Smoker build

[tandito]

Hey y'all, new to the forum and just hoping to get some insight on If I have waisted my time on this build or might be able to salvage it. Tried to build a vertical offset smoker, pellet box comes in the bottom hits a baffle plate and essentially goes up channels on the sides. Under baffle where the pellet pot is will be around 400F, but the racks never go over 150F. Thinking about drilling some holes in baffle to help air escape the bottom "chamber". The baffles that go up the side are roughly twice the area of the pot opening if that makes sense.
* I also have no door seal so any recommendations would be helpful as well

3/16 steel baffle s up the sides

 

[millerbuilds]

Welcome to SMF from North Texas!
Air in and air/smoke out. The baffles are a starting point, along with how you have the exhaust connected, you may be losing all of your heat directly out of the stack. Tough to tell without watching it operate.

- Jason

 

[SmokinEdge]

Need better pictures of the inlet of the plenum in relation to the baffle and deflector plate. It looks like the plenum is not large enough height wise it looks to constricted flow of the exhaust.

 

[Winterrider]

Certainly an interesting looking rig

 

[tandito]

*hope this diagram helps some i can try taking more pics this weekend in the light of day.
*In theory the outlets are bigger than the inlet, but i think i need to increase the flow down low up the sides drastically
*the reason for the fire pot beeing off center and having an angles plenum is because the pellet box was hitting the tank. thinking about opening the plenum up a whole lot

 

[JckDanls 07]

So are you thinking reverse flow here ?? Looking at your pics that's what i'm gathering...

 

[tandito]

So are you thinking reverse flow here ?? Looking at your pics that's what i'm gathering...

Correct, that was the goal. I didn't know if it was possible and did zero research on if a vertical offset smoker Is possible

 

[JckDanls 07]

the plenum is not large enough height wise it looks to constricted flow of the exhaust.

I'm gonna have to agree with this.. Looking at the plenum in the pic... size wise it looks to be somwhere around an inch/inch in a half tall... maybe 4 inches wide... This needs to be much bigger.. .

 

[JckDanls 07]

Upon further review ..

So you have an interior wall creating a chamber up the sides all the way around ?? What is the gap in this chamber around the sides ?? How far from the top do the chamber walls stop (gap
at the top) where the heat and smoke dump back into the cook chamber ??

 

[SmokinEdge]

View attachment 713931
*hope this diagram helps some i can try taking more pics this weekend in the light of day.
*In theory the outlets are bigger than the inlet, but i think i need to increase the flow down low up the sides drastically
*the reason for the fire pot beeing off center and having an angles plenum is because the pellet box was hitting the tank. thinking about opening the plenum up a whole lot

The plenum of the exhaust is specifically what I was talking about. The piece the vertical exhaust stack is welded to is to small volume wise as a collector. You can only intake what you can exhaust. So restricting either end kills flow and heat transfer.

 

[tandito]

The plenum of the exhaust is specifically what I was talking about. The piece the vertical exhaust stack is welded to is to small volume wise as a collector. You can only intake what you can exhaust. So restricting either end kills flow and heat transfer.

that is [rectangular tubing at 2.5''*8"=an area of 20in^2] with a [4'' exhaust attached=an area of12.5in^2]
I hope i understand you, and i dont know what the rough dimensions should be for this but the exhaust plenum is bigger than the exhaust its self so i thought that would be sufficient?

 

[tandito]

Upon further review ..

So you have an interior wall creating a chamber up the sides all the way around ?? What is the gap in this chamber around the sides ?? How far from the top do the chamber walls stop (gap
at the top) where the heat and smoke dump back into the cook chamber ??

these openings are about10"wide with a peak gap of 1.5"= roughly 30in^2 on either side.
i deffinitly had my concerns with this and wouldve liked to get more area coming up the sides
it also stops a few inches below the top of door

 

[texomakid]

I love projects! Watching this one. Bookmarked.

 

[BigW.]

I appreciate your skills and creativity. Certainly a cool idea, hope you can get it figured out. Even with the pellet fan, I don't know if you can get the smoke from the top of the chamber, pushed back out the side. Maybe if you had another fan on the stack? I assume most vertical smokers have exhaust out the top for that reason.

 

[tandito]

I appreciate your skills and creativity. Certainly a cool idea, hope you can get it figured out. Even with the pellet fan, I don't know if you can get the smoke from the top of the chamber, pushed back out the side. Maybe if you had another fan on the stack? I assume most vertical smokers have exhaust out the top for that reason.

Thanks!
Interesting idea, That's seems very reasonable to do. I have try to do some research on these types of smokers and haven't run into much info on them.

 

[realdocBBQ]

I'm trying to figure out... well, the point, really. Why bring in the air, heat and smoke under a baffle, then direct it up along the sides only to come back down again and then... exhaust out the bottom? IN horizontal reverse flow, the baffle absorbs heat and distributes it more evenly (hopefully) across the cook chamber, leading to radiant cooking from below with NO smoke contact with the meat. Then the air redirects off the far end and brings the smoke back around to bathe the meat.

In your design, if I'm seeing it correctly, you have a baffle that absorbs the heat (400+F), then directs flow up along the sides - so those side baffles further absorb more heat - and brings the smoke up to the top, where it will then theoretically redirect back downward to bathe the meat and escape out the low-mounted exhaust?

From what I can see, while the exhaust pipe looks decent size, the miniature collector looking thing where it gathers the smoke from the cook chamber looks pretty small, and especially very short (in height, vertically speaking).? That looks like a 1x3 or 1x4 opening from the bottom of the cook chamber to the exhaust.

So, if I'm interpreting this correctly, I see a couple of areas I would change to get both better airflow AND better temps. But I don't want to go criticizing or correcting things if I've got the concept incorrect.

Let me know if I'm seeing this right and I can offer some more thoughts.

 

[SmokinEdge]

Hey y'all, new to the forum and just hoping to get some insight on If I have waisted my time on this build or might be able to salvage it. Tried to build a vertical offset smoker, pellet box comes in the bottom hits a baffle plate and essentially goes up channels on the sides. Under baffle where the pellet pot is will be around 400F, but the racks never go over 150F. Thinking about drilling some holes in baffle to help air escape the bottom "chamber". The baffles that go up the side are roughly twice the area of the pot opening if that makes sense.
* I also have no door seal so any recommendations would be helpful as well

View attachment 713898View attachment 713899View attachment 713902
3/16 steel baffle s up the sides

I have a video that shows a good exhaust plenum. Don’t mind the video necessarily but remember your cooker is essentially the same but vertical, this make reverse flow a little more challenging as hot air close to the exhaust which is directly above the heat source making it potentially hotter, is less dense than cold air. So to move that hot air you need a much larger exit than if the exhaust was at the top of the vertical cooker. You need a robust exhaust collector, or plenum. Watch the first couple minutes of this vid in my link, and look at the size of the plenum.

 

[JckDanls 07]

View attachment 713952
these openings are about10"wide with a peak gap of 1.5"= roughly 30in^2 on either side.
i deffinitly had my concerns with this and wouldve liked to get more area coming up the sides
it also stops a few inches below the top of door

Let me see if I have this right..

So the baffle plate is connected to the sides all the way around and then 2 places cut out on ether side with the vertical plates welded in ? Essentially all that heat in the bottom only has 2 small channels/passageways up the sides ?

 

[SmokinEdge]

Let me see if I have this right..

So the baffle plate is connected to the sides all the way around and then 2 places cut out on ether side with the vertical plates welded in ? Essentially all that heat in the bottom only has 2 small channels/passageways up the sides ?

That’s the way I see it. And I think he also needs more of those plates bringing heat up. Currently he only has 2 plates either side. In my opinion they need to be all the way around the inside of the smoker minus the door. Increase up flow and increase exhaust flow.

 

[JckDanls 07]

That's where I was going next...

The ideal thing would be to have a "sleeve" that is 3" (minimum) smaller diameter than the chamber... 3" will give you a 1 1/2" gap all the way around the chamber... Weld a solid plate on the bottom... Cut to height needed to be a few inches from the top...
Cut out the door opening on the inner liner and fill in the gap between the outer and inner walls...
Your exhaust (correct sizing) should pull from the inside chamber only... Down at the bottom of the chamber...

Just a quick overview ...