# Reverse flow smoker build- 250 gal



## bnew17

I started this build around 15 months ago with no welding experience. I did a good bit of research and looked at a lot of builds and came up with an idea of what i wanted to build mine like. I did this build on a budget and luckily i was able to get everything very cheap and some for free. Between that, my daughter being born, and not having any big tools to do the cutting or lifting , it took me a while to finish. All i had for this project was a Hobart Handler 180 mig welder, a Dewalt angle grinder, and an electric drill. I followed the bbq calculator on the smoke ring forum to a T.

I needed a trailer but was unable to find one for a good price. Luckily a very good friend had 31ft of this 4"x4" square tubing he didn't want so that is what i used for my trailer. I was able to find an axle from an old mini van for 40 bucks and off i went building the trailer.







Another friend of mine gave me this 2"x4" tubing. It was only 10 ft long but i was able to use part of it for the tongue and the rest for a support to tie the tongue into the trailer frame











Getting the tank on the tank on the trailer was tricky with no hoists or other tools. I waited until my brother was able to come over and help. We put a t-post through the hook on the front of the tank and were able to pick the front end up and set it on the trailer and then gradually slide the tank onto the supports. The tank was HEAVY!!! You can tell by the t-post being bent like out of shape. 









I decided to go with 2 doors because of the sheer weight of each door. 1 big door would be too much. I marked off my doors with some chalk. I marked to top of the doors about 3" down from the 12:00 mark and the bottom of the door about 1" below the 3:00 mark. That way with my 1" tubing , the top of the grate would be at the center 3:00 mark.





Next i cut the doors out very slowly. I left 2" at every corner and the center of each side. I was worried the cutting out the doors too fast would cause the tank to "spring". I had read about this happening and i knew i didnt have the tools to fix a problem like that,,,luckily my plan worked and the doors came out fine. Next i welded some 1 1/2" flatbar around the edges of the doors. I decided to make my own hinges out of some 1/4" steel plate scrap. Nothing fancy just drilled a 5/16" hole in each hinge and welded a small piece of 5/16" round stock in place. I did order some spring handles. I liked the look of them in other builds and had no way to fabricate any so i bought 5 handles. I ended up cutting some more 1/4" plate and running some scrap rebar i had laying around through the spring and welded into place. 
      A family member of mine is in the well drilling business and i was able to get a few pieces of 6" scrape pipe to use for my smoke stack. I was glad to get my hands on 6" instead of 4" because 4" would have to be too tall. Cutting out a round hole on the edge of the tank with a angle grinder was probably one of the most aggravating parts of the build. Not only was it tough but fitting the pipe was tough as well. Eventually i got fitted perfectly. 
     Through my research of reverse flow smokers i found the majority of the reverse flow plates are welded 3"-5" below the grates. I decided to have my reverse flow plate 4" below my grate so i found the center line at the end of the tank and marked a line for my cut for the firebox. 













Next i had to weld in the supports for the reverse flow plate. I ended up using some 1" square tubing.





Fitting the reverse flow plate was very tough. I used some 1 1/2" angle for my drip channel so i cut my plate in 2 equal pieces. Each piece of plate weighed close to 100 pounds a piece and moving it by myself was tough so i tack welded some u-bolts in place for handles. That helped and i was able to fit them and tack them in place.





I landed the plate for my firebox at a scrap yard. It was an odd shapes piece but it was 3/8" and big enough for me to get (6) 27 1/4" square pieces , which worked out great because it was just about the exact size the bbq calculator called for. I beveled all the sides and welded into place. My grinder cut off wheels wouldnt touch this plate so i took the plate by a fab shop and they used a huge metal shear to cut the plate and also cut out the intake holes for me. I didnt have a way to make a 2" cut with my grinder so i got them to. I never thought i would finish welding this firebox. It was like the never ending weld. This firebox is HEAVY!!! 






I had no way to lift the firebox up to weld it to the tank so i had my neighbor lift it up with his tractor and hoist. I used flat black rust oleum paint. It took me a while to come up with a firebox latch handle design. I wanted something with a latch because they looked the best to me so i uses some scrap 1/4" and some left over 5/16" round stock. I welded a cutoff piece of rebar to the 1/4" stick and slipped a spring handle over it. I also decided to go with the same hinge design as i did with the tank doors.




























I had some angle left over so i welded some supports on the inside of the firebox door. I was worried it would warp if it got too hot





This was one heck of a project. If i had a plasma cutter it would have been sooo much easier. I nought a brand new dewalt grinder at the beginning of the project and burnt it up about 3 weeks ago. I limped to the finish line with a 29 dollar harbor freight grinder. I am going to add a fold out table the front of the tank at some point in the near future. I sprayed the inside of the tank and grates with pam spray for seasoning and ran a hot fire for 5 hours today. It sure was a GREAT feeling to see that smoke rolling out of the stack. The temps were good. I got it as high as 500 degrees and once i dialed it down to the mid 200's towards the end i only had a 12 degree difference from the front to the back. My first smoke on it will be some Christmas turkeys.


----------



## Dr. Strangelove

That's a great looking cooker! Nice write up, too.


----------



## VANCE

thats a great project

congrats


----------



## bluemarlin

That's awesome. Nice job on all of it!


----------



## GA1dad

For someone with no welding experience, and no tools,,,,,,,,, I'm highly impressed! It gives me hope that I will one day get mine finished too!!

Great Job!!


----------



## Gadestroyer74

Excellent post great work looks fantastic !


----------



## Gadestroyer74

One suggestion is some fenders over your tires.. Maybe some expanded metal on top of the 4x4 frame looks amazing though


----------



## shakey gizzard

I don't see any cup holders! Nice work!


----------



## jimbo4116

That is a great job and story.  I work around welders everyday and considering you built that with the tools you mention is amazing.

I would suggest to things.  Put in a gusset behind the strip between your doors.  Running up and down the road may cause some stress there. May never cause a problem but better safe than sorry.  Cap off the ends of your 4x4 tube to prevent internal rust.


----------



## dwg1

nice job, looks great lots of hard work, now the fun begins


----------



## dotties cutter

Gotta be a labor of love. You and family will enjoy that cooker for many years to come. Now you got to show some of the great vittles' that will be coming off that cooker.


----------



## Gaducker

Put you some kinda control valve on your exhaust pipe and you can overcome the 12 degrees difference with less fuel.     

I usually take a piece of flat plate cut just big enough to sit on top of the pipe with a small tab big enough to weld a 1/4 inch rod that will run down the pipe with two washers or nuts secured to the pipe .


----------



## Agent 732

Awesome job on the RF 250. I know I enjoyed building mine with my father in-law. Once you cook on it a few times, You'll have it fine tuned on what it likes!


----------



## 3ringer

I am impressed . How much do you think the total rig weighs. Also what is springing.  Is that when you cut out too much of the tank, it will warp. I haven't thought of that. Good job on the grill.


----------



## bnew17

Thanks everyone for the kind words. My welding is not the best but it seems to be holding up and getting better. I found some techniques on the internet of all places that worked well for me. Im still getting to know my welder. Getting the settings right for each setup is a little frustrating. My "in tight quarters" welding needs a lot of practice along with any welds that are not left to right haha. But those welds i feel very comfortable with.




GA1dad said:


> For someone with no welding experience, and no tools,,,,,,,,, I'm highly impressed! It gives me hope that I will one day get mine finished too!!
> 
> Great Job!!



Thank you. I really want a plasma cutter. Im going to work on getting an air compressor first, but those plasmas sure are $$$. Eastwood makes a plasma for a little cheaper ive looked at. Ive got a friend who is planning on getting one in the near future...i may just see how it works out for him.



Gadestroyer74 said:


> One suggestion is some fenders over your tires.. Maybe some expanded metal on top of the 4x4 frame looks amazing though



I think that would look good. I wonder if i could find a couple used ones at the junk yard?



jimbo4116 said:


> That is a great job and story.  I work around welders everyday and considering you built that with the tools you mention is amazing.
> 
> I would suggest to things.  Put in a gusset behind the strip between your doors.  Running up and down the road may cause some stress there. May never cause a problem but better safe than sorry.  Cap off the ends of your 4x4 tube to prevent internal rust.



Thanks for the suggestion. I do have some left over plate i can cap off those ends with.



Gaducker said:


> Put you some kinda control valve on your exhaust pipe and you can overcome the 12 degrees difference with less fuel.
> 
> I usually take a piece of flat plate cut just big enough to sit on top of the pipe with a small tab big enough to weld a 1/4 inch rod that will run down the pipe with two washers or nuts secured to the pipe .



I had planned on putting something like that on the stack but never could figure a good way to secure it to the stack. Like something to run the rod through that i could weld to the stack to keep it in place.



3ringer said:


> I am impressed . How much do you think the total rig weighs. Also what is springing.  Is that when you cut out too much of the tank, it will warp. I haven't thought of that. Good job on the grill.



It weighs ALOT. I think i have read where the tank alone weighs 500-600 pounds. The firebox weighs roughly 480-500 pounds . I would say with everything its got to be pushing 1400-1500 pounds. 

Springing is when you cut out something on the tank. Usually a door, and the tank springs back and loses part of its form from all the pressure put on it when it was rolled and welded. I know its thats not the best explanation but i kinds gets a bow to it. Ive read where people have had this happen even on old tanks like mine. I believe mine was stamped in the 60's.


----------



## Gaducker

I had planned on putting something like that on the stack but never could figure a good way to secure it to the stack. Like something to run the rod through that i could weld to the stack to keep it in place.



That's what the two nuts or washers do, They wont let it move, only rotate


----------



## Gadestroyer74

You could find some in a junk yard or some one who has a old junk trailers around you might have to cut them off and self them on yours when you pull it it's go a throw mud water etc all over your smoker. The expanded metal would close of the bottom to keep things on or lay on and give it a finish look I really like it and admire your work real good job


----------



## Jeff C.

Great job considering the tools used and your fabrication/welding experience! Great write up too! While we're at it, I bet some Great eats will come off it also!


----------



## cramer

Great job and great looking smoker!
I can't wait to see some of the results of your cooking


----------



## 7Mag Hunter

Nice !!!!!!!!!!!


----------



## Moonpie1

Great job with the cooker!! Looks like you got your welding down pretty good. One suggestion. On your slide out grates, weld a stop and piece of angle to keep from coming out too far. And to prevent tipping when it's loaded with meat.


----------



## Agent 732

mine before it was done...hope this helps


----------



## Moonpie1

Another trick with the doors is to cut area where the hinges attach. Go ahead and weld them on then finish cutting doors out. Then you don't have to wrestle with them to line up doors and hinges. Just an after thought if you help some one with another one.


----------



## papachaz

wow that is a great build and write up!

for your stack cap, you could just weld some threaded rod sticking out of the inside of the stack an inch or so, drill a hole in the top plate for the rod to slide through. find a spring to fit over it, put a washer on top of the spring and a nut on top and voila, there ya go.

also, on the doors. Being so heavy you have a couple of options. Those pneumatic type shocks like on the inside of most car hoods, OR some kind of counter weight welded to a rod/bar from the door off toward the back.

also you can check tractor supply for trailer supplies, they have a variety of fenders, or, etrailer.com


----------



## 3ringer

Moonpie1 said:


> Another trick with the doors is to cut area where the hinges attach. Go ahead and weld them on then finish cutting doors out. Then you don't have to wrestle with them to line up doors and hinges. Just an after thought if you help some one with another one.



Smart idea


----------



## SapeloJoeBro

Great smoker and thread.  Well done.


----------



## Paymaster

Great job! That rig looks awesome, congrats!!!!!!!!!!


----------



## tsharp

Very nice !


----------



## tsharp

I have worked on my smoker too. These is how I made my vent cap. Hope this helps.


----------



## lbzdually

bnew17 said:


> It weighs ALOT. I think i have read where the tank alone weighs 500-600 pounds. The firebox weighs roughly 480-500 pounds . I would say with everything its got to be pushing 1400-1500 pounds.



I'm hope I'm wrong here, but having that much weight (firebox) hanging behind the rear axle, then the tank just slightly forward of the axle, might cause the trailer to tip if not attached to a truck.  This is especially true if you have a firebox full of wood and someone steps anywhere on the back of the trailer.  I would put a small flip down jack as far back as you can to stop this from happening.


----------



## bigelow

wow..... nice very nice


----------



## merc123

Really nice.  Looks like you even used a stick welder and that in itself is a feat for someone that has never really done this kind of thing, I think.

Did the tires get any heat in them from cooking?


----------



## Palmetto

Awesome! Thanks for sharing and I can't wait to see the meat coming off of that thing!


----------



## big ike

Nice job on the smoker!! made a few of these my self.
as a retired welder and fabricator I can't imagine making that many cuts with a grinder or maybe I missed something in your list of tools used.. gotta ask... how many disc did you use ??
  need to put a lid stop on it, looks great!!


----------



## bnew17

Agent 732 said:


> mine before it was done...hope this helps



Thats exactly what ive been wanting to do but i cant find any pipe like that to run the rod through. We have a fab shop that would have it probably for an arm and a leg but they are rude and i refuse to buy from them. 



merc123 said:


> Really nice.  Looks like you even used a stick welder and that in itself is a feat for someone that has never really done this kind of thing, I think.
> 
> Did the tires get any heat in them from cooking?



I was curious at how much heat the tires would get especially with the support thats welded to the trailer frame from the firebox, but they dont even get warm



big ike said:


> Nice job on the smoker!! made a few of these my self.
> as a retired welder and fabricator I can't imagine making that many cuts with a grinder or maybe I missed something in your list of tools used.. gotta ask... how many disc did you use ??
> need to put a lid stop on it, looks great!!



I had planned on a lid stop but it completely slipped my mind. Ive got some chicken and turkey on there now and its kinda tricky holding the door, flipping the chicken, and holding the light on my mouth! I have gone through a TON of disc. I have got all of them at harbor freight for dirt cheap. I would say i have used 60-70 discs. Enough that i burnt up my dewalt grinder about a month ago.


----------



## merc123

bnew17 said:


> Thats exactly what ive been wanting to do but i cant find any pipe like that to run the rod through. We have a fab shop that would have it probably for an arm and a leg but they are rude and i refuse to buy from them.



Tractor supply might have some. I just bought a stick of solid, zinc plated rod for $2.99.  Home Depot also has some.


----------

