First RF Smoker build

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I checked in on roll call and now I'm ready to rock, I have used vertical smokers in the past with good results but this will be my first horizontal rf smoker. I had a propane tank given to me a little while ago and I've checked out a lot of builds on this site and read a lot of posts. I'll post pictures and build updates as I go.

A couple of quick questions before I get started;

The tank I have is about 36" tall and 24" wide, how many gallons/pounds to you think the tank is?

Do propane tanks make good smokers, I've read that air compressor tanks make the best because of the thick wall? Should I not even worry about it?

 

[daveomak]

show, morning and welcome to the forum..... Propane tanks should have thicker walls than compressor tanks and make great smokers... 

Take lots of pics, (q-views), and keep us up to date on the build.... I'm in for the build.... 

...   Dave

 

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That's great to know, thanks for the information. I am currently on the look out for some scrap steel and parts so I can start making my firebox and legs for it. Its not going to be the biggest smoker, but I am sure it will be plenty big enough for family.

Quick questions whats the easiest way to measure the line for the door? Level it out and use a straight line to mark it?

Thanks

Heres a picture of the tank.
 

Photo0006.jpg

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• Oct 6, 2012

 

[daveomak]

The volume is about 65 gal....  It should have a label with the exact numbers...  

Before you cut the door, make sure it is squeaky clean inside... don't want any explosions...  also figure out the size firebox and where it is going.... and the RF plate and where it will sit... and the meat racks and where they will go... and the exhaust stack etc.... Draw it all out in chalk on the tank and ponder... Having to re do stuff is a pain ..... a big pain...  

In my signature line are some threads and formulas that will help.....   Dave

 

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Its a pretty old tank I haven't seen a plate or markings on it as of yet. Is there a specific place where the rf plate should sit, a few inches below the meat rack or above the bottom of the tank? 4", 6" is there a recommended size?

I've been to the calculator site so I have a good idea of firebox size and inlet size. Should the box be set into the tank a little bit? I've seen a lot of different styles on this site so far.

Thanks
 

 

[daveomak]

Its a pretty old tank I haven't seen a plate or markings on it as of yet. Is there a specific place where the rf plate should sit

If your firebox opening follows the contour of the tank and the top of the opening is horizontal, the RF plate should be about 2" above the opening to the fire box.... the reason being, there is friction loss on the walls and RF plate for the flow of heat and air... I recommend 1.5 times the firebox opening for the area under the RF plate and the same for the end of the RF plate..

, a few inches below the meat rack or above the bottom of the tank? 4", 6" is there a recommended size?

I've been to the calculator site so I have a good idea of firebox size and inlet size. Should the box be set into the tank a little bit?

I've seen a lot of different styles on this site so far.Generally about 1/3 the length of the firebox slid into the smoker... the top of the FB can align with the RF plate... Cut the opening in the firebox to match the bottom contour of the Cook Chamber .... 

Thanks
 

 

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smoker1.jpg

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• Oct 7, 2012

Pretty much cookie cutter this is just a sketch of the smoker I want to build, any ideas or thoughts are more than welcome. Not to scale obviously.

 

[daveomak]

Show, morning....  Looks like a great design....    2 things others have mentioned about their smokers....  1... having a drain for the cook chamber when hosing it out....   2...  On some fireboxes, folks put an air inlet above the fire... I think it allows more air flow through the smoker without adding air to the fire.... Haven't heard how that works....   When I built stoves for tents guys were using for hunting, I added an upper air inlet to the stoves for the sole purpose of allowing more air flow when burning wet wood.... I hated the creosote dripping in the tent when the stove was closed down to reduce the heat output after cooking.... It dripped on my wall-wall carpet I had in the tent.... The extra air intake worked great for that... moisture gone....    Dave

 

[ribwizzard]

Correct Dave,

The air inlet above the fire allows you to control airflow with less effect on the combustion process.( less effect on the heat of the fire)

The air inlet below the fire increases combustion and heat,

 

[daveomak]

RW..... maybe I got that from you....  I can't remember where I saw it on this forum....    Dave

 

[ribwizzard]

http://www.wedlinydomowe.com/smokehouse-plans/smokehouse-firebox

Dave, go here and check out firebox contruction, this is an awsome site if you have not found it yet.

 

[ribwizzard]

I actually built a firbox one time that preheated the secondary air and everthing like they show on here. It was a fun build but really was a little overboard.  I think as long as you have a raised stool with air control above and below the stool, thats all you really need for a small pit like everone on here builds.

Now if it was a comercial smoke house, that might make a big difference.

 

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Alright I added a drain for the main chamber and an upper vent to the firebox. Does it matter what the dimensions for the vent above the fire are? Should I carry the stack into the chamber and if so how far down should I go with it?

smoker1.jpg

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• Oct 8, 2012

 

[bruno994]

Show, typically on most RF designs, the RF plate is 4-5" below the bottom rack.  I put mine at 4" and I love the way mine cooks.  Your tank is the same diameter as mine, mine is just longer.  My bottom cut for my door was dead center, halfway down, so I placed my RF plate 4" below that which also allowed me plenty of space under the RF plate for the proper air flow and draft.  This will also give you enough room to add a second grate (upper) to increase your Q-pacity.  I have 5 1/2" between the 2 grates, which is plenty of room to fit briskets, shoulders, butts, pretty much everything except for turkeys.  When I do turkeys, I just pull the top rack out and then I have plenty of room.  If you can, make your grates slides (pull outs), you'll appreciate that especially with a 24" deep smoker.  Good luck on the build and feel free to ask plenty of questions and if you haven't yet, make sure and run your numbers on the pit calculator, big help there.

 

[show]

Show, typically on most RF designs, the RF plate is 4-5" below the bottom rack.  I put mine at 4" and I love the way mine cooks.  Your tank is the same diameter as mine, mine is just longer.  My bottom cut for my door was dead center, halfway down, so I placed my RF plate 4" below that which also allowed me plenty of space under the RF plate for the proper air flow and draft.  This will also give you enough room to add a second grate (upper) to increase your Q-pacity.  I have 5 1/2" between the 2 grates, which is plenty of room to fit briskets, shoulders, butts, pretty much everything except for turkeys.  When I do turkeys, I just pull the top rack out and then I have plenty of room.  If you can, make your grates slides (pull outs), you'll appreciate that especially with a 24" deep smoker.  Good luck on the build and feel free to ask plenty of questions and if you haven't yet, make sure and run your numbers on the pit calculator, big help there.

Thanks for that excellent information, that pit calculator is where I got the dimensions for the firebox and stack. Where did you make your cut on the top of the door? Is it at a 90 or do you have it at less of an angle?

Ive seen smokers with the stack on the top like the one I have drawn up or on the side. Is there one that would be better?

 

[ribwizzard]

One suggestion on the bottom cut of the door, just an inch up from dead center will keep the front edge of your cooker cleaner, keep the stuff  running down the inside of the door  on the inside instead of dripping down the outside of the bottom door seam.

Stack location is where you think it looks better, just extend it down into the cooking chamber to right above your top cooking rack.

 

[bruno994]

I did not go 90 degrees on my door, my door is 14" in total height. 

 

[daveomak]

Show, morning....  About the air inlet at the top of the firebox... It doesn't need to be large, just add some air flow, maybe 20% of the firebox inlet or so, and adjustable... add to it a thin wall tube extended part way into the firebox to direct the air toward the cook chamber... That way I figure the added air wouldn't add to the fire.....    

The smoke stack, I would extend down to about 4-5" above the lowest grate... help keeps the heat at the lowest level in the cook chamber and provide an air flow for faster cooking, like a convection oven, sort of....    Dave

 

[ribwizzard]

I usually set them up like this, pie vent under the fire grate and upper air vent just above the grate level. When starting my pit fire I will have both vents completely open, and the pit comes up to temp very fast, once I get it to tamp and I have nice coals going, i close the bottom pie vent completely and use the upper vent to control the smoker.

Now on really cold, windy, or rainy days, I will crack open the pie vent to give me the extra combustion I need to maintain the temp, or If I left it un-attended too long or the door was open too long, I will also use the pie vent (bottom vent) to recover my temp.

I recommend making both vents to the size that the pit calculator recommends. You can always close them.

 

[ribwizzard]

Here, you cant see the pie vent, but you can see grate placement and vent on the door. This firebox is working perfect.