Tennessee reverse flow project 2020

[Tigit]

Good morning everyone. I’ve been doing lots of research lately and will be starting a a 120 gallon propane tank reverse flow smoker. The tank is 28’ diameter and it’s about 46” when lying horizontal. I bought a 24x24x24 3/8” thick firebox already built for next to nothing at the local scrap yard. PitCalc tells me it’s at the current size I’ll be 150%, but if I cut it down to 21x24x21 I’ll be at 114%. I am going to be installing some kind coal/split basket and ash tray, do I really need to cut it. I’ll be using 2 2x8 vents, one on each side of the smoker and a 5” ID pipe for the stack. Thanks for the help! I’ll be posting photos soon.

[Tigit]

Haha 28” not 28 feet!

[towtruck]

What about insulating it to take up some of the room and helping maintain temps better....Even if you line it with brick that would take up space and help hold heat....just a thought.

[Big T]

you could add a false floor to the FB to take up some space or use fire brick but I'd definitely cut the volume down some.

[Dirtytires]

Ditto.....150% is too big.

Could always get a bigger cook chamber chamber....

[Tigit]

Thanks for all the responses towtruck, Big T, and Dirtytires! Haha I did think about cutting a second lp tank and stretching the cc to make the firebox work! I could put fire brick on the sides and bottom inside some type of frame, I’ll work on doing some drawings to see what I can come up with, that’s a great idea! Next week I should be able to post some pics of the tank and firebox. Thanks again, and I’ll talk to you soon!

[Tigit]

I decided to trim down the fire box to 21” tall x 24” wide x 21”deep. This gets to 114% and change for the 120 gallon propane tank. it’ll take a week or two since I’m working on this at school during the week. I’ll get some pics as I’m working on it.

[Dirtytires]

Good plan....set it up properly or you will be fighting it every time you run it.

[bowmanjk243]

For what is"s worth - 24 square is the same size I have on my 120 gal RF. It is 1/4 plate as well. Runs like a dream and wouldn't change a thing. does a 10 hour smoke with minimal wood, flows perfectly and holds steady at about 250 consistently, unless really cold out. I did install fire brick in the bottom so that does take up a little bit of the space (1 inch across the bottom). Not to say I don't use the calculators (good starting point), but proof is in the pudding. Attached pic of another one I am doing for my father as we speak with the same specs. BTW - I am right outside Cookeville, TN if you ever want to check them out for ideas.

Current 120 RF Build

[Tigit]

Bowmanjk243,

Thanks for the invite, and the info. I was listening to the podcast and Frank was talking about airflow in the firebox and vent location relative to the log rack. I have already cut three inches off the depth. The FB is now 24 wide x 21 deep and 24 tall. There is about 4 inches below the log rack and I will probably cut a inch and a half to two inches off to keep that space below the rack to allow airflow up and through the coal basket that sits on the rack. Are you running a 5” stack?

[bowmanjk243]

Tigit - my stacks are 4.5 ID and if I remember right 27 inch in length. I constructed a single pie vent on the FB door for air intake which gives you two 3.5 triangles if fully open. Once it is up to heat and leveled out I only have to crack them about an inch, at most. My rack is a simple storm grate from the metal scrap yard and welded 3 sticks of 1" square on the bottom of it for air gap. I cook a lot on it and it hasn't warped any yet after about 9 years. When I built first one, I didn't have all the calculators to use for specs. If you ran what I did through the calculators now it is way off on the FB and stack. Everything else is on par. That said, it works... very well IMO. To the point I am using the exact specs for the one I am building my Dad now. Once had a friend with a new Lang 60 try his hardest to get me to trade because he loved how smooth mine ran. Guess I just got lucky, but IMO there is some wiggle room in the set up. Can always strive to make them more efficient though, which is what makes this fun. BTW - I have unlimited supply of seasoned hickory and oak off my property. I believe having "good" wood helps for a smooth burn and is probably often overlooked by some. I start with about a half bag of Kingsford and 3 splits. Usually up to temp in about 40 min and then it only takes a couple splits every 1.5 hours or so. Guess it depends on what your definition of "efficient" is. Always wanted to run it side by side with one built to exact calc specs to see what, if any difference there is. That would be interesting and fun. What part of TN you in?

[Tigit]

bowmanjk243 - I’m in Lebanon, we should definitely meet up sometime. I’m hoping we can get a break in the weather so I can work on the smoker more at school. It had been raining most of the week and we do our grinding outdoors, so I was working on other projects. I’m in the process of prepping my pole-barn for concrete and getting the slab poured in the next week or so. Once that’s done, I’ll be working hard to get everything done on the inside so I can work on it at home. Yeah, I imagine the calculators ate to help get you get really dialed in...you know there were tons of folks before us, who never had the calculators and were cooking up really good bbq! No thing like experience and trial & error!

[bowmanjk243]

Tigit - no doubt. If you run the high end Jambo pit dimensions on the calc the FB comes out to about 179%.. lol, Yeah, your not far down the road. Had my last tank sandblasted there last month. Keep me updated. Trying to get caught up on projects myself between all the rain.

[Tigit]

It has been a long time without a post...everything went all stop after he tornado in our area. We are all good, lots of work to do on the property with trees and downed limbs. My school was shutdown for Covid-19, so no work on the smoker. I have been working really hard to convert a pole barn into a shop and have framed the walls, insulated, put up 3/4 osb subfloor for the walls, painted, foamed, caulked, and had an electrician work his magic! I’m expecting the final inspection very shortly, then the electric company can hook the shop up to the grid. Sorry it’s been so long y’all! I should be up and running in the next 2-3 weeks and have the smoker back at home from school to work on. Cheers!

[Big T]

Glad to hear that you made it through the storm. We all know that life gets in the way of our hobbies at some point so don't lest that get you down.

[Dirtytires]

Get back at it! The weather is perfect to get the smoker out!

[Tigit]

Thanks Big T and Dirtytires! The electric company should be here today or tomorrow and that will help. I get to start school again on the 19th, and should be able to do a little more welding on the FB and then do my layout and cutting for the throat in prep for join it to the CC. Once they are joined I can get them on the rolling stand and bring it home and do everything else. I’ll post more for sure and maybe a few pics next weeK.

[Olibinoui]

For what is"s worth - 24 square is the same size I have on my 120 gal RF. It is 1/4 plate as well. Runs like a dream and wouldn't change a thing. does a 10 hour smoke with minimal wood, flows perfectly and holds steady at about 250 consistently, unless really cold out. I did install fire brick in the bottom so that does take up a little bit of the space (1 inch across the bottom). Not to say I don't use the calculators (good starting point), but proof is in the pudding. Attached pic of another one I am doing for my father as we speak with the same specs. BTW - I am right outside Cookeville, TN if you ever want to check them out for ideas.

IMG_1942.JPG

Wow nice one!! Looks great, do you stand on the trailer while cooking this beast?