Wood burning stove style reverse flow smoker.

[SouthamptonSmoker]

forgot the pics of the latch, insulation and temp probe

[Big T]

[SouthamptonSmoker]

Is there any restriction on flue size diameter. I have selected a 71mm ID tube. This gives me quite a long flue, similar on height to my current bbq. As this will also stay, I was keen to have similar heights for the flue.

Is 71mm too small?

[Rodcrafter]

Less than 3” exhaust does cause a restriction, but this design is more of a vertical. But since the CC is so far from the FB you probably would need a good draft to help pull the heat in. I would use at least a 4” x18” pipe.


Making memories!

[SouthamptonSmoker]

Understood. The calculator suggested at that dims I should have about ~22" at that size. What if I took it to 40" so it was still the same height? Would that be an issue?

I was hoping it was reverse flow. My considerations where that my throat continues vertically to my firebox, as the geometry is what is should be, but just a section of my throat is vertical. The riser is fully insulated on all sides with 1" vermiculite. The riser is 500mm long. So the smoke travels a further ~50% of throat. Shall I add the area of the riser throat to the cooker chamber area and put it back into the calculator? So the riser is part of the cook chamber? This would only be an additional 43" square - so i didnt do this before as I thought it was insignificant compared to the 8568" it is already.

Of course I am green, never built one before and probably interpreting things to suit me lol. I really want it to work like a dream first time though lol.

I might put a temp gauge on the riser too, just to what is going on in that section.

What are the fundamental difference between vertical and reverse flow. With reverse flow, we must have this draft created? Whereas vertical i guess just drafts with the convectional heat?

I guess my current one is a very small vertical. I use a large water pan to keep make sure the heat is indirect.

[SouthamptonSmoker]

Brain fart I didn't cube the riser dimension, must be more like 800'' cubed to add.... Ill chuck it back in the calculator and see what it does

[SouthamptonSmoker]

So I chucked it back in and makes no difference. I see it is just a multiple of firebox size x0.008 - as the firebox hasnt changed then this value doesnt either.

My box is 150% size differential. So also means that the throat etc is all oversized as these are multiples of firebox not cook chamber. Would we think there would be a problem with that?

I guess the bottom line, is there is only one way to find out. I am going to go head and get the riser cut and light up the tig torch and start proceedings.

Got a week lead time on steel. It only commits me to the riser, so keen for any further advise before i hit go on the cook chamber.

Worst case scenario, I'll chuck an electric element in there and cheat lol.

[Dirtytires]

[/quote]

Is anyone able to provide some feedback on the above?

Thanks in advanced.
[/quote]

Well, honestly....no.

I think I speak for all when i say we are watching your build closely but am afraid that we are not going to be of much technical help. You are building a unit that we have never had experience with and the dynamics are completely different than what most of us build. So, unfortunately, that makes you the expert on this one.

I'm sure everyone will chime in when we can offer something but dont be disappointed if some posts go unanswered.

[SouthamptonSmoker]

I guess I just gotta to it lol and find out. It will be something for sure.

I think next weekend I should be able to start sticking things together, if it goes well, my drawings for rest will also be finished so should keep the work flow.

I am hoping to get it together for August 21st but that might be a tad optimistic

[SouthamptonSmoker]

Got the riser plates order. that will arrive for next weekend.

Been working on finalising the cook chamber, not far from complete now, latest updates for gas struts and latch.

The hinges have not arrived yet so I just mocked up a hinge with the pivots being about what the hinges should be. Wont be able to finalised completely until they arrive.

[mp4]

I like your gas strut and door latch system - very cool!

[pr0wlunwoof]

Gas struts might have issues with seals and temperatures. Might look at spring loaded instead.

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[SouthamptonSmoker]

Thanks.

The struts themselves are in a pocket outside of the cook chamber and door which are both insulated, so I am hoping it will not get too hot there.

[pr0wlunwoof]

In my experience insulation slows heat, but it has to be super duper good to stop it completely.

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[SouthamptonSmoker]

It is vermiculite 1'' boarding.... I also have a couple of thermal conductors in the way of the members. Which won't help either

I would certainty be concerned if we start to get much past 60 degrees centigrade, but I think they will cope with up to that.

I guess I might be doing the gas struts more for the look, and hope they work out

[inkslinger]

You could also just turn the latch sideways and split the door down the middle. Have it open out to either side instead of up. It is prob easy enough to find the specs on those hydraulics tho. There must be some documentation on how hot they can get before failure.


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[Pete Mazz]

Flipper doors will throw heat and smoke right in your face.

[SouthamptonSmoker]

Isn't that what you guys use on the round receiver vessel smokers? All the doors seem to open vertically.

There is a lip on the inside too, which would make it worst lol. As long as most of the heat stays in there. I guess I will have to live with.

I thought the general consensus was to keep them closed?

I can't turn it side wise without some issues. This was the only location I could get the door to overlap internal insulation and as such have no uninsulated sections. I try all locations, I don't want hinges mounted of the side plates, so everything starting creeping in and actually I would have to make the opening smaller and add further insulation on the cook chamber panels to make it work.

I would need a further 25mm one side for hinges but more like 80mm on the latch side. Then the opening would not be symmetrical. Which could affect my feng shui.

I guess this is the same as my current smoker. Which I certainly get a face full of smoke when I open, but that is half the fun isn't it?

[SouthamptonSmoker]

Flipper doors will throw heat and smoke right in your face.

That is a neat looking thing in your Avatar Pete, is that a build of yours? Would be interested to check that out

[SouthamptonSmoker]

Flipper doors will throw heat and smoke right in your face.

That is a neat looking thing in your Avatar Pete, is that a build of yours? Would be interested to check that out

Almost looks like a gas bottle bottom right?

[Chromeski]

Wow, just found this thread. Once I saw you were machining threaded rods I knew this was well beyond anything I'll build, but excited to see it finished.

[Pete Mazz]

Here's the thread.

http://www.smokerbuilder.com/forums/vie ... =17&t=4972

I've since added an electric element for cold smoking and made sturdier shelves .

[SouthamptonSmoker]

Here's the thread.

http://www.smokerbuilder.com/forums/vie ... =17&t=4972

I've since added an electric element for cold smoking and made sturdier shelves .

wow, good going, done in a month.

How did you get on with the stainless, did you go across large spans, and was the skin structural at all?

I am concerned about warpage, im pretty confident about the welding, patience is the key, but the inn and outer skin combined to essentially box section, so that is the structural part too. i would had to see it buckle first fire lol.

im using 3mm thick for the skins, 6mm for the baffle plate, not yet got to the firebox, but the oven will be 3mm, but instead of insulation, heat accumlation.

[SouthamptonSmoker]

Wow, just found this thread. Once I saw you were machining threaded rods I knew this was well beyond anything I'll build, but excited to see it finished.

Thanks. You will be surprised what you can do when you put your mind to it. Although this could still lead to disaster lol

[SouthamptonSmoker]

Whilst I wait to build the sample part, I decided to give my dad back his laptop, so drawing has stalled for a minute.

I have a few parts arriving we I need accurate dimensions off, I have cook chamber and door done more or less, so seemed a fair move, I have had it a while.

In the meantime I can start thinking about the bottom half. I ordered a solid brass ships wheel for a door handle on the firebox, this will be some 4 point system, which is geared, so you have to turn the handle alot to unlock, like water tight door.

I will leave it as it, polishing would ruin it. I want a patina.