Building an italian offset smoker

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Original poster
Jun 8, 2007

I'd like to build an italian offset smoker
I have a little propane tank to build the firebox and I need a large propane tank to build the smoke chamber

I have some questions to do:

1) Is it better to build an horizontal or a vetical smoker??
I'd like to use the water (water smoker) and I need to understand if it is possible with an horizontal smoker.

2) Does the heat reach the smoke chember from the firebox directly??

3) Is there a bulkhead to distribuite the heat homogeneously like in this photo??

Thanks to all

P.S. i can't speak english well, so my girlfriend translate my mail and your mail for me this is the reason of my delay
I'd like to build an italian offset smoker
I have a little propane tank to build the firebox and I need a large propane tank to build the smoke chamber

I have some questions to do:

1) Is it better to build an horizontal or a vetical smoker??
I'd like to use the water (water smoker) and I need to understand if it is possible with an horizontal smoker.

Anything is possible it is all about time and money. That being said it is easier and more common to have a vertical water smoker, I have found that other than the water assisting in maintaining the smoker temperature it does not seem to make a large difference (others may feel differently on that)

2) Does the heat reach the smoke chember from the firebox directly??
Not sure what you mean here but if you are asking is there a transition from the firebox to the chamber well if you design it that way yes if not no. The reason you would not do it directly would be to cool it down a bit for a cold smoker or for placement of the fire box

3) Is there a bulkhead to distribuite the heat homogeneously like in this photo??
Depends on the design. I like the design of the Lang smokers and they use a reverse flow design that does. If not you will have some hot spots but if you move the meat around that should not be an issue

P.S. i can't speak english well, so my girlfriend translate my mail and your mail for me this is the reason of my delay

No worries BBQ is a language all by itself
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Hi Ryoma!...Greetings from Georgia, USA!

It is so nice to have someone representing Italy to join us here at SMF!...Welcome!...

I will try to answers your questions as best as i am able. There are others here that can fill in any answers that I leave out in the event that I missed something..

Let's look at the questions now....

A-1) If built properly, water can be used in BOTH a horizontal and/or a vertical smoker.

A-2) Yes and no, dependent upon the way the smoker is constructed. I will explain more about this after question 3 since the answer to both questions are relative to each other.

A-3) The 'bulkhead' in the photo is actually a series of 'Tuning Plates'. These are used to 'tune' the heat distribution inside the cooking/smoking chamber.

Another, and quite different 'bulkhead' is illustrated and explained in Post #21 of this thread which deals with the Reverse Flow Horizontal Smoker-Cooker.

To help explain this as well as my answer to question 2, let's look at the the photo below which illustrates the Tuning Plates and the Baffle Plate.

I also created a graphic which will help you visualize those things which are not visible in the photo.

The Horizontal Smoker-Cooker w/ Offset Firebox

To help orient us to what we are seeing in the photo, keep in mind the following:

The firebox is located to the right and below the 'Baffle Plate' and is not visible in the photo.

The opening from the firebox into the cooking/smoking chamber is just beneath the Baffle Plate and is hidden
from view.

The heat/smoke exits the cooking/smoking chamber through the exhaust flue (smoke stack, chimney, etc.)
which is located at the end of the smoker opposite the firebox and would be just outside the left edge of the
photo and is not visible.

In the photo below you can see the Baffle Plate and the Tuning Plates (TP-1, TP-3 through TP-6) with
TP-2 hidden from view under the metal grid just to the right of TP-3, and TP-6 is only partially visible to the
left of TP-5.

Notice also the Baffle Plate tilts or slopes gently downward from the right towards the left as you can see from the shadow of the cooking grid above it.



Now I will try to explain how this all works.

As the heat/smoke flows into the cooking/smoking chamber, the downward sloping Baffle Plate directs the flow gently downwards and under the Tuning Plates as it flows from right to left towards the exhaust flue.

The Tuning Plates are adjustable and are positioned such that there is an open space between TP-1 and
TP-2. The width of the open spaces between TP-2 and TP-3, TP-3 and TP-4, TP-4 and TP-5, as well as
TP-5 and TP-6, are increased in width progressively as we proceed from right to left.

By making the spaces between the Tuning Plates wider, the amount of heat passing between the plates
will increase and make that area of the cooking/smoking chamber hotter.

By making the spaces between the Tuning Plates narrower, the amount of heat passing between
the plates will decrease and make that area of the cooking/smoking chamber cooler.

Through a trial and error process of adjusting the width of the spaces between the Tuning Plates, it is
possible to 'Tune' the cooking/smoking chamber to have an even temperature across the length of the
smoker from the firebox to the exhaust flue.

It must be noted however, that each individual smoker/cooker will have its own unique personality
and therefore will require its T.P.'s to be adjusted to its own individual characteristics...

Because of this, the adjustments outlined above are intended as a starting point only!...

For best performance the TP's should have a thickness of 1/4 to 1/2 inch (0.6 cm to 1.3 cm), with most
builders opting for a thickness range of 1/4 to 3/8 inch (0.6 cm to 0.9 cm), and should be made of iron
or steel in order to have the thermal mass necessary to moderate temperature fluctuations in the chamber.

Aluminum is not a suitable material for use in TP's since it lacks the thermal mass that is necessary.

Additionally, there is no set number of TP's to use in a smoker, nor is there a particular width of TP that must be used.

This is something you will have to decide based on the length of the chamber that you will be working with.

A greater length would require more TP's, a lesser length would require fewer TP's.

I created the graphics to reflect exactly what was shown in your photo, and this is the reason only 6 TP's are shown in them.


So...To complete my answer to to your second question:

Without the Baffle Plate and the Tuning Plates, Yes. The heat/smoke will enter directly into the cooking/smoking chamber, causing hot spots and cold spots.

In other words, the heat/smoke would begin almost immediately to rise towards the top of the cooking/smoking chamber where it would traverse the length of the chamber on its way to the exhaust flue.

Because of this, the end opposite the firebox would remain relatively cool at cooking grid level.

With the Baffle Plate and Tuning Plates, No. The heat/smoke will enter the cooking/smoking chamber indirectly, resulting in an even temperature throughout.

In this case, the Baffle plate, by sloping the heat/smoke downward, will in effect tuck the heat/smoke under the tuning plates, which will tend to act as a duct carrying the heat/smoke to the end opposite the firebox.

In the process of doing this, the tuning plates will be heated, which will then be able to release their stored heat under the cooking grid.

In addition, the heat/smoke which leaks upward through the progressively wider spaces (slots, gaps, etc.) between the tuning plates, will tend to surround any food items placed on the cooking grid, as well as even out the temperature from end to end in the chamber when adjusted properly.

Referring to your first question, a container of water may be placed on the Tuning Plates nearest the
firebox to produce steam to help regulate the temperature and to provide moisture in the cooking/smoking

A steam table pan, or tray, such as those used in a cafeteria or restaurant, works exceptionally
well for this task.

These pans and trays are made of food grade stainless steel, are rectangular in shape, and are available
in several sizes and depths, and they will withstand the heat in the event of boiling dry.

Here is a photo example of them:


Here are links to the websites of two different companies that build Horizontal Smoker Cookers w/ Offset Fireboxes...both are located in the state of Texas, in southern USA.

These websites have lots of photos that may be of help in planning the building of your smoker-cooker...sometimes a picture truly is worth a thousand words.

BBQ Pits by Klose located in Houston, Texas.

Gator Pit of Texas located in Houston, Texas.

The 'Pit Builders List' has links to many other Smoker-Cooker builders.


Next: The 'Reverse Flow Horizontal Smoker-Cooker'


I hope this has helped in some way...Good Luck in the building of your new Smoker-Cooker!...

Until Later...
Last edited:
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I read your answers, my girlfriend is translating the texts

When she will finish I'll answer to you

Thanks to all

Thanks!!... took me a while cuz I have to hunt 'n peck...never did learn to type...

If you think THAT's good....wait till you see the REST of the story!!!

I've been in the process of creating some graphics to go with the answers to the ??'s...

Until later...
Coley, your drawings and explainations have helped me understand how to properly tune my home made smoker better than anything I have run across in the 5 years since we built it! I can't wait to start re tuning it! It dumb founds me that I couldn't see your simple yet effective logic my self. Thanks much my friend! Terry
Coley you are very talented and have a very good sense of judgement. That is one awesome presentation. The pics you show have the smoke stack on the top of the smoker opposite the fire box. What if the smoke stack was cut in under the grate level?.
Thanks Guys!!...It's VERY humbling to receive all those wonderful compliments!!...

Now ya'll done went and got me blushing!...

Just trying to use the talents the Lord blessed me with to help others...Couldn't do it without His help!!!

I hope the post will be of help to all that read it.

First things first though...Hi there Terry!...Welcome aboard the SMF!...
Glad you joined our little family here!!

It's a Great place to be...Great Folks, Great Food, Tons of info...and More Fun than you can shake a stick of firewood at!...

If you haven't done it yet, then check out Jeff's Free 5 Day eCourse!...Lots of good stuff in there...Take it from Me!...

And Hey...You can't knock the price!...

Again...Welcome Aboard Terry!...I know you're gonna like it here...

Please let me know how you come out with the adjustments. But be will take some 'fiddlin' around with the TP's. Thanks.

- - - - - - - - - - - -

Hi there Marvin!,

I've read about bringing the stack down to, or even under grate level, in an attempt to lessen the temperature differential between the firebox end and the end opposite the firebox.

In reading about this I've learned that some swear by it, and others swear at the majority do the former rather than the latter.

When it comes down to trying it...IMHO it should be tried in a non-destructive and non-permanent least until it is determined whether or not the results are satisfactory.

With that said...Give her a whirl and see if it gets the results you desire.

It can probably be done with aluminum clothes dryer duct or hose...and if it works the way you want, then all you gotta do is make it permanent.

On the other hand...if it doesn't work as expected, there's really nothing lost except a little time and a couple bucks worth of dryer duct.

Be sure to keep me posted.

I am concerned about the possibility of over-doing it and making things a mite too warm toward the top of the chamber. It most likely won't be a problem though.

I created some graphics for you about some possible configurations for lowering the flue...

I'm not certain at this point if the flue would need to be lowered more or not. I feel that this is about the best compromise at this point for a smoker with two grates for balancing the temps between the top and bottom grates, without being too hot, or too cool on either, or both.

If there were only one grate in the lower position, I feel that it could be brought in at a lower position.

Please remember...This is only one mans humble opinion, and is NOT wrote in stone.

This needs to be tested thoroughly before considering making any changes to an existing smoker.

Hopefully...this may be food for thought on the subject and perhaps others here will have some better suggestions on this matter.

I hope this may have helped in some small way...

To you and to the others...Thanks again guys for the compliments!

EDIT: On further research it has come to my attention that, due to having received wrong information in the past, VOC's are not as much of a problem as first thought. Therefore, the section on VOC's has been removed so as not to be misleading to anyone on this subject. Thanks

Until later...
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i have read to leave the smoke stack wide open, controlling heat with the intake damper. my smoke stack has no damper. i have a rain shanty on top, that i do pull off sometimes. depends on the weather.
Coley -

If the VOC vent is below the top of the cook chamber won't it just recycle the VOCs back into the smoker? The general consenus is to put the stack in the side level with the grates to generate even air/smoke flow accross the grates.

In general I don't think the VOCs are a big concern but with a side firebox maybe you could add a high temperature vent filter on the instake. With a vertical it'd probably have to go between the wood box and the water pan. so you don't absorb the moisture.

Excelent illustrations kiddo!

Hi Coley

My girlfriend is just came back from the university and she translate your answer for me
Your exlpanations are excellent and hour graphics very helpful.

She needs to translate my answer for you

Sorry for the delay

Thanks to all
Hi Ryoma,

I'm glad to be of help to you!...
I have more work to do to on graphics and the text as this continues to be a work in progress.

As you have probably noticed, more info has been added to the post.

I'm working on it whenever I'm able to do so, but it is still going to take me a while to finish with it.

Hopefully, as work continues, it will be of even more help to you.

Before long you'll have that smoker built, seasoned, fired up, and smoking your first load of BBQ in it!

I'm getting excited about it already!!

Hungry too!!!

Until later...
Coley, that is the best explanation of smoker dynamics I have ever seen... great job! Thanks for sharing your talents and wisdom with us!
Thanks Guys!!...

I've still got some work to do before that post is finished...gonna be a lo-o-o-ong post before it's over with!!...

Like I said...'Stay Tuned!...Don't Touch That Dial'!...

May have to rewrite some of it to make a sticky or sumpthin'...

Glad all the hard work is helping folks!!...

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