SOB lookin for some help

[smokingohiobutcher]

So I am finally going to build my back yard patio smoker. I have always liked the design that real57vetteguy built and since i have virtually the same tank I am going to see if I can duplicate his success. http://www.smokingmeatforums.com/t/101769/reverse-flow-build-just-getting-started

Here is a crude drawing of my idea of what I want.  I have done the calcuations for a 100gallon tank, and will be making a 20" firebox.

1352375258499.jpg

• smokingohiobutcher
• Nov 8, 2012

Any help would be appreciated.

Thanks,

SOB

 

[daveomak]

Mark, morning....  Looks good.....  Are you planning on lowering the exhaust stack to somewhere inside the smoker ??  And consider a second air intake in the firebox, above the fire grate, for increasing air flow without increasing heat....  

With that type of design, the RF plate can be lowered significantly....  The distance under the RF plate can be 75% of the firebox opening...   That is because the firebox is split between two sides of the smoker and 1/2 of the flow is going in each direction....  The exhaust stack still needs to be calculated on the original calculations for the total smoker...

Dave

 

[smokingohiobutcher]

Evening Dave,

yes I am planning to put slide air intakes in the sides of the firebox above the fire grate for just that reason. Also, the stack will be all the way down to the grate level.

Thanks for the info about lowering the RF plate. That should make room for a higher 2nd shelf. I was wondering if I should use one damper in the top of the firebox

or 2 and a V shaped baffleplate welded to the bottom of the RF plate? The thinking that the V baffle would help direct the heat and smoke to the sides. 

SOB

 

[daveomak]

Mark, evening...   Are you planning on insetting the firebox into the tank or contouring the firebox to fit the circumference of the tank ???  

I'm thinking, contour the firebox to the tank.....   Cut a slot for the firebox opening.....  cut it on the curve portion of the tank.... Not long ways but short direction...  cut the opening what ever the calculator says the firebox opening should be.... when figuring the dimensions of the FB opening, make the length just shorter than the width of the RF plate..... That way, heat leaving the FB would be the width, more or less, of the RF plate and the entire plate would get heat...as the heat and smoke traveled toward both ends of the smoker....  

Hope all that makes sense... Never thought about a smoker built like this one before.... trying to think outside the box....

Center Firebox RF Smoker.jpg

• daveomak
• Nov 9, 2012

     

Center Fierbox RF Smoker.jpg

• daveomak
• Nov 9, 2012

click on pics to enlarge

With this configuration, you might install a plate, above the firebox, with a 1/16" gap under the RF plate to reduce the direct heat from the firebox on the RF plate....  Just trying to think ahead.....   Maybe suspend it from 1 center bolt to allow for expansion and contraction.... with the center of the RF plate higher than the rest, it should self support and leave a gap.... I would use at least a 1/2" bolt.... that point is going to get a lot of heat....  It could be reached from inside the firebox if need be... and use a think chunk of steel because of heat erosion on it.... it will be a b*tch to replace.....    

Dave

 

[ribwizzard]

Your right Dave, if the heat hits the reverse flow plate directly, its going to be smoking hot right in the middle. All the drippings will hit it and burn up causing a lot of burnt greese flavored smoke.

How about something like an upside down triangle below the reverse flow plate, right above the firebox.  Just a thought.  On my verticle smoker cabinets, I always had to channel the heat to the outer sides with series of plates.

 

[daveomak]

What are the pluses and minuses ???  Someone has built stuff that works and can add ideas here.....  If stuff here doesn't work, tell us that also.....    Mark needs some ideas that he can build on....    

Click to enlarge.... 

Center Firebox RF smoker 2.jpg

• daveomak
• Nov 9, 2012

 

[ribwizzard]

Honestly, I think the reverse flow plans that are on here are just about the perfect design for a back yard bbq.

Is there a reason for wanting the firebox in the middle?  Is it worth changing a near perfect design over?

 

[daveomak]

Personally, I think it is a great concept.... Smaller footprint for the back yard....  Uses fuel more efficiently.....   Granted there are bugs that may need to be worked out but that happens with every new idea.....   

Mark, GO FOR IT !!!  It will be a great learning experience and personal satisfaction will follow.... 

 

[ribwizzard]

It will use fuel more efficiently, no doubt.

Another ideal,.... dont attach the firebox directly to the cooking chamber, but plumb it in with a couple sections of 6" pipe. Leave a couple inches of gap between the two. I think that you would still have to build the firebox taller than you would for a side or reverse flow design due to the heat going straight up. At least thats what I found I had to do on the verticle smokers I built.

Another thing, these were very large verticle smokers, and I noticed when it was windy, it was hard to keep the chamber temp even. I solved that by installing mulitple exhaust vents. This build is a little different , it being a verticle smoker with a horizontal cooking chamber, but you might want to play around with the ideal of twin exhaust stacks. With cool air hitting one end of the tank, it will actually effect the airflow inside the tank and twin stacks would give you some control over that.

 

[jarjarchef]

I am very interested in this one. My first idea, before I looked around SMF more was very similar to this. I love the idea of the heat being centered and being more efficient use of fuel. My reason for not using it was mostly the fact it would cause issues on a trailer. Below are a couple of the ideas I was tossing around to compensate for hot spots.......

Water pan the directly over the fire box opening. Would make a very humid cook chamber. Sort of like a vertical water smoker.

What Dave had mentioned earlier the second metal plate, sort of like a heat sync for a CPU , directly over the fire box opening. I was even thinking running a series of bars from the plate to the outer edges of the RF plate to distribute the heat more like a heat sync theory.......

Using a baffle type system to regulate how much hot air was flowing into the cook chamber, with a metal plate over the openings as well.


Just my non expert thoughts. Hopefully they may inspire an idea. I would still like to use this style for a porch build....

 

[smokingohiobutcher]

Mark, evening...   Are you planning on insetting the firebox into the tank or contouring the firebox to fit the circumference of the tank ???  

I'm thinking, contour the firebox to the tank.....   Cut a slot for the firebox opening.....  cut it on the curve portion of the tank.... Not long ways but short direction...  cut the opening what ever the calculator says the firebox opening should be.... when figuring the dimensions of the FB opening, make the length just shorter than the width of the RF plate..... That way, heat leaving the FB would be the width, more or less, of the RF plate and the entire plate would get heat...as the heat and smoke traveled toward both ends of the smoker....  

Hope all that makes sense... Never thought about a smoker built like this one before.... trying to think outside the box....

I get the idea of the box being cut to fit the tank but was wondering if the heat that is hitting the curved part of the tank will be forced towarde thge outside of the  RF plate. If that makes sense?

Center Firebox RF Smoker.jpg

• daveomak
• Nov 9, 2012

     

Center Fierbox RF Smoker.jpg

• daveomak
• Nov 9, 2012

click on pics to enlarge

With this configuration, you might install a plate, above the firebox, with a 1/16" gap under the RF plate to reduce the direct heat from the firebox on the RF plate....  Just trying to think ahead.....   Maybe suspend it from 1 center bolt to allow for expansion and contraction.... with the center of the RF plate higher than the rest, it should self support and leave a gap.... I would use at least a 1/2" bolt.... that point is going to get a lot of heat....  It could be reached from inside the firebox if need be... and use a think chunk of steel because of heat erosion on it.... it will be a b*tch to replace.....

i do   like this idea! but wouldnt it be better to make the firebox with a top and cut a hole in it with a damnper to control which side gets more heat

View media item 178663
Dave

Honestly, I think the reverse flow plans that are on here are just about the perfect design for a back yard bbq.

Is there a reason for wanting the firebox in the middle?  Is it worth changing a near perfect design over?

Cause I want to!

It will use fuel more efficiently, no doubt.

Another ideal,.... dont attach the firebox directly to the cooking chamber, but plumb it in with a couple sections of 6" pipe. Leave a couple inches of gap between the two. I think that you would still have to build the firebox taller than you would for a side or reverse flow design due to the heat going straight up. At least thats what I found I had to do on the verticle smokers I built.

Another thing, these were very large verticle smokers, and I noticed when it was windy, it was hard to keep the chamber temp even. I solved that by installing mulitple exhaust vents. This build is a little different , it being a verticle smoker with a horizontal cooking chamber, but you might want to play around with the ideal of twin exhaust stacks. With cool air hitting one end of the tank, it will actually effect the airflow inside the tank and twin stacks would give you some control over that.

wouldnt having a damper to control the heat out of the firebox accomplish the same thing but with one stack?

FB damper2.png

• smokingohiobutcher
• Nov 13, 2012

Just spitballin! whatdo ya think?

SOB

 

[smokingohiobutcher]

Bump.

 

[jarjarchef]

Cause I want to!

wouldnt having a damper to control the heat out of the firebox accomplish the same thing but with one stack?

FB damper2.png

• smokingohiobutcher
• Nov 13, 2012

Just spitballin! whatdo ya think?

SOB

Again not a build expert, but do try to look at things logicly....

For heat control by direction of the smoke. I see some good and I see some grey..

Good: Love the idea of "tuning the cook chamber" by creating a hotter area in the RF plate and more air flow on that side.

Grey area and Spitball Ideas:

If your FR plate is one piece wouldn't it over a long cook almost even out in temp by contact. yes one side may be a little diffrent, but eventually the whole thing would be close in temp. So the radiant heat would be similar, the only diffrence would be the amount of air flow. Is there a way to split the plate so there is not muct contact for the heat to transfer with. Maybe with a drain channel runing front to back instead of left to right? Just a crazy curious thought....

I like the idea of the damper control for the air flow. Would you have more control if you were to actually put in two dampers. Maybe piviot in the center. This way you could actually close of the whole cook chamber if needed and possibly have more control of the air flow? It may also help buffer the direct heat of the firebox being directly below and not need the second buffer plate.

Very cool idea. I am very interested in seeing where this goes. I have an idea for a porch build and this would actually work very well for it.

 

[ribwizzard]

Just some more ideals for you, thats all...

Are you using a propane tank for cooking chamber?   If you skip putting a reverse flow plate inside the chamber, and used the bottom of the tank as the reverse flow plate ( run channel out both sides of the firebox to direct heat to both ends of the tank)  that would give you more room inside the tank ( in height ) to add more cooking racks. Your baffles you are wanting to use could be at the ends of the channel, right before heat enters the cooking chamber.   Just some ideals to through around in your head. Read my signature!!!

 

[smokingohiobutcher]

Again not a build expert, but do try to look at things logicly....

For heat control by direction of the smoke. I see some good and I see some grey..

Good: Love the idea of "tuning the cook chamber" by creating a hotter area in the RF plate and more air flow on that side.

Grey area and Spitball Ideas:

If your FR plate is one piece wouldn't it over a long cook almost even out in temp by contact. yes one side may be a little diffrent, but eventually the whole thing would be close in temp. So the radiant heat would be similar, the only diffrence would be the amount of air flow. Is there a way to split the plate so there is not muct contact for the heat to transfer with. Maybe with a drain channel runing front to back instead of left to right? Just a crazy curious thought....

I like the idea of the damper control for the air flow. Would you have more control if you were to actually put in two dampers. Maybe piviot in the center. This way you could actually close of the whole cook chamber if needed and possibly have more control of the air flow? It may also help buffer the direct heat of the firebox being directly below and not need the second buffer plate.

Very cool idea. I am very interested in seeing where this goes. I have an idea for a porch build and this would actually work very well for it.

I am hearing this from other builders i have asked too.

Here is a drawing of what i am thinking.

side view.png

• smokingohiobutcher
• Nov 15, 2012

damper closeup.png

• smokingohiobutcher
• Nov 15, 2012

Just some more ideals for you, thats all...

Are you using a propane tank for cooking chamber?    If you skip putting a reverse flow plate inside the chamber, and used the bottom of the tank as the reverse flow plate ( run channel out both sides of the firebox to direct heat to both ends of the tank)  that would give you more room inside the tank ( in height ) to add more cooking racks. Your baffles you are wanting to use could be at the ends of the channel, right before heat enters the cooking chamber.   Just some ideals to through around in your head. Read my signature!!!

No...its an old ai rcompressor...100gal...not sure on the thickness of the metal. it looks identical to the one real57vetteguy used for his.

Interesting...

SOB

 

[jarjarchef]

Looks good.... the only thing I would be curious about is the straight piece going straight down into the firebox.... is it needed or is there a purpose for it?

Again I am just throwing my thoughts out there. Ribwizzard and Dave have more skill and experience in their pinky than I do in my entire being. I am very intrigued by this build due to having one very similar in mind for a later date.

Jeramy

 

[smokingohiobutcher]

That piece is the adjustable damper that will swing left or right to allow more or less smoke and heat to flow to one side or the other of the smoke chamber. I am not sure it is needed...but at this point im not sure it would hurt if I was to put it in there. could always leave it open.

SOB

 

[ribwizzard]

What did you end up deciding on this?