Aviation Trolley Barbecue Smoker With a Twist

For some odd reason I’ve always been interested in repurposing items in a way they were never intended. This time I wanted another smoker and the donor object for it had to be an old (half sized) cabin trolley. One of those that the flight attendants walk around with during the flight when serving drinks and snacks or cleaning up your mess. These trolley carts show up on second hand sites every now and then, prices vary a lot and the slightly damaged ones typically go cheaper. Since this project replaces the walls a few dents aren’t an issue.

What makes this smoker special is the option to heat liquids in it that are accessible without opening the smoker and thus losing heat. Their thermal mass even assists in keeping an even temperature during the smoke. I’ve used it for soup and sauces but the containers can also be used to keep your cooked items warm while serving, a built in “au bain marie”.

Materials required:

• Flight Trolley
• Aluminum L profiles
• Aluminum sheets
• Pop rivets
• Mesh or expanded metal or grill rack
• Gastro Norm bins (various sizes) with lids
• Thermometer
• Piano hinge
• Door latches
• Ceramic stones (optional)

Tools required:

• Screwdrivers
• Hacksaw / Angle grinder with cut-off discs
• Drill
• Step drill
• Pop rivet gun
• Drill bit for pop rivet
• Hammer / mallet
• Pliers

For its original purpose the Airline service trolley obviously had to meet aviation quality standards which means that these devices are made of light weight parts that are expected to have a rough life and are thus designed to be repaired. It just takes a few screwdrivers to strip the cart down to its individual components. Depending on the life it has led a wrench or rubber mallet might come in handy to persuade some of the items to come apart after the fasteners have been removed.

The flight trolley (I assume that by now you figured out that I’m using all the names I can find for the thing so I can make sure that I at least used the correct one somewhere in the instructable) is basically a frame made of extruded aluminum held together by screws. It has a swing door on the front and sometimes a lid on the top. The larger (full size) catering trolleys will have doors at both sides. The sides and door(s) are aluminum sandwich panels that fit snugly into the aluminum frame.

In my trolley the sandwich panels consisted of 2 aluminum sheets glued to some type of foam. As I planned to turn this into a barbecue and light a small fire on the inside of the cart this didn’t seem to be the best material for the job. The heat will affect the consistency of the foam and probably also add some unhealthy flavor to my meals. I therefore decided to remove the sandwich panels and replace each with 2 separate sheets of aluminum. To clamp the 2 sheets in place and make it all fit snugly (while capturing some air for insulation at the same time) I simply wedged some aluminum strip between the sheets. The thickness of the strip depends on the aluminum extrusion and the thickness of the sheets. In my case the aluminum extrusions were made to host 8mm thick panels (or for those of you that prefer a measurement system based on the length of medieval European body parts: that’s roughly 5/16 inch). My 2 aluminum sheets are 1.5mm so I had to use a 5mm strip to fill the gap.

The back of the trolley cart is single walled aluminum which could have theoretically be reused but I decided to replace anyway for the looks.

The common method for controlling the temperature in a vertical smoker is by regulating the airflow, for that to work the device has to be more or less airtight which was the most challenging part.

The hinges of the original door had quite some wear. Instead of trying to repair/remake them (which would be required to seal the door to a level that the temperature of the smoker can be managed by airflow) I decided to create a double door. The extra (inside) door covers approximately 80% of the height which leaves room for a shelve at the bottom. The extra door is single walled aluminum checker plate (no technical reason, just because I like the looks of it) and rests against L profiles. It uses a piano hinge on one side and a few simple door latches on other. The same type of L profile is used to place the shelves on. All these added parts are connected using pop rivets. A hole in the middle that allows for a thermometer completes the door.

The latches and hinge create a seal that is good enough to control the temperature inside the smoker. I considered adding felt (as used in a ceramic smoker) but it proved unnecessary.

The outside door remains open during use to ensure that the bottom shelve of the trolley where I keep my barbecue controller doesn’t get too hot. (the controller is a heater meter; that device is not part of this instructable as it is an optional component and the smoker can be controlled manually. For those of you interested: someone else created a instructable on it here)

I assume that some of the readers by now question my sanity after realizing that I decided to make an aluminum barbecue. Thanks for your concerns but rest assured: I am aware that the material has a relatively low melting point and decided that for me this wouldn’t be an issue. The part closest to the fire, the firebox, is made of stainless steel (more on that later) and in the end it’s a smoker not a grill; my preferred smoking temperature is 110 Celsius (225F) and even if I decide to go a little hotter near the end of the smoke to build up some bark it’ll never be more than 180C (or 360F) which is way below the point of critical failure of the aluminum.

In order to regulate the temperature, a vent is required near the top for the hot air and smoke to escape and one near the bottom to allow oxygen in. The one at the top I created from a piece of L profile and a strip that slides on it. Both have the same hole pattern drilled into them (keep as much or slightly more room between the holes than the diameter of the hole so you can close it entirely, a step drill is a perfect tool for the job), the strip needs to be at least the diameter of the hole smaller than the profile and requires a little knob to open and close it.

The lower vent is nothing more than a wide strip of aluminum that pivots near the rear wall and closes a hole in the bottom.

Oxygen is required for the coals to burn, the air surrounding the coals heats up and rises. By allowing the hot air to leave the smoker at the top, cold air is sucked in at the bottom to fill the “gap” caused by the escaping air which results in air circulation. I used a Gastronorm (also known as Gastro-Norm) bin as fire box. These gastro norm bins come in various sizes and one of them fits nearly perfect. By drilling holes in the sides of the bin (I highly recommend using a step drill to create the holes in this thin sheet metal) and placing some wire mesh on the bottom of the bin I ensured that the only way for the air to travel from the bottom to the top of the smoker is around the coals.

For grates you can of course go shopping in the cooking supply area of your favorite store, you will probably need a hacksaw or angle grinder to make them fit. I used some stainless-steel mesh that I cut to size. Expanded metal is probably the easiest to get a hold of if you want to make the grates yourself. The grates rest on aluminum L-profiles that I connected to the walls using rivets. I added a extra set of profiles just above the fire box and bought a set of ceramic stones typically used in gas grills. They assist in creating a even temperature around the smoker and their thermal mass also helps heating the chamber up after opening the door during the cook.

The top of the smoker is nothing more than a aluminum sheet with a hole the size of the gastro norm bin. To cut the hole simply place the bin upside down on the sheet, mark the outside of the bin and then use that line to cut a hole a few millimeter smaller such that the bin is able to hang in it. In some of my pictures you'll see 2 smaller bins hanging in it.

I played around a bit adding shelves with gizmos to the smoker trying to figure out what would make sense. I first added a roll of paper but that didn't do it (althoug it looks ok on the pictures). I settled with a small, self supporting, shelve that has some cutouts for my knives and a slightly larger shelve (same size as the top of the cart so that can also lay on top if not attached to the side) supported by a leg. Both shelves are detachable and can be stored inside.

The last step was painting the aluminum walls black and try it out, of course we start with some strips of pork belly for its maiden run. Last few pictures are made during a 10 hour pulled pork session.