RF air tank build

[Johnscrub]

This is my first time trying a reverse flow build. I have acquired an 80 gallon and a 25 gallon air tank. There dimensions are 20 x80 and 14x34.i am looking to use the smaller tank as a firebox. I know it will be slightly undersized. I'm looking for help on dimensions for cutting doors and other holes. I've used the calculator.. This is link to what I've got from it.. If anybody has time to look over it and give me some pointers it would be greatly appreciated.Link to BBQ Pit Calculator
Pics of what I'm working with..
Thanks

 

[JLeonard]

daveomak is the resident guru. Maybe he can help ya out.
Jim

 

[Johnscrub]

daveomak is the resident guru. Maybe he can help ya out.
Jim

Thanks
Yes I'm long time lurker.. I'm hoping so.

 

[LanceR]

Good morning, John

There's a much better calculator than Feldon's right at the top of this forum. As a general rule the firebox wants to be at least 1/3 the volume of the cook chamber and long skinny tanks like yours do better with a bit more than that as the calculator here shows.

I'm not an expert at smoker design so take this with a grain of salt until Dave O or someone else with more experience comes along.

Given a nominal volume of 18,480 cubic inches I suspect your smoker really wants a firebox around 7,000 cubic inches and your smaller tank, at 5,800 cubic inches ,is small enough that I don't think it is going to be satisfactory, especially in rainy, cold or windy conditions when you need more heat than usual.

If you have access to 1/4" steel and the budget for it a 20" cube shaped firebox would give you 8,000 cubic inches and have enough reserve volume to be sure to handle anything you want to cook. As a bonus it will be a lot easier to fit too.

What are you welding it with?

Best regards,

 

[Johnscrub]

Good morning, John

There's a much better calculator than Feldon's right at the top of this forum. As a general rule the firebox wants to be at least 1/3 the volume of the cook chamber and long skinny tanks like yours do better with a bit more than that as the calculator here shows.

I'm not an expert at smoker design so take this with a grain of salt until Dave O or someone else with more experience comes along.

Given a nominal volume of 18,480 cubic inches I suspect your smoker really wants a firebox around 7,000 cubic inches and your smaller tank, at 5,800 cubic inches ,is small enough that I don't think it is going to be satisfactory, especially in rainy, cold or windy conditions when you need more heat than usual.

If you have access to 1/4" steel and the budget for it a 20" cube shaped firebox would give you 8,000 cubic inches and have enough reserve volume to be sure to handle anything you want to cook. As a bonus it will be a lot easier to fit too.

What are you welding it with?

Best regards,

Good morning, John

There's a much better calculator than Feldon's right at the top of this forum. As a general rule the firebox wants to be at least 1/3 the volume of the cook chamber and long skinny tanks like yours do better with a bit more than that as the calculator here shows.

I'm not an expert at smoker design so take this with a grain of salt until Dave O or someone else with more experience comes along.

Given a nominal volume of 18,480 cubic inches I suspect your smoker really wants a firebox around 7,000 cubic inches and your smaller tank, at 5,800 cubic inches ,is small enough that I don't think it is going to be satisfactory, especially in rainy, cold or windy conditions when you need more heat than usual.

If you have access to 1/4" steel and the budget for it a 20" cube shaped firebox would give you 8,000 cubic inches and have enough reserve volume to be sure to handle anything you want to cook. As a bonus it will be a lot easier to fit too.

What are you welding it with?

Best regards,

Yes I saw that but was all Greek to me. I used Feldons as it was automatic.. It was lazy way I did it. I work in hydraulic so so have access to any type welder.. More than likely mig or Tig. I'm cheap so am going with free parts. Budget is tight ..I have a UDS that works great that I built and to be honest don't really know how much this will get used.. It is either make this or stand it up and make a smoker that way.

 

[radioguy]

John,
Welcome to SMF search is your friend. I built one similar to yours...52 gallon air tank. The tank is almost 100 years old.

I moved to to a trailer set up and just plobbed it down on the trailer...had a competion cook that year. I still would like to lower the tank by 6-8 inches and finish out the grate work. It cooks really well.

RG

First Build Patio RF 50 gallon "Lefty" version

Well, I've done enough reading and research, time to make some sparks! Since this is custom why not make a left-hand version. Really looking forward to some smoked meats this summer!!! 52 gallon compressor tank dated 1927, flat rolled steel, welded rolled ends, stout and heavy. using...

www.smokingmeatforums.com

Lefty gets new shoes....trailer

I've been cooking on "Lefty" for a while. Learned fire and heat control and have made many a meal on this cooker. I'm no Engineer just a do it myself type of guy. I sized the axle too small (.75") and it is starting to bend a bit. This cooker is heavy, not too bad if I keep it on the...

www.smokingmeatforums.com

 

[Johnscrub]

John,
Welcome to SMF search is your friend. I built one similar to yours...52 gallon air tank. The tank is almost 100 years old.

I moved to to a trailer set up and just plobbed it down on the trailer...had a competion cook that year. I still would like to lower the tank by 6-8 inches and finish out the grate work. It cooks really well.

RG

First Build Patio RF 50 gallon "Lefty" version

Well, I've done enough reading and research, time to make some sparks! Since this is custom why not make a left-hand version. Really looking forward to some smoked meats this summer!!! 52 gallon compressor tank dated 1927, flat rolled steel, welded rolled ends, stout and heavy. using...

www.smokingmeatforums.com

Lefty gets new shoes....trailer

I've been cooking on "Lefty" for a while. Learned fire and heat control and have made many a meal on this cooker. I'm no Engineer just a do it myself type of guy. I sized the axle too small (.75") and it is starting to bend a bit. This cooker is heavy, not too bad if I keep it on the...

www.smokingmeatforums.com

Thank you yes search is your friend. Nice build.. How did you determine your door cuts? Height mainly..I did search but nothing with a round firebox or cylinder one. Yes the main tank was made in 1976.. Little one no idea..

 

[radioguy]

Thank you yes search is your friend. Nice build.. How did you determine your door cuts? Height mainly..I did search but nothing with a round firebox or cylinder one. Yes the main tank was made in 1976.. Little one no idea..

I did my door cuts at 9 and 11 o'clock. It's up to you. It depends on your tank size. I put my shelf slide in a 1/4 " above the opening. I didn't need anything more on the top. My tank has a welded seam, I put that on top.

About using round FB you will end up with a football shaped opening. It takes a little extra math to figure the size. Just treat it like 2 times a normal circular chord.

RG