Step 1 - Fillet your Salmon. I'd prefer to buy the whole fish from somewhere you trust has a good reputation. Pin bone before salting.
Step 2 - Cover both Salmon fillets in a 3:1 ratio of salt and brown sugar. I used 3 cups salt and 1 cup sugar on this occasion. You want to take caution not to over salt the thinner parts of the fish. Wrap in cling film and place in the fridge for 12 hours. Put a tray or chopping board on the Salmon to weigh it down. I'd put in a large plate but didn't have one big enough. Alfoil was used instead.
Step 3 - Take out of the fridge and wash well under cold running water. Let soak in water for 20 minutes. Lightly glaze in maple syrup to stop the curing process. This is not for taste.
Step 4 - Put in the fridge for 24 hours at 2-4 degrees. I used a spare fridge so the temperature didn't fluctuate with the door opening and closing.
Step 5 - Light your wood. I used Beech wood as it's light flavored and delicate. The last thing you want to use is something rich like Hickory. I like to use pellets and have a maze to put them in. This allows it to burn for 12 hours.
Step 6 - Place the maze inside the oil drum
Good idea to do this on a cold night in winter. You don't want the temperature above 20 degrees Celsius/
Step 7 - Put Salmon on a tray and close lid.
Step 8 - Open lid and refrigerate the Salmon uncovered at 2-4 degrees for 24 hours
Step 9 - Take inside and slice
Step 10 - Eat