OT - building my own upright smoker

busmania · March 2016

I have tried another forum but it is slow and I am not getting a response. Can someone tear my ideas apart? I made a reverse flow stick burner last year and am now looking to make another smoker as the one I made is small...plus I like building things.

When making an upright smoker, do I need to take the same measurement and draft considerations into account as I would if it was sitting sideways like a traditional stick burner? Doesn't the fact that it is upright kind of create a draft? For example, a weber smokey mountain (same idea here) doesn't have an exhaust stack to create draft. I guess my question is, do I need to calculate the size of the FB to CC opening or can I just cut a 8-10" circle in the firebox (FB to CC) and then a short 3-4" tall exaust that is about 4" wide (or even NO exhaust? I would have a baffle on top of the exaust to open/close as needed.

Here is my latest idea. Thoughts? Again, if a Weber Smokey mountain (and other uprights) don't have an exhaust stack, will this need one? Or does the rising heat automatically create the draft I need? Tear my design to pieces please!

And yes, my EGG is STILL my favorite...I just like building things.

HeavyG · March 2016

Cool! Look forward to seeing your project unfold.

Heat naturally rises so I don't see any real need for a stack to create a draft. I think a stack does make it a bit easier to mount a slide/plate to control flow if needed. As you said, the WSM and most of the UDS's I've seen do not have a stack for a top air vent.

What might look cool tho is to weld a short length of the appropriate diameter pipe on top of your dome and then put a shiny stainless Smokeware cap on it then not only does it look neat (shiny!) but it allows air flow control and rain protection (which really isn't a big deal for the most part but still...).

busmania · March 2016

HeavyG said:

What might look cool tho is to weld a short length of the appropriate diameter pipe on top of your dome and then put a shiny stainless Smokeware cap on it then not only does it look neat (shiny!) but it allows air flow control and rain protection (which really isn't a big deal for the most part but still...).

That is a great idea. In fact, I have one sitting in my shed collecting dust! I have the old version and didn't like the lack of fine tuning for super low n slows so I switched back to the daisy wheel. I think for aesthetic reasons, I will have at least a short exhaust stack and also to adjust the air flow like you mentioned. My wife is going to kill me when I break the news to her...."why do we need ANOTHER grill?" I already have 4...and recently gave away my weber smokey mountain (more on loan) to a friend in need.

WeberWho · March 2016

Keep us posted how it goes. This will be a good thread to follow. Thanks

SGH · March 2016

@busmania
Brother there are numerous things that come into play when designing the total through put and needed pull of draft. With that said, and without getting long winded here, final draft pull is reduced by half when the horizontal flow is circumvented or done away with. Thus, the calculations created by Feldon go out the window in a sense when building a vertical. They are still good for reference, but they are no longer a absolute.
Any design that has horizontal flow certainly depends on either a pulled draft, a induced draft, or a forced draft. This is not entirely the case for vertical flow. However, what a stack does bring to the table on a vertical is the through put is increased as is the speed of flow. Which up to a point is a great thing.
Next, with a certain amount of pull draft, you eliminate the rig from running positive pressure. You can force it to run either neutral or slightly negative pressure. What is the benefit of this? Have you ever opened a 600 degree BGE without burping it? The ensuing fireball is a result of running under positive pressure. Due to the size and shape of the BGE, at super high temps it's heat output exceeds its total draft through output. Thus it runs positive. I use the BGE analogy as a crude example. It's not a true apples to apples comparison, but it makes the point.
It's for the above reasons that most vertical builders use a simple rule of thumb to avoid positive pressure and forced down draft. Simply divide diameter by 4 and use the sum as length and width. But multiply length times 2.
Example- 24 inch chamber.
24/4=6 Diameter.
6x2=12 Length.
Thus, the diameter of your stack would be roughly 6 inches. The length would be 12 inches. Now you can use a smaller diameter if you wish, but you would need to then increase length to keep the same volume. And for clarity, the above is not a true design calculation. It's simply a rule of thumb that works and works well for true wood fired verticals.
Here are a couple of things to consider also. The WSM was used as a example. However the WSM is not fired by a true fire. It's simply smoldering charcoal or lump. This is why it works with no chimney. Same as the BGE. However if you are building a true wood burning vertical, I assure that in order to function properly that a good exhaust is needed.
One last thing. All of the above is based on the typical vertical design of firebox volume being equal to but no greater than 1/4 of chamber volume. If you increase firebox volume beyond 1/4 of the total chamber volume then you simply must recalculate. This is simple math, but should be done just the same. For clarity, I'm vaguely familiar with through put and final draft. If you would like to talk farther on the matter, feel free to give me a call this weekend. I will gladly help you crunch the numbers to determine final volume for running neutral or slightly negative pressure. Again and for clarity, all the above only applies to true wood fired, live fire units. Units that run on charcoal, lump, or a smoldering means, are not draft dependant (up to a point). However a rig running off of live fire is.

Edit- Above I did not touch on flow restriction due to racks, grates and loading. This was intentional as I was trying to stay brief. But know that they do figure into the equation.

Ozzie_Isaac · March 2016

@SGH drops mic and walks away .......

Jeepster47 · March 2016

Here's a great paint scheme ... food out of it was good!

Image: https://us.v-cdn.net/5017260/uploads/editor/8v/hjr54hifpezs.jpg

busmania · March 2016

Ozzie_Isaac said:

@SGH drops mic and walks away .......

Wow, yes, SGH that is amazing info. Thank you. I will indeed most likely take you up on your offer to go over a few things. I have followed your advice for some time on here and continue to appreciate it! I used Feldons calc on my reverse flow but know this will be different.

Also great point on smoldering versus an actual fire. Hadn't thought of it in that regard and I do indeed want an actual fire.

busmania · March 2016

What do you think of these numbers? I am basing this off of SGH guidelines but going off a little bit (I want a bigger firebox). SGH, would love to call and pick your brain. You can pm your number if that offer is still open. Been crazy around here with a 2 week old newborn! 60 gallon tank...this is what it is all being based on. (20" diameter, 48" tall) 18" x 18" x 20" tall fire box (13" diameter circle for firebox to cooking chamber cut out) 5" exhaust, but 12" tall instead of 10" to make up for the bigger fire box. Or should I go 14" tall? And I decided I am going to design it to look like an old school bomb. LIke the pictures below. http://www.dreamstime.com/royalty-free-stock-images-3d-render-bomb-falling-image15484549

busmania · March 2016

Sorry for the terrible formatting. Why does this site do that? I swear I had it in paragraph form.

theyolksonyou · March 2016

I know absolutely zero about building a smoker, but I am incredibly envious of you and people with your skill set.

HeavyG · March 2016

busmania said:

What do you think of these numbers? I am basing this off of SGH guidelines but going off a little bit (I want a bigger firebox). SGH, would love to call and pick your brain. You can pm your number if that offer is still open. Been crazy around here with a 2 week old newborn! 60 gallon tank...this is what it is all being based on. (20" diameter, 48" tall) 18" x 18" x 20" tall fire box (13" diameter circle for firebox to cooking chamber cut out) 5" exhaust, but 12" tall instead of 10" to make up for the bigger fire box. Or should I go 14" tall? And I decided I am going to design it to look like an old school bomb. LIke the pictures below. http://www.dreamstime.com/royalty-free-stock-images-3d-render-bomb-falling-image15484549

Here's an online tool that may be of help with some of your number crunching: http://www.feldoncentral.com/bbqcalculator.html

busmania · March 2016

theyolksonyou said:

I know absolutely zero about building a smoker, but I am incredibly envious of you and people with your skill set.

The only thing stopping you is your own fear of failure! I'm not a welder but I am a do it yourselfer but I tought myself to weld on my first smoker project.

HeavyG said:

busmania said:

What do you think of these numbers? I am basing this off of SGH guidelines but going off a little bit (I want a bigger firebox). SGH, would love to call and pick your brain. You can pm your number if that offer is still open. Been crazy around here with a 2 week old newborn! 60 gallon tank...this is what it is all being based on. (20" diameter, 48" tall) 18" x 18" x 20" tall fire box (13" diameter circle for firebox to cooking chamber cut out) 5" exhaust, but 12" tall instead of 10" to make up for the bigger fire box. Or should I go 14" tall? And I decided I am going to design it to look like an old school bomb. LIke the pictures below. http://www.dreamstime.com/royalty-free-stock-images-3d-render-bomb-falling-image15484549

Here's an online tool that may be of help with some of your number crunching: http://www.feldoncentral.com/bbqcalculator.html

I used Feldons for my reverse flow build but it is my understanding those numbers are for horizontal smokers. I want to build a vertical which naturally creates more of its own draft due to heat rising.

Ozzie_Isaac · March 2016

busmania said:

theyolksonyou said:

I know absolutely zero about building a smoker, but I am incredibly envious of you and people with your skill set.

The only thing stopping you is your own fear of failure!

Actually, there is a lot more than that stopping @theyolksonyou

theyolksonyou · March 2016

Creativity, intelligence and sobriety to name a few.

SGH · March 2016

@busmania
I will do you one better than that. I will post it here as well as PM it to you.
#228-627-5400.
Name is Scottie. I'm working some F"d up hours right now. But I'm home all day Saturday. If you need to speak before Saturday, call me at 3:00am CST. That is my lunch break.

busmania · March 2016

Thanks SGH. I'll plan on Saturday. My name is Matt. A HUGE thank you. I don't plan on building this beast for a few weeks as I have to aquire the parts and I'm researching plasma cutters right now.

SGH · March 2016

@busmania
I know it's just one man talking here, but I recommend getting one that will cut up to at least 3/8 thick metal. If you are remotely interested in fooling with metal projects, you will regret buying a less capable model down the road. I understand that money is always the deciding factor, but if you can swing it, here is a fine one. It will serve you well my friend.

http://m.lincolnelectric.com/en-us/equipment/pages/product.aspx?product=Products_PlasmaCutter-Tomahawk-375(LincolnElectric)&producttype=pc

busmania · March 2016

Yep, I'm between these two. I like that the miller can run on 120v or 220v. I don't really have 220v access but might in the future. The miller seems twice as powerful as the miller (40 amp vs 20). Cuts up to 3/8.

Lincoln
http://www.northerntool.com/shop/tools/product_200434920_200434920

Miller
http://www.weldingsuppliesfromioc.com/miller-spect...aQodAbwKWA

SGH · March 2016

@busmania
The Miller is a nice one too. But here is something to consider, if you run it off of 110v, the duty cycle suffers dramatically. Both are fine rigs though. But I'm partial to Lincoln.

busmania · March 2016

My mig is a Lincoln so I too am a big fan. What does duty cycle mean? I keep hearing that. Again though, if I buy 220v, I'll be running an extension cord from the kitchen where the fridge plugs in. That is my only 220v. I guess I could looI into converting an outlet in my garage but I'm already stretching the budget so prefer 120v for now.

SGH · March 2016

@busmania
Duty cycle is how long the unit will run at full capacity per hour.
Example- If you have a 50% duty cycle unit, you can only run it for 30 minutes per hour at full load.

busmania · March 2016

Makes sense. Thanks!

SGH · March 2016

@busmania
Don't know if you saw it, but on page 3 or 4 I posted a small pit that I'm building now.

busmania · March 2016

I did see it and am following! Here is the mini reverse flow I made.

http://www.smokingmeatforums.com/t/181548/my-first-build-help-me-please-reverse-flow

busmania · March 2016

Made a mock up to help me visualize and work out kinks before building. Roughly 40% of scale.

http://m.imgur.com/Hts4hD7

SmokeyPitt · March 2016

That looks like a really cool design. It looks like that smoker will be "da bomb".

I'll see myself out....

busmania · March 2016

SmokeyPitt said:

That looks like a really cool design. It looks like that smoker will be "da bomb".

I'll see myself out....

haha, I might try and sell one or two. Ill call the company "Bombs Away smokers and bbq." "Bombs Away BBQ" appears to already be taken by a cooking show. Here is the them I am thinking about going with. http://imgur.com/7Hnm20t

Thatgrimguy · March 2016

I would make sure it can handle a full aluminum steam pan.

You will need a way to handle the grease. That pit will hold a good amount of food and the grease can pool and burn and leave a oily sooty film on your food. You can look at the new Vertical Cabinet stick burners from Old Country at academy and get some ideas. That design has a few fans already.

I'd be a little concerned about the water pan. It's going to need to be DEEP or else I imagine it will empty quickly and cause temp spikes. I think the 2 deflectors will cover you. Make the deflector in the firebox extra thick. I would even think about taking the top deflector and making a V that channels to a drain outside so you can actively drain any excess grease. You can make it far enough away from the bottom grate than you can use an aluminum pan as your water pan when you wanted to do that. Personally I'd rather have the vaporizing flavor and excess grease draining out of the smoker. All in all it looks like a solid design.

YukonRon · March 2016

I swear these folks could tell you how to rewire a flux capacitor to enhance the Hadron Nuclear Particle Accelerator. I will stick to my BGE. Y'all are a dozen pay grades above my feeble mind resources.

busmania · March 2016

Thanks @Thatgrimguy, the grease is indeed an issue I have yet to figure out in my head. It definitely cannot be allowed to pool on the heat deflector plates cause it will burn/smoke. Thanks for pointing me in the direction of the old country bbq's. However, I am not seeing any wood fired vertical units in their inventory? Link perhaps?

OT - building my own upright smoker

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