Octagon Offset Build (24" x 48")

[SNeal5966]

Hello All....

I have started a new project, building a new offset smoker for myself, using 1/4" thick plate. Here is where I am at so far....body is fully welded together, no end plates yet, door is cut and is partially fabbed. Firebox is welded up ready to attach, no grating fabbed or installed yet, no frame for it either. This thing is going to be on 10" swivel casters with 4" wide pneumatic style wheels (flat free) so that navigating around the yard won't be too bad. I made the panels 10" which makes the internal width 24". I did make the 2 vertical panels 12" though to give me some more spacing between my grates. The firebox is 24" cube. The exhaust will be 6" cube. The inlet to the firebox, 2 - 6" holes, will have slider vent covers on them. I wanted the ability to have a lot of air flow for higher temps when I want to.

 

[SNeal5966]

Sorry Minor typo....6" tube exhaust, 1/8" wall thickness...not cube....;)

 

[JckDanls 07]

Yea.. I'm along for this ride (I think my next build will be octagon)... what's the length of the smoke chamber ?? conventional or reverse flow ?? Looks great so far...

 

[SNeal5966]

Thanks!

The length is going to be 48", and I am going to go traditional offset with tuning plates. The Octagon gives you some added benefits, you can make those center panes even taller if you like, which will give you even more spacing between the racks. I should have about 6.5" between rack surfaces, and 6.5" between second rack and lid inside. I could have gone even taller in the center section....just wanted some extra spacing without adding a tone of temperature differential though.

 

[JckDanls 07]

LOL... I read the thread three times to make sure I wasn't missing the Length... then looking at the recent post page I see it in the title ...

 

[SNeal5966]

Its ok no worries.

I am going to make the grates slide out style too....I had drop in grates on my smaller smoker I had and I hated that.

 

[JckDanls 07]

Something you might want to do on the slide out grates... If you go to my build (link in signature) and look at the grates (click pic to enlarge) you'll see a little piece of 1" angle welded on the top of the track (both sides have it but can only see the right side in picture).. It serves two purposes... 1st being it stops the grate from falling/tipping down when grate is pulled out... 2nd... it serves as a stop.. I have a piece of 1" flat welded on the back side of the grate (sticking up) so it catches when grate is pulled all the way out... I then ground down the top of the one on the grate just enough so it still catches but also be able to lift/tilt the front of grate upwards for the grate to come all the way out ... It works really well and no intrusion onto grate space ..

 

[nanuk]

Just thinking out loud here...

is there any reason you can't go with a square bottom, so the transition between the FB and CC is a rectangle full width?

It would seem to me this could aid in evening temps front to back.

and would also simplify the build.

 

[SNeal5966]

Well funny that you point that out....I thought about going with a square bottom for ease of construction, and less welds....except believe it or not that uses more steel. Also.....my firebox opening into the cook chamber will be full width, so I am not expecting a lot of front to back gradient.....planning on using tuning plates for getting side to side under control.

 

[SNeal5966]

Something you might want to do on the slide out grates... If you go to my build (link in signature) and look at the grates (click pic to enlarge) you'll see a little piece of 1" angle welded on the top of the track (both sides have it but can only see the right side in picture).. It serves two purposes... 1st being it stops the grate from falling/tipping down when grate is pulled out... 2nd... it serves as a stop.. I have a piece of 1" flat welded on the back side of the grate (sticking up) so it catches when grate is pulled all the way out... I then ground down the top of the one on the grate just enough so it still catches but also be able to lift/tilt the front of grate upwards for the grate to come all the way out ... It works really well and no intrusion onto grate space ..

Yes deff, I am going to have stops like that for my grates so they will self hold weight when out all the way.

 

[motocrash]

Welcome from Virginia SNeal.Diggin' the build man!

 

[SNeal5966]

Welcome from Virginia SNeal.Diggin' the build man!

Hey thanks man!

 

[SNeal5966]

OK so this weekend has been productive......made some more progress....nearly ready for paint.... Just need an exhaust pipe installed, make up my grates, bottom shelf on the bottom frame, stops for the cooker door, push/pull handle to push it around....etc. Should be able to wrap this thing up next weekend and then get it seasoned up.

 

[JckDanls 07]

Looking great... will be interesting to see if the grate stops aren't to long .. I tried longer ones and found that the grate won't lift up in the front high enough for the stop on the back of the grate to clear the long stop on the side... maybe you have a different idea ... Gonna be a nice smoker though.. nice job ..

 

[SNeal5966]

I am going to put a 1/4" - 20 bolt, some type of thumb screw head or wing nut type head or something (whatever I can find at the hardware store in stainless) into the corner of each grate as a stop to keep it from falling out too far forward, that way I Can easily remove the bolt to remove the grates. I wanted the pockets to be nice and long to keep the grate from being tippy when it pulls out, that way I don't end up with brisket on the ground lol. You'll see what i mean with the photos I will post once it is done. This is turning out to be much more work than I thought.

 

[motolife313]

Nice build! That’s going to be a lot of fun to use. Mine was too top heavy and I widened the heavy side of the smoker with a custom built axle. No need to worry about heavy wind or anything

Here’s mine

https://www.smokingmeatforums.com/threads/stainless-smoker-build.251222/

 

[SNeal5966]

Hey thanks! You'rs is pretty cool too!

I sadly did not make any progress with finishing mine up this weekend, took a weekend off of it. I will be finishing mine up next weekend.

 

[SNeal5966]

OK so this weekend was a big weekend with lots of progress. It took all day Saturday, finished all the outside stuff and put the paint on it Saturday. I spent up until about 1 PM Sunday morning finishing up all the odds and ends for the internals....making up my grates, tuning plates (4 of them 5" wide), adding the 1/4"-20 stainless socket head bolts into the corners to act as my stops, added the gaskets to the doors, and installed all my hardware (temp gauges, probe port plugs, spring handles, etc after paint dried next day) Starting at aroung 1 pm into the into the evening I was able to get it cleaned up and coated with cooking oil and seasoned up and had it up to temp for about 6 hours, ran at 300 F for the last hour. I also ended up making the firebox grate slide out so that I can use it to start my chimney for getting the fire going. The food grates are 1-1/4" 3/16" angle stock and the grate is made out of 3/4" no 9 expanded metal, which is rolled smooth. The firebox grate is made out of 2" x 1/4" angle stock, and half inch re-bar welded together to make a grate. That grate weighs a ton but should hold up to the abuse from the fire for many years.

While I had the fire going I played around with the tuning plates a bit, got it pretty close end to end, within 5 - 10 degrees. I think I might actually have to remove one of them, seems like the middle is cooler (will know once I use my probes on the next fire), need more time on it though to know for sure. I started out with my first guess as to where they should go at about a 50 degree differential from end to end....not too bad for a guess.

Check out the wrap up photos on this build. The next time I have a fire going in this beast I will be cooking with it! (will put some bbq photos up too once I get to cook on it.

 

[SNeal5966]

I forgot to mention....my small side shelf and pull handle, as well as that chimney cap, are also easily removable for storage / transportation. They just lift out of the pockets.

 

[SNeal5966]

Ohh one other thing, the inlet vents are 2 x what I need, one on each side. Depending on wind direction you can crack one or the other or both for whatever you need. Very versatile. Also can get a wide range of temps. I can easily run higher temps like 300 - 350, and still have good control for the 225 to 250 range. For most of my paint curing / seasoning I ran at 250 nice and steady. I did get it up to 300 for the last log that I put on until she started burning down an hour or 2 later.