111/0.7854x3x3 =16".. BUT.. again on that small a smoker, make the 3" ID stack 34-36" above the CC for good air flow... the 3" stack will reduce friction also... On a small smoker, friction is a big deal..

The FIRE BOX.....
5049x0.001= 5 sq. in. of opening 20/80 top to bottom... BUT... because of the size again, I would go with 8 sq. in.....
3" for the upper air inlets
5" for the lower air inlets..
something like below...
View attachment 366707 .... View attachment 366708

AND also a plenum for the exhaust stack to hook up to so the stack gets good air flow and doesn't screw up the cooking area...


Dave....

 

[Mike rainwater]

Hi Dave,
This journey through building a smoker has been quite the challenge. Converting from wood working to metal reveals I don't have the necessary tools. From the 5049 CC size I changed the exhaust to a 4 inch pipe. What would be the recommended height. I have looked and looked for the calculator and it alludes me. I will load some pics of the build shortly. Thanks

 

[daveomak]

Exhaust Calculation..

ESV in cubic inches_____________________________ ... = Stack Length in inches (36" +/-)
0.7854 X Stack Diameter X Stack Diameter

Adjust the diameter of the stack, until the proper length is achieved... be sure to measure the actual internal diameter of the pipe used..
this is for round stacks only..

 

[Mike rainwater]

Thanks for your help. Here's what I came up with. Looking forward to trying it out.

 

[weedeater]

Mike that looks really good! Now let’s see some smoke coming out the stack and some pics of those first cooks.

Weedeater