Oil Drum BBQ
Inspired by other barrel BBQs shown on here I decided to build one myself. I looked at lots of designs by trawling the internet, and decided that I would incorporate a suspended ash can so the underside of the BBQ would not get burning hot, and it would be easier to empty when cold than by tipping up the whole BBQ. Storage when not in use is also an issue so I wanted the top half to be removable. So I started with a 50 gallon cooking oil drum bought for £10 locally via eBay, and cut it into two equal sized halves with my angle grinder fitted with a cutting disc. That, plus an electric drill were the only power tools needed, and no welding!
Making the Base Unit
As I wanted to form a chimney in the top half around the bung-hole, I used the other half to form the base.
I planned to use a dismantled warehouse shelving system with perforated angleiron uprights, and very thin gauge metal shelves, which would give me the strengthening edges of the base from the angleiron, and the ashcan would be made from one of the shelves. I placed the angleiron along the inside edge of the front and back edges of the base facing inwards, to narrow the cooking area. The narrow angleiron along the two short sides of the base would face outwards to form a shelf that the legs would butt up to. I drilled the fixing holes along the four sides and used the shelving system bolts and nuts to secure them.
I bought a length of half-inch angle iron to make the side strengtheners and legs, which would be bolted to the sides through the strengthening ribs just fitted, and bolted at the bottom of the base side at an angle to form a flat-top A shape. Now I needed to make the fixings for the grids, and work out how to suspend the ash can.
Fixing the Grids and the Ash Can Platform
Two lengths of M6 threaded rod were bought and the holes nearest the edge of the back and front enlarged to allow them to pass through the sides. Pairs of nuts were threaded on and locked together with the excess sticking out to the left. The rods would be used to suspend the ash can platform, and support the three grids which would be used for grilling. Three Ikea trivets measuring 50cm x 17cm (approx 20" x 7") fitted neatly when extra pairs of nuts plus washers were adjusted to keep the grids apart but snugly fitting. The overhang to the left serves as hangers for the BBQ tongs, poker, etc. I had a broken Ikea trivet I had kept in my metal junk bin (which served as a template in the planning stages) and this was cut down to form a shelf on top of the hanger rods to the left.
To suspend the ash can platform I made four 'S' hooks out of scrap fencing wire which fit over the rods and through the fixing holes already in the four corners of the tray from when it was used as part of the old shelving. This although a bit crude did allow me to experiment with height and types of fuel (charcoal or different types of wood) during testing to determine the optimum setting (I'm still experimenting...). Sitting on top of the platform are three old roasting tins I obtained from charity shops, and it is in each of these that the fuel is burned. By using three I can have a small, medium or full-sized BBQ depending on how many are being catered for, and what food is being cooked. One of them is used for fish or vegetarian food when we have guests who would not want their food to be cooked on grids that are also being used to cook meat.
Making the Lid and Chimney
To strengthen the lid I used some light alloy channel I had in my metal bin. I think they are used to fix plasterboard but I could be wrong, anyway, they are squared-off 'U' section and are pop-riveted to the sides. The back edge has French hinges fitted, bolted to the top of the rear edge of the base and the back edge of the lid. I haven't done a very good job of it so will probably strengthen the back edge of the lid and refit the hinges to this. My excuse was that we had invited four couples to a BBQ lunch later in the week and I was running out of time!
Why French hinges? So I can quickly remove the lid for storage purposes, as French hinges have open pintles so each hinge can be fixed to a door jamb and the door lifted off and on without any dismantling. Also I was in France when I built it so it was easy to get them.
The chimney was salvaged from a display stand being thrown out in an office clearance (I had cut off the tilted top which had a leaflet stand attached to it as what I had needed was the base unit which I had attached to a scrap stainless steel washing machine drum to make a fire pit for my patio). The angled bit was kept in my metal bin in case it should be useful one day - and now it was retrieved and bolted to the BBQ lid over the bung-hole. A short length of pipe is added when needed to direct the smoke away from the cook.
With the lid assembled I used two metal Ikea curtain pole holders bolted from the inside of the front of the lid, to hold a wooden pole which is a naturally insulated lifting handle. To stop the lid falling back too far I fitted a short length of chain from one of the chimney bolts and fixed the other end to the end of one of the threaded rods.
To Finish the Job
I haven't finished it properly yet. As explained earlier, the hinges need to be re-done with some strengthening of the front and back edges of the lid to stop it warping, and the whole thing could do with being painted with heat-proof paint. The 'S' hooks should be replaced with something a bit less bodgy-looking, such as flat strip steel hooks properly fixed to the ashcan platform to make it more solid. Anyway, it works as well as I'd hoped it would, my guests were delighted, and I hope you've enjoyed reading about my first Instructible.
Later Modifications
As most of my cooking is for two to four people at a time I only use the centre ashcan and grid. I got an old stainless steel twin drainer sink left over from another project and cut one draining board off and then split it in two using my trusty angle grinder with metal cutting disc. After carefully cleaning up all edges with a file, and bashing the sides flat the two halves just covered the unused grids either side of the centre grid. They make handy tables for keeping things hot whilst the last item is being grilled, and are easily cleaned down at the end.
Second modification is to attach a drop-down two stage prop to the lid handle, so I can keep the lid open a couple of inches or about six inches. This helps to regulate airflow and temperature.
Third modification occurred after a summer rainstorm when there was about three inches of water in the bottom of the lower half, despite the lid being shut! I punched a drain hole in each of the drum ribs in the lower half and the water ran off.
Cooking with the lid on means a lot of the heat is retained, about 200 - 300 degrees F, so food steams as it is being grilled, resulting in fully cooked food which doesn't need to be cindered on one side to be ure it's done! I'm learning more each time I use it, the last experiment was to cook a whole small chicken by pushing the charcoal away from the centre so the fat dripped onto the bottom of the ashcan and didn't flare as it would if it dropped onto hot charcoal. The chicken cooked as if it were in a conventional oven, from the reflected heat and not from direct flames. I browned it at the end from pushing the charcoals into the centre, igniting the fat which I then allowed to burn off with the lid off and the bird resting on the side on a serving dish.
Thanks everyone who has looked at this project, if you make one I hope it gives you as much fun and good food as I am getting out of it.