You might consider using something other than a domestic propane tank for your firebox since I think the steel on those tends to be pretty thin which isn't great for the efficiency or longevity of a firebox. My goal was to make a simple, traditional offset smoker that was very fuel efficient and maximized airflow in order to maintain a clean burning fire. I found that Mineral Spirits sort of liquefy it, making it easy to rub off with lots of old towels. I used 1" x 1/8" flat stock for these door seals and progressively clamped and welded down the door to match the curvature. The first step is to cut all the sides of your box. (VERY GLAD I DID). Question Hope that helps! Would it be possible to use the regular domestic cylindrical one for the fire-box and a bigger 5ft small commercial one for the cook chamber?Looks like attaching the two will be the most headache.Many thanks for the inspiration and congratulations once again on an excellent smoker. From that line you want to cut straight down and around the tank to create a half moon shaped opening. The rate of combustion is easiest to control in the stool-grate design and most difficult in the hearth bottom-grate type. 2 months ago. Thanks in advance. Cut along the lines you marked with an angle grinder and a cut off wheel. A good rule of thumb for sizing your firebox is to make it roughly 1/3 of the volume of your cook chamber in order to provide enough heat for you cooker. It is also a good idea to weld your hinges onto the door before you finish cutting it out so the door remains in alignment. You can have a steel supplier do this for you to make it easier but you could also cut it yourself using a metal cutting circular saw or a cutting torch. Make a rectangular frame with the square tubing to support the expanded metal then weld it all together. $2800 Now comes with Firebox top grill! 250 gallon reverse flow smoker, (2) 30 x 60 slide out racks (3) rack warmer, holds 6 pans 1/4” firebox non insulated $2,200.00 500 gallon reverse flow smoker, (3) 35 x 77 slide out racks (3) rack warmer, holds 6 pans 1/4” firebox non insulated $2,700.00 Insulated firebox $200.00 LP gas assist on firebox $100.00 Design and 3D Print Your Own Phone Case (in Fusion 360), https://www.homedepot.com/p/Mueller-Global-1-in-Black-Malleable-Iron-Plug-521-805HN/100165402, Square Tubing (firebox and cooking grates). Now that the firebox is finished you're ready to attach it to the cook chamber. You want to use thick steel is it will keep the temperature stable and easy to maintain. Hopefully this calculator will help you with the calculations. I cut these pieces out with a jig saw but you could also use a cut off wheel on the grinder if you don't have a jig saw. Needless to say we still need to add sawdust or wood chips into the hot coals. Note in order for the dampers to perfom their designated function, the fire box and its door must be made tight. The efficiency will further improve if the secondary air in C is preheated. I can't exactly remember the size of the round bar I used but I'm pretty sure it was ½". This smoker is a beast! Question I don't think these are really necessary as I can easily control the temperature by opening and closing the firebox door and controlling the size of the fire but many people like having these features to fine-tune their temperatures. 288 Gallon Tank Smoker. Full 10 page set of smoker plans drawn with Auto Cad for you to build a smoker. For years, these hunka-hunka smokers—a.k.a., offset barrel smokers, horizontal smokers, pipe smokers, or “stick-burners”—have dominated the competition barbecue circuit. The firebox becomes the hearth bottom-grate type and by adjusting the top damper we can choke down the air supply and the wood will start smoking. My friends, Charlie and his son Levi did most of the cutting and welding on this project and I for sure could not have done this without their help. The entering air below the wood has a greater density than the hot air above the wood, this creates a difference of pressure (draft) and the only possible way is to go up through the wood. There is a small gap between the two doors which I later welded a small piece of expanded directly to the angle iron in order to increase my cooking area. However, do not cover the top of the firebox yet as you'll need the ¼" plate exposed for welding onto the cook chamber. How well does that ceramic insulation work? Call or Email for Pricing. Using concrete blocks or masonry bricks will only make a temporary arrangement as they will start cracking. Gary Smith BBQ pits and smokers. Once you've got all your pieces cut out you're ready to weld them onto the tank, starting with the bottom plate, the pipe, then the side pieces and top. A piece of firewood or a water pan seems to work pretty well when you’ve need have meat right up to the firebox. A metal box of suitable dimensions can also be used. I had a friend brake a couple of pieces so I didn't have to weld everything. Another useful addition is adding a grate to the firebox to help air flow around the fire or adding a layer of firebrick to help with insulation. 2 years ago. The smoke cannot go straight up the flue anymore and has to return to sneak through the only available opening where it picks up fresh and hot secondary air and burns cleaner now due to much higher temperatures. The firebox design is further enhanced by sloping the floor of the firebox from the sidewalls down to the grate. If you're going to insulate the firebox the next step is to weld some square tubing along the sides your going to insulate. You can also paint your smoker to protect it from rust but you definitely don't need to. You can make door handles in much the same way you made the hinges. Can not decide if I am going to paint or leave natural. Its on a trailer and is in good condition. 2 months ago. The unit will have higher efficiency and less wood will be consumed. Even know what I am talking about? I am gonna try to build this smoker! I would recommend using ¼" for the whole firebox unless weight is a big issue for you. putting a sub floor by: chipster . Make sure to jump around with your welds on the expanded metal so you give the metal time to cool and don't cause any warping in the grate. building a 250 gallon reverse flow smoker This is the building process that friends and I used to build a 250 gallon reverse flow smoker and put it on a trailer. That's a fantastic piece of kit. If you want to increase your cooking surface you could easily add more shelves above the bottom ones. When wood is placed directly on the ground the whole air enters frome above. You'll want the firebox to be roughly a 1/3 the volume of your cook chamber. I'm in the process of building one and I would like to know the dimensions of the firebox. 250 GALLON PROPANE TANK!!!!! Using concrete blocks or masonry bricks will only make a temporary arrangement as they will start cracking. I am selling my 250 gallon offset smoker. A 250 gallon tank has about 57750 cubic inches in it. First, tack weld the tube just above where you will cut out your door. Once you've got the box all welded up you can cut out the opening for the door and the connection to the cook chamber. Perfect fit. The air intakes are critical factors to providing the fire with enough air. The holes at the top of the tank should be standard pipe thread so you can buy plugs that will screw on, you just need to find the right size. You could also take your smoker to an auto shop to get a more professional finish if you'd like. When smoking, the bottom damper has to be shut tight and the top damper open. The temperature is set by the rate of burning wood and the excess fresh air is rushing into the pipe together with the smoke. Question My firebox is 30x26x26 It is made of 3/8" steel. The design of this smoker was largely inspired by the smokers used at Franklin Barbecue in Austin, TX considered by many to be the best barbecue in the country. This Instructable will show you how to build the ultimate backyard barbecue pit. Use a flexible tape measure to calculate the length of the curves or just leave the piece long and trim it once it's welded in place. To control combustion and temperatures when cooking, a bottom damper can be adjusted to provide more air which will increase the burning rate and will create more heat and higher temperatures. This calculator is a wonderful resource to use when thinking through your design and deciding on the different dimensions. I'm considering using a 55 gallon drum for my cook chamber, and lining the exterior with ceramic insulation, and wrapping that in a 14 gauge skin. Some smokers come with a temperature gauge to help you monitor the level of heat. 1 year ago No Pipes!. The hole can be drilled in the required area and the pipe can be directly inserted into the hole. The firebox holds the fuel source for smoker and slowly transfers heat over to the main unit. First, you'll likely want to add some thermometers to the cook chamber so you can maintain a consistent temperature. Had a quick question. For the frame I used 2" x 3" tubing because it is very sturdy and easy to weld but you could also use angle iron or C channel. El Cucaracho Smokers, ECS, ECS pits. For the smokestack I'd recommend finding a large steel pipe (5" - 10" in diameter) and leaving it long as you can always cut it down to length once you know how your cooker performs. Get some vegetable oil in a spray bottle or on a clean rag and coat the entire interior of the cooker. It can be welded or threaded and secured with nuts. 1 year ago. 60 Gallon Reverse Flow Smoker Build. For this smoker I used a much larger and taller smokestack than is traditionally recommended in order to maximize airflow through the cooker and ensure a clean burning fire. If you're going to take the time to post all this, why not take it to the next level! Smoker options and pricing. The first step is to cut an opening in the cook chamber. ... Post with 10689 views. I've been looking at 1/2 inch round bar and Schedule 30 3/4 inch tube. The first step is to fill the cook chamber and the firebox with a bunch of charcoal or wood and get it as hot as you can. I had the firebox overhang 11" off of the trailer and placed the axle 31 ½" from the back of the trailer. For the firebox I used 1/4" plate steel but also included 1.5" of ceramic insulation to help retain heat and improve fuel efficiency. I used a simple jig to create a relief bend in the hinges to leave room for the door seal at the top of the door. The cut-out will be your smoker door. Firebox 250 Gallon Propane Tank Smoker. The first step is to mark out where your doors are going to be. Now that the smoker is complete and its got some wheels you're all ready to cook but there are some final finishing touches that you may want to add on to the smoker. Build a Professional Barbecue Smoker: This Instructable will show you how to build the ultimate backyard barbecue pit. Runner Up in the First Time Author Contest 2018. Yes, the rectangular frame of the trailer is 4' x 8' and the tongue extends 36" out from the end of the rectangular frame. Introducing a compact, yet powerful offset, which is the smallest commercial offset smoker we build. Octos 110 Gallon Octo Smoker. Even if you use the PitCalc you can still get these out of balance. The simplest secondary air delivery system is just a covered hole located near the upper part of the baffle. Now that you've got your hinges ready you can start to cut out the doors but be sure not to cut out the whole door until you've got your hinges fully welded on. Related products Quick View. 1 year ago. Cut a 4-foot by 2-foot rectangle out of a flat side on the oil tank. The rate of combustion is independent of the draft and the fire burns as if no chimney existed. However, anything you weld onto the door that you can grab will suffice as a handle. The insulation is not necessary but definitely improves the performance of the smoker. I am planning one within the next year! I too am interested in a 250gal tank smoker. Reply Make sure these supports are parallel to each other and perpendicular to the door so your grates will fit properly. However, the design principles and manufacturing process could be easily applied to any size pit. Next, make the hinges that will slide into the tube by bending some round stock in a vice. Where is the link for the blueprints? Build your own smoker using a heavy duty 11 gauge LavaLock® Fire Box for Offset, Horizontal or Cabinet style cookers. From: $ 4,100.00. You don't have to worry about cutting into the trailer as welding the smoker onto the frame will make up for any structure lost from cutting into the frame. Once you've got your expanded metal welded on you're ready to install the grates. The combustion efficiency inside the fire box depends on the ways fresh air is supplied into the burning wood. You'll want to block up the smoker until you find a height that feels good. I used 1/4" mild steel plate for the firebox and baffle plate and had the steel shop cut it to size for me with their brake. i NEED some dos and don'ts about this idea. Doors have 1-inch x 3/16-inch flat stock around the edges to seal up the pit; no counterweights are needed because they were cut 8" down from the top, dead center, which also cuts down on the weight. ... Like a 250 but way better. Wood rack, grease buckets, and water pan included. In this case the rate of combustion can be easily controlled by adjusting the air supply under the fire. This is one of the tricker parts of the build because of the weird geometry involved between the two shapes but shouldn't be too difficult if you approach it incrementally. There are many different types of hinges you can buy but you can just as easily make your own using some tubing and round stock. A metal box of suitable dimensions can also be used. You'll likely have to do some grinding to get the right fit. The grate significantly increases the efficiency of combustion. The biggest trick here is maneuvering the smoker around in order to get it onto the trailer. I marked a centerline and went a few inches above and below it to get a big enough opening. The ugly drum smoker is about as basic and easy to build as it gets. A highly insulated smoker, like the green egg, ends up working more like an oven than a traditional offset and the meat might not get enough smoke from the convection or may get too much white (dirty) smoke, in the case of the green egg, which causes bitterness in the meat over long cooks. The idea behind secondary combustion is to recover some of the heat that will otherwise go up the chimney by more efficient and cleaner burning of the wood. Did you make this project? I ended up hitting the whole thing with a wire wheel and then painted over it with a high temp paint. Thanks, I have seen several guys doing it and have not gotten or seen an answer anywhere. Incoming air is preheated in a confined but hot area before being divided into two separate streams: the primary (lower) and the secondary (higher). Building a trailer is pretty straightforward and there are several tutorials already online so I won't go into too much detail here but may post another tutorial for building a trailer in the future. I'm having a hard time locating a propane tank large enough, not to mention a professional service that can render it safe to cut open and weld. Going off the advice or Mr. Aaron Franklin (who cooks on big a$$ pits-500 gallon LP tanks usually) I know he typically takes a a 250 gallon LP tank and cuts it in half for his firebox on a 500 gallon LP tank cook chamber. Seasoned in … What size charcoal box should I build? Franklin was something of … First, mark on the tank where you want the opening for the smokestack to be. The book is a highly recommended addition to personal and professional culinary additions. I realize you didn't provide much instruction on the trailer build (your reason is vary valid) but can you provide the dimensions for the trailer? 24x24x24 = 13824 or only 71.8% of what you need. Use a level and soft tape to ensure your lines are straight. If you want to build your own trailer you can buy trailer kits online that include the axle, wheels, springs, hitch, and lights so all you've got to do is weld up a frame. 55 gallon drums can work well for cook chambers but tend to be made of pretty thin metal so I think you're on the right track with insulating the cook chamber. It comes on skids, three style of trailers and a wagon. The raised stool grate type can be an effective tool for switching over from smoking to the cooking process. I found some 1/2 inch schedule 80 pipe that works with the hot rolled 1/2 inch round bar. First you'll want to weld in some angle iron into the cook chamber to support the grates. Small holes 1/8” diameter supplying secondary hot air. Looks awesome! A good method for cutting into a propane tank safely is to fill the entire tank with water and dish soap in order to remove any residual propane and safely cut into the tank. This burns off oil residues. The next step is to measure size of your grates and and cut out your expanded metal and square tubing for the frame. This might be overkill so let me know guys, not sure how much charcoal/wood it takes to keep a 55 gallon drum at 225-250 degrees for extended periods of time. Finding a large piece of steel pipe or a smaller fuel tank is the easiest way to build a firebox but I chose to fabricate my own box so I could insulate it and get the exact size I wanted. ... (or firebox to cook chamber opening) which forces the air mass upward to the top of the cooking chamber where it cooks from the top down. The drawing below depicts a smaller amount of air flowing through the burning wood and the larger portion blows over the wood increasing the rate of burning. I was making one based on the Franklin cook book and your post was very helpful. The easiest way to attack a smokestack is to cut a hole in the top of the cook chamber and weld a pipe to it. Great Build! It is obvious from the drawing that a strong draft has very little influence on a combustion process as the air will only stream faster over the fire. I saw that you put wood on the firebox end of the cooking grate is that to deflect heat? I used a cutting torch but you could also use a cut off wheel for this step. I was wondering about putting the metal floor at the highest point of the firebox so it has to travel all the way across both sides of the meat . All the internal stresses in the steel are released when the door is cut from the rest of the tank and the doors can flatten or distort heavily making fitting them much trickier. 29"x58" cooking surface. I used 14 gauge sheet to save weight and cost. Then you'll cut out pieces to form the rest of the smoke collection. Finally I notched out the back of the trailer and welded the firebox sides directly to the trailer. The three classical ways of placing wood in a fire box follow below: The drawing below shows the most common way of positioning wood when smoking. 250 gallon reverse flow offset cooker. While not entirely necessary, adding trim along the doors helps to keep smoke and heat from leaking out the cracks while you're cooking. I would recommend using at least 3/16" steel for the firebox as anything lighter will loose heat quickly causing you to burn more fuel and will warp and burn out over time. Reverse Smoker Design. Welcome to the pros. This is as easy as welding on a piece of pipe with a valve onto the bottom of the tank. This trailer mounted smoker was built using an old 250 gallon propane tank and is the perfect size large parties, catering, competitions, or whole-hog barbecue. After you've got the tubing tacked in and insulation in place you can complete the firebox by covering the insulated sides with some thinner steel. You also want the opening to be wide enough so that it collects air from the whole width of the smoker and not just the center. This is not needed during the smoking process but may be of use when we start cooking meats. Did you paint over this? (not pictured) The Chudpit 115 gallon offset smoker is the big brother to the 65 gallon and is more robust in every way. The axle placement is the most important part of the build as it determines how much weight you have on the tongue, you want about 10% of your total trailer weight to be on the tongue. In old times the blacksmith was manually pumping more air into the fire to create high temperatures that made metals softer and pliable and that was excactly secondary combustion even though the air he supplied was not pre-heated. This step is necessary for burning off any debris or chemicals that have been left from the tank or the manufacturing process. This smoker is a 87" long by 30" diameter Reverse Flow Smoker with a Square Fire Box on the left side. Our Mounted Double 500 is a show stopper, This double unit is perfect if you’re wanting to run 2 different pits for 2 different temps and cook a whole lot of protein while doing so. Now you'll want to get a nice hot fire going in the firebox and let it cook for several hours. This smoker is a 87" long by 30" diameter Reverse Flow Smoker with a Square Fire Box … You could also add a damper on the the smoke stack or create an airflow valve on the firebox to control the temperature. These types of handles are nice because the tube rotates on the round bars as you lift the door which makes opening the doors much easier. I estimated the center of mass and the total weight of the trailer and did some math to figure the axle placement. It can be an integral part of the smoker or free standing separate unit connected to a smoker by a pipe or digged out trench in the ground. 1. a smokestack that is 6”x 34” 2. Nice work. Yes, you are correct. A fire pit or fire box is the area of the smoker where we burn wood to produce smoke or to generate heat to cook meat products. I would recommend looking for an old utility trailer to mount it on but I decided to build my own trailer because I couldn't find one that quite suited my needs. Maybe look for a larger piece of pipe or get some plate that you could weld into a box. How did you determine the throat size (hole from firebox to cooking chamber). Thank you in advance! The easiest way to build a cooking surface would be to weld a piece of expanded metal directly to some supports in the tank but making your grates removable makes cleaning much easier and you'll thank yourself later. I was able to easily bend the round stock in a vice using a piece of tube to increase the the bending force but you could also use a torch to heat the material and make the bending easier. The angle of that triangle is determined by the manufactured coupler. Rule of thumb. That would be totally possible, you just would want to make sure that the volume ratio between the firebox and cook chamber is right. You may also want to add a grease drain somewhere in the bottom of the cook chamber with a valve so you can make clean up easier. Grate made of metal pipe 1/2”-1” diameter. Sandblast? I have another question. Smoking can be easily done with an open fire (hearth-bottom grate) and adding more sawdust to kindling fire allows for some control at least in respect to smoke. I also chose to insulate my firebox with a layer of ceramic insulation of the top and sides to help with heat retention and fuel efficiency. A metal barrel of smaller size can be used for a fire pit or a large 55 gal (200 l) barrel can be cut in half and imbedded in the ground. Yours seems shorter and fatter. This first major design choice you must make when building a smoker is what you're going to make the cooking chamber out of. If proper rules for efficient combustion are observed the wood becomes a very clean fuel. A baffle can be placed vertically and it will direct heat in a different direction now. Once you've got the doors mostly cut out you're ready to weld on your hinges. I am nearing the finish line and did my big burn. I built the door for the firebox using the same method as I did for the cook chamber doors. When you finish you can scrub the smoker with detergent and scouring … Now that you've got a finished smoker you'll need to get some wheels on it. Text show contact info if … It does look great natural and if you want to keep that look I would recommend hitting it with one of those paint removal wheels for an angle grinder or just some scotch brite to try and remove the chalky substance. Once you've determined the height you can weld some supports onto the trailer to accept the smoker. I marked a line half way down the tank at the same width as the firebox. Once you got a good fit you can weld the firebox on along the edges around the tank. Equipment for Making Alcohol Type Beverages, Directly on the ground, known as the hearth botom-grate, Above the ground on a grate, known as a stool-grate, Above the ground on a grate, known as a raised stool-grate. on Introduction. 250 gallon propane tank!!!!! The ceramic insulation works very well and I don't think I would want anything that insulated the firebox more than that. There are any number of ways to design and build a BBQ Smoker. I'd recommend buying Tel-Tru thermometers or another high quality brand. The deeper the hole the better the draft will be. The first thing you need to do is source your drum. on Step 14. With a 24”x 60” cook chamber made out of 3/8” thick steel, this beast holds heat for hours! Secondary combustion means adding pre-heated fresh air above the burning wood which will add fresh oxygen into the flames and the temperature will rise allowing cleaner and more efficient combustion. Seems like most of the 250 gallon tanks around me are 90+"long and about 30" diameter. Grind the sharp edges off the cut-out. Propane Smoker Grill Smoker Cooker Bbq Pit Smoker Fire Pit Grill Barbecue Smoker Propane Smokers Fire Pits Grilling Custom Bbq Grills. These are just guidelines based on years building smokers but your mileage may vary! Thanks. Now you want to season the cooker in order to get it ready for cooking. The air for secondary combustion is delivered in a higher part of the fire box, just before smoke enters the flue. Baffle plates should be made of a thicker material. Answer Was planning on doing a linseed oil cure and keeping the rustic look. For this build I used an old 250 gallon propane tank because they're made of thick 1/4" steel and relatively easy to find but any other kind of steel tank or pipe will work just fine. Would like to here from you guys. They can be expensive but are very accurate and consistent. You can use a piece of cardboard as a template to get the shape to match the curvature of the cook chamber and the pipe. Measurements and blueprints would be great for us interested. Placing wood on a grate permits the introduction of primary air below the burning wood and better combustion. Making headway on my 72 gallon propane tank reverse flow smoker. Now that you've got the main chamber complete it's time to build the firebox. The smoker itself is pretty big, being 64” long, 34” wide, 66” tall and around 450 pounds. Simply slide the L shaped round bar pieces into the tube and weld them onto the door. Anything deeper than 3 ft will make it impractical to clean up the ashes. Question This is a complete, ready to use firebox, simply Weld on or Bolt on to your homemade cooker, tank, drum or modify to fit your existing cooker.. Let it burn for a few hours and thoroughly clean out any debris. Once you've got your opening marked you can cut it out with the angle grinder. I bent two more pieces of round stock and fit a tube in between them in order to make handles. Call us to find out why! Particularly on the bottom and top of the firebox which are exposed to the most direct heat and can burn out over time when thinner steel is used. The biggest challenge with building a trailer is getting everything square and straight so that the trailer tracks straight when driving with it. It has a gas assisted fire box, which enables you to get your fire started quickly or use the firebox as an oven. It’s a popular model with 784 square inches of cooking space, and a … The less clearance between the top of the baffle, the more heat will be supplied to the top of the fire box. The biggest size, the 24x48x22, is best for those cooking for a larger party or even those that are doing competitive barbecuing. .250" firebox, glow in the dark tell tru guages, 15 gallon waterbox and 1.5" drain. Something like this: https://www.homedepot.com/p/Mueller-Global-1-in-Black-Malleable-Iron-Plug-521-805HN/100165402You could also just cut around the holes and weld a piece of plate in to seal the hole. My smoker was going to have a round firebox simply becasue I got this half a tank for cheap and didn’t want to spend $400+ for … Reverse flow baffle is tapered and drains all grease to waterbox to avoid fires and smoldering grease. Quick View. Question You want your firebox to be roughly ⅓ of the volume of your main cook chamber and should preferably be made of ¼" steel. If you're making your own hinges you can cut some tubing and round stock to length using an angle grinder and a cut off wheel or a metal cutting chop saw if you have one. After welding the top edge you can put in the insulation and weld on the cover sheet to complete the firebox. The next step is to make the cooking grates. I think barrels are only 20 or 22 gauge thick. The general rule of thumb for a horizontal smoker is that the firebox should be 1/3 the size (volume) of the cooking chamber. For these cooking grates I used expanded steel (#9 thickness and ¾" opening size), ¾" x ⅛" angle iron, and ¾" square tubing. The tank is five feet wide, with two rounded sides and two flat sides. I shoot for a number between 103% and 110% with 107% being the sweet spot for the firebox volume. Grind? Depending whether a grate is employed a pipe can be connected to the baffle on the bottom of a fire box or can run over the grate. No mention of measurements,size of the doors,gap measurements, smoke stack size, As the overall execution is clear. Our 288 gallon offset smoker is built in the traditional Texas style, with upper and lower racks on casters or skids. I place the firebox here so that the hot air and smoke enters the cook chamber right at the grate level and travels straight across the tank to the stack opening. 7-ft, 250-gallon tank, 1/4 inch thick steel, 28 inches in height. You want just enough insulation that you can be efficient with you fuel but not so much that you're under-smoking your meat by not being able to add enough wood. All smokers employ a very simple system of draft control as the the main purpose of smoking is to create smoke at low temperatures and that can be often accomplished without any draft system. Carter, Love this post. Once your firebox information is entered, you will see recommended volumes for the chimney, the air intakes, and the throat. 1 year ago Yeah I had the similar chalky residue left over and I assume it’s just burnt primer. I find the part of the cook chamber right next to the firebox gets pretty hot and also gets a lot of direct radiant heat which can easily over cook the meat. It does not wipe off very easily, I have not tried removing yet becuase I like the look, but have a feeling it will need to be sanded off. Be sure not to but the edges completely together so that you have a gap you can fill in with your welds in order to achieve a stronger joint. Next you'll want to cut a notch into your pipe that is the same height as your opening. The hole should be 18 – 24” wide, the bigger diameter the more wood can be burned inside and more heat will be produced, which may be needed when cooking at low outside temperatures. There will be less soot and other unburned particles and less smoke as well. Secondary combustion can be employed in any of the fire pit arrangements as long as there is a baffle and secondary air coming close to the flue as shown in the following drawing. Raised stool grate stove a baffle and the secondary air. This trailer mounted smoker was built using an old 250 gallon propane tank and is the perfect size large parties, catering, competitions, or whole-hog barbecue. That’s great! Note: bluish flames indicate complete combustion. For this project that turned out to be 31" from the back of the trailer but if you want more information on how to calculate the axle placement let me know and I'll post a tutorial. I had a 250 gallon propane tank and decided, using the spreedsheet, that I wanted a little larger firebox than was required. IMPORTANT: Cutting into a propane tank can be very dangerous if not done safely so I'd recommend having a professional clean and cut the tank for your if you're not comfortable doing so. Now that you've got the smoker mostly completed you need to do a burnout and season your cooker. What do you do with the holes at the top of the tank? I will shoot a final when I finish. A fire pit can be a 2 - 3 ft deep hole in the ground, it can be round, square, rectangular, whatever, but it has to be covered with a sheet of metal. This is a welcome scenario as this fresh air brings moisture with it into the smoker preventing the drying out of sausage casings. For my firebox, I'm considering a 1/4" steel for the roof and door, but 14 gauge on the 3 sides and bottom, with firebricks on the inside bottom. Start to finish build of a replacement firebox for smoker. While drawing and designing firebox decided to add a small grill and lid to cook steaks or grill veggies or fish. You can get this paint at most hardware stores in rattle cans. Share it with us! Here the coal bed physically separates fresh air below from the warm air above, a natural draft is created and all air has to flow through burning coals or wood. It can be used for restaurant operations, catering and pop-ups, etc. Of special interest is a collection of 200 recipes which were chosen for their originality and historical value. I got the smaller tank and started making plans for the firebox of the smoker. It is much harder to make a stack taller than it is to shorten one. Now that you've got your doors finished it's time to start on the smokestack. The above drawing depicts a very clever solution where the baffle acts as a pre-heat air delivery vehicle.