A cheap sieve from a bargain shop, cut the handle off and push the middle in. It create a ring around the edge, fill with pellets or wood chips and light, mine smoulders foe around 7 hours.
For your garden sieve, just put a terracotta plant pot upside down in the middle. Then pour wood dust around the sides and you have a ring of sawdust that will burn for about 12 hours.
Had the thing for about a year already and still not managed to use it. Must try and use it now that winter is here and it should be nice and cool for the food.
I'm thinking of making a metal spiral to lay inside ao that it burns for ages... Good idea re. The pot though.
It keeps it simple! Plus, it's actually good for food to have a rest from smoke so if you wanted a longer smoke, you could do 12 hours on, 12 hours off, 12 hours on again etc.