Reverse smoker. Pipe vs Steel Plate

[Tough old man]

I'm in the process of building a smoker. 72" x 22". During the build i have decided on a reverse flow. Problem is It has 2 doors with shelve frames already welded in. Be very hard to weld in a plate in the bottom now without doing it in sections.

So i came up with an idea and need your thoughts on it whether it would work or not. I'm planning on running a 6" id steel pipe from the firebox to about 6" from the end of the cooking chamber. Also I would have to buy the plate and I already having the steel pipe.


Question is whether this would work or not.

 

[luke duke]

I would weld the plate in pieces. Or scrap the reverse flow idea and use tuning plates.

 

[dwfisk]

I've seen 6"-8" pipe with holes torched in it successfully used to distribute heat/smoke in a traditional offset and see no reason why it would not work in a reverse flow. I built mine with tuning plates sitting on 1" angle tacked to the inside wall. Here is a link showing & explaining mine:
http://www.bbq-brethren.com/forum/showpost.php?p=2360399&postcount=21
Buttburner posted a better picture, same basic idea.
http://www.bbq-brethren.com/forum/showpost.php?p=2384319&postcount=4
I think you could adapt this concept into 2-3 1/4" plates you could work in around the existing fabrication and weld in place or just let gravity do its thing. IMHO reverse flow, however you get there is the way to go.

If you already have pipe its probably worth a shot, but I'm a little concerned about getting enough flow with one 6" pipe, can you fit 2?

 

[samfsu]

Hey Dave what is the silver equipment to the left of the smoker on your trailer? Another smoker?

 

[HUCKS]

i cooked beside a guy that had one built like that.it looked to be 6-7 inch pipe and he had no problems with it

 

[dwfisk]

Hey Dave what is the silver equipment to the left of the smoker on your trailer? Another smoker?

Yea, its a 24" square SS gasser w/ceramic fabric insulation and 4 racks. Members Mark from Sams Club via China for about $400. Got it about 10-12 years ago and cooked a bunch of Q, but nothing as good as you get with wood. I put it on the trailer to use as an oven and warmer, but in a pinch it will smoke too.

 

[Triple T BBQ]

I'm in the process of building a smoker. 72" x 22". During the build i have decided on a reverse flow. Problem is It has 2 doors with shelve frames already welded in. Be very hard to weld in a plate in the bottom now without doing it in sections.

So i came up with an idea and need your thoughts on it whether it would work or not. I'm planning on running a 6" id steel pipe from the firebox to about 6" from the end of the cooking chamber. Also I would have to buy the plate and I already having the steel pipe.


Question is whether this would work or not.

I would get the grinder out and pull the shelves out temporarily. Love the reverse flow plate in mine. Cooks super even with a nice hot spot right over where the firebox is inside the tank. Great for Chrisping up the chicken.:icon_smile_tongue:

 

[RevZiLLa]

I would get the grinder out and pull the shelves out temporarily. Love the reverse flow plate in mine. Cooks super even with a nice hot spot right over where the firebox is inside the tank. Great for Chrisping up the chicken.:icon_smile_tongue:

Sounds like the easiest and most quality way to go

 

[TuscaloosaQ]

Without the baffel plate being in, I think you will miss the radiant heat you get off of the baffle plate itself which is a big part of the reverse flow process.

 

[dkryzer]

Several years ago I faced this same exact issue and considered the pipe trick. I ended up welding in a baffle plate in pieces for this simple fact I wanted to make sure I had radiant heat. This ended up being a good decision. The pit performed great. I chalked it up as a lesson leaned and now build my pits the right way.

 

[Tough old man]

Crap I'd hate to have to grind them shelve frames out of there.

 

[Tough old man]

I've seen 6"-8" pipe with holes torched in it successfully used to distribute heat/smoke in a traditional offset and see no reason why it would not work in a reverse flow. I built mine with tuning plates sitting on 1" angle tacked to the inside wall. Here is a link showing & explaining mine:
http://www.bbq-brethren.com/forum/showpost.php?p=2360399&postcount=21
Buttburner posted a better picture, same basic idea.
http://www.bbq-brethren.com/forum/showpost.php?p=2384319&postcount=4
I think you could adapt this concept into 2-3 1/4" plates you could work in around the existing fabrication and weld in place or just let gravity do its thing. IMHO reverse flow, however you get there is the way to go.

If you already have pipe its probably worth a shot, but I'm a little concerned about getting enough flow with one 6" pipe, can you fit 2?

I looked at your pics. nice set up. Did you end up welding those plates together?

I could put in 2 6" pipes and drill holes in them all the way down starting with smaller holes going up if you think that would work. I know they wouldn't give off as much heat but will it be enough to do the trick.

I live in Baja, Mexico and everything you purchase is in full lengths meaning I would have to buy a 4' x 8' sheet of plating. LOL, I'm 70 yrs old 6' 255 lb weightlifter and stronger then a team of goats, but a 4 x 8 x 1/4" is not going to be the lightest to move around by yourself.....

 

[dwfisk]

Thanks, it works great. I have found no need to weld them together. The sheared edges fit together tightly and by the time I got a couple cooks of dripping goodness, they sealed right up. When I want to separate them now, it takes a little screw driver action.

Drilling holes in the pipe would seem to defeat the reverse flow mod; when I've seen pipe with holes it was for a traditional offset stickburner in lieu of tuning plates, not reverse flow.

 

[Tough old man]

Thanks, it works great. I have found no need to weld them together. The sheared edges fit together tightly and by the time I got a couple cooks of dripping goodness, they sealed right up. When I want to separate them now, it takes a little screw driver action.

Screw driver action.....LOL is that Vodka and OJ?

Ok let say i buy a sheet of plate steel. Would 3/16" work or does it need to be 1/4"?. Also how far from the end should i stop the plate steel. Again the smoker is 22" x 72".


Thanks for all coming to my rescue.

PT

 

[dwfisk]

IMO 3/16 will work fine. I stopped my plates about a foot from the end just cause it looked OK. Maybe TuscaloosaQ if following the thread and can weigh in, certainly more of an expert builder than me.

 

[TuscaloosaQ]

Standard baffel plate material is usually 1/4"material But... 3/16 will work fine it is defiently not going to burn out on a reverse flow. 1/4" radiates heat a little more. As far as the gap it needs to be at least equal to the square inches of the cutout going into the cook chamber from firebox to keep from interrupting flow in my opinion!!!

 

[Zin]

Just make sure you have more exhaust than intake and you will be fine.

 

[Tough old man]

Just make sure you have more exhaust than intake and you will be fine.

Are you talking if I use 1 or 2 -- 6" pipes?

 

[dwfisk]

I might be over thinkin this, so feel free to ignore me. What's the old saying "be careful of free advice, you only get what you pay for". Anyhow, I needed a brain teaser this afternoon and I am truly sympathetic to using what you have on hand to work with.
Here goes:

I have about 50 square inches of connection to my firebox. I didn't do any profound preplanning or calcs, that's just what I wound up with. My math says two 6 inch pipes would give you 56.5 square inches of connection (you know pie-r-squared).

My tuning plate is 17.5 inches X (up to) 60 inches or 1050 square inches providing radiant heat (the way I did mine I can do less but not more). Two 6 inch pipes, assuming you only take credit for the top half of each pipe gives you 1140 square inches for a 60 inch length (circumference = pie X diameter X 1/2 cause I'm only taking credit for the top 1/2 of the pipe X 2 cause you have 2 pipes).

My smoker works for me, I get good even heat distribution, helped a lot by the radiant heat and I can cook anywhere from 200*-375*. Given the similarity of the numbers, I think two 6 inch pipes, something like 48 to 60 inches should be pretty equivalent. In your situation, I would try the pipes.

To Zin's point, I think he's talking about getting the right exhaust and intake balance. Let's assume you want to use some of the same 6 inch pipe for your exhaust, you will have about 28 square inches of exhaust. Some of us believe in controlling the fire at the intake, so you only need up to 28 square inches of intake to be able to get a clean burn and control nasty smoke. Zin can correct me if I've missed his point.

OK, now my head hurts:wacko:. I'm gonna make a wild turkey rocks & feed the cows while everyone else double checks my math and offers alternative suggestions. GOOD LUCK!:thumb:

 

[Tough old man]

I'm not going to run pipe all the way down. Just a big inlet. So now for a reverse smoker i need a plate (baffle) Well I ran into another problem. For a plate here in Mexico (Steel plate) they only come in 4' x 10' sheets. Way to heavy to handle. What do some of you think about using CERAMIC TILE. Tile is cheap down here and can be replace when needed. 18" x 18" x 3/8" $1.01 ea.......Will they work?.........I have a commercial tile cutter, so no problem cutting them to size needed.