Reverse Flow Smoker / BBQ Pit Project - Lots of Pictures

[rl.robertson]

Hey guys- I haven't been on the forums in a while, but thought I would throw this out there.. I searched and searched for plans to make one of these, but ultimately had to design most of it. Even the wheels were fabricated. It is a reverse flow smoker, so the temperature only varies about 5 degrees from end to end. I had around $550 in the project, but everything that is exposed to heat is at least 1/4". The Lang's are going for 1500+. It's a beast to move, weighing over 500 pounds! Hoping it'll give someone else ideas if they're looking to build a reverse flow smoker.


http://farm9.staticflickr.com/8388/8...81e18a2c75.jpg

18" diameter, quarter wall water pipe found on craigslist.

http://farm9.staticflickr.com/8388/8...6a76aeaca1.jpg

12" pipe was cut down with a band saw to make the outer ring. Cut the spokes, and will sleeve pipe with bar stock for the axle.

http://farm9.staticflickr.com/8526/8...856da8245d.jpg

Tape was an awesome way to mark where the lid would be cut. I then cut flat soaker hose a few inches larger than the pipe diameter, clamped it, and used that as a plasma torch guide.

http://farm9.staticflickr.com/8520/8...4f19bafee9.jpg

Door cut, and trimmed out- weld the hinges on BEFORE you cut the entire door out.

http://farm9.staticflickr.com/8245/8...1407023a27.jpg

Reverse flow plates installed- I actually ended up raising them up about 3", but this is the only clean picture I have of it. Make sure that the fire to chamber entry is at the top of the firebox, not part way up. Otherwise it won't draw correctly.
http://farm9.staticflickr.com/8365/8...79e07754e2.jpg

Cooking rack / grate installed
http://farm9.staticflickr.com/8378/8...e75e9be999.jpg

Fire box door in the works. I used a vent I bought from etrailer that is used for the top of livestock trailers. Works perfect to regulate the air intake. Cheap to replace.

http://farm9.staticflickr.com/8366/8...887a47023a.jpg

Finished wheels close up

http://farm9.staticflickr.com/8520/8...535996391e.jpg

Finished- and painted!!

http://farm9.staticflickr.com/8237/8...cb1241858a.jpg

And the best part..

Email or PM me if anyone is needing any details on building one. Reverse pits in this thickness go for 1500+. So glad I took it on myself, and now I have a pit that will outlive me.

[Bistineau]

That's a nice looking rig you built for sure, and extra heavy duty wheels too. May need another pair up front to make moving it easier. If you close in the bottom shelf on 3 sides with expanded metal, you can store your split firewood down there to have it handy where ever you move the grill to for cooking. That's what I did with mine, and I don't have to move the wood seperately when I move the smoker, it's all right there in one move. Since you made the top of your firebox flat you can cook a pot of something there, which I'm sure is what you had in mind when you made it, but you can also preheat the wood that you are going to use next to help get the fire hotter if you need to. What paint did you use for the finish? I don't think I have seen gloss heat resistant paint before. Looks good though, when is the next cooking, and need driving directions.

[elvis]

x2 on the directions. I can be there in about 2 days. Give or take. I can't wait!

I'm actually just putting materials together to build a little bit bigger version of that. Smoke chamber will be 24" sch10 pipe. I'm going to put the firebox directly underneath and the divert the smoke/heat around to both ends.

Do you have any tips before I build mine? Any issues that came up during the build?

[rl.robertson]

What paint did you use for the finish? I don't think I have seen gloss heat resistant paint before. Looks good though, when is the next cooking, and need driving directions.

Never thought about pre-heating the wood.. I've been using the flat top to cook garlic corn, or whatever else we want to go with the meat.. That's a good idea. For the paint, I used the high temp rattle can paint for grills.. I think it was rustoleum, but don't have any left to verify. I remember there was 2 kinds, and I used the one that cost a little more. It has a nice gloss to it. On the firebox, just above where you load the wood, it is burned a little. After a smoke while it's hot, I like to rub it down with PAM spray on a cloth- seems to season the pit like a cast iron pan. So far though it has held up great; and I get the cook chamber up to 375 after a smoke to clean it.

x2 on the directions. I can be there in about 2 days. Give or take. I can't wait!

Do you have any tips before I build mine? Any issues that came up during the build?

There will have to be lots of practice before it's worth a 2 day drive! haha.

24" will be a nice pit!! I can get about 3 briskets on mine, wish I could've went bigger, but for a rolling backyard pit, that's about all I figured I could manage.
Cutting down the material was a beating.. Eventually, I used a section of that flat rubber soaker hose that you use in flower beds. I cut it a couple inches longer than the outer diameter of my pipe, and clamped it really tight since it had some stretch to it. I used that as a guide for my plasma torch. It yielded a better cut than free handing it. I also used that for cutting the curved areas of my door. I just clamped a 2x4 down for the horizontal door cuts, since it was closer to flat.

http://www.thesmokering.com/forum/viewtopic.php?t=20871

I used that pit calculator.. your ratios don't have to be exact- in fact I made my firebox a little bigger since it is reverse flow, and I knew it would take more to keep the heat going down and back. That will help you figure the right proportions though. Before you cut your doors- I cut out just the area under where the hinges would be welded, then welded my hinges on with the rest still uncut. Then, you can cut the entire door. That way when you cut the door, you're not trying to get it realigned, it's already perfect since you have the hinges welded. That will save you some time. Also, if you make your own hinges, make sure you aren't sending the weld current through them.. I learned the hard way that it will arc inside of the sleeved hinges. Had to redo mine on the firebox door. I didn't do fancy dampers, or other internal regulating mechanisms.. I use the air intake damper, and the stack damper and I can keep her anywhere between 160 and 375 degrees.

If you make your own wheels, make them bigger than I did. It would have been much easier to roll it over things if I'd went with 16" wheels at least.

Keep us posted on the smoker! Lots of guys are swearing by the vertical ones. That's the big issues I can think of, but if you run in to something else let me know. I'm no expert, but I learned a lot through trial and error on that one.

[kevhead63]

Looks real good, nice job.

[weld on]

Looks really nice. I like the handles on the plates and the custom wheels. Glad you posted this, gets me motivated to modify my offest to a reverse offset. Should be a fun project, on mine the firebox and opening need to be lowered to accommodate adding the plates.

did you put any slope on the plates themselves for grease/liquid drain or did you put a little slope on the whole barrel?

[Guesswho392]

Looks great thanks

[elvis]

Okay, I have some pipe now! How did the soaker hose work for a plasma guide? I've got some sch20 24" pipe and it is 3/8" thick. My little tiny plasma will not pierce that, but I can edge start. I think I'll drill a start hole and then plasma cut it using your soaker hose guide idea. I like that!

BTW, .375 wall is going to be awesome once it is complete, but it is very heavy and bulky!

[rl.robertson]

Okay, I have some pipe now! How did the soaker hose work for a plasma guide? I've got some sch20 24" pipe and it is 3/8" thick. My little tiny plasma will not pierce that, but I can edge start.

Awesome!! That's some hefty pipe.. You'll like it though- being that thick it'll take a bit to get up to temp, but it'll hold and regulate heat like nobody's business.

I was looking around for something flexible to clamp around when I cut my pipe, and my neighbor had a sprinkler hose he was throwing out. It's flat, rather rigid, and thick. I thought I'd try it since it was trash anyways. I put a link in below so you can see what I'm referring to.

soaker-sprinkler-hose.jpg

If you have at least one squared end to work off of, then just measure in whatever distance you're wanting the cut, and mark it in 6 or so places.. Then cut a length of that style hose or whatever else you can find just about 4 inches longer than the OD of the pipe. I stretched it as tight as i could, and clamped the ends together following my guide marks. As long as you run the torch against it with little pressure, it stayed in place fine for me as an edge guide. The heat melted parts of the trailing edge to the pipe, but a wire wheel on the angle grinder cleaned it off in a hurry. Initially I tried free hand, but went back with that hose, and took off about 1/2 inch to get it near perfect. That really made my end caps go a lot smoother. (Smaller gap to fill)

(Looking at your footer) I have the Cutmaster 42 as well, and that's what I used to make my Grillzilla. Awesome torch for the price. Make sure you got the 40 amp drag tip on there when you're cutting that thick of material. I learned quick that the smaller amp tips don't work when trying to cut that thick of material.

Keep us posted on your pit build! Building it is just as much fun as BBQing on it!

[elvis]

Awesome!! That's some hefty pipe.. You'll like it though- being that thick it'll take a bit to get up to temp, but it'll hold and regulate heat like nobody's business.

I was looking around for something flexible to clamp around when I cut my pipe, and my neighbor had a sprinkler hose he was throwing out. It's flat, rather rigid, and thick. I thought I'd try it since it was trash anyways. I put a link in below so you can see what I'm referring to.

soaker-sprinkler-hose.jpg

If you have at least one squared end to work off of, then just measure in whatever distance you're wanting the cut, and mark it in 6 or so places.. Then cut a length of that style hose or whatever else you can find just about 4 inches longer than the OD of the pipe. I stretched it as tight as i could, and clamped the ends together following my guide marks. As long as you run the torch against it with little pressure, it stayed in place fine for me as an edge guide. The heat melted parts of the trailing edge to the pipe, but a wire wheel on the angle grinder cleaned it off in a hurry. Initially I tried free hand, but went back with that hose, and took off about 1/2 inch to get it near perfect. That really made my end caps go a lot smoother. (Smaller gap to fill)

(Looking at your footer) I have the Cutmaster 42 as well, and that's what I used to make my Grillzilla. Awesome torch for the price. Make sure you got the 40 amp drag tip on there when you're cutting that thick of material. I learned quick that the smaller amp tips don't work when trying to cut that thick of material.

Keep us posted on your pit build! Building it is just as much fun as BBQing on it!

I know it could be interesting to get up to temp. I'm thinking about also building a cross style propane burner to get to work going quicker. I did a bunch of freehand cutting with my 42 of .5" plate. That was fine because I had to go so slow. .375 should go a bit faster and I like the guide you came up with!

Thanks for the suggestions!