A project I started ages ago then didn't complete what with life getting in the way. Working my way through a pile of salvaged joists which I'm cutting into shorter lengths to make a compost bin for all the prunings and "green waste" etc. in my father's garden in Hertfordshire. Will post a photo of the finished product in due course. 

 The minimum size is about a metre square for the composting processes to work effectively. A wooden structure is always the best. Those plastic "Dalek" bins tend to be too wet or too dry, too hot or too cold and difficult to turn over. Or failing that the good old compost heap. Ah, a steaming pile on a cold winter's day- what could be better?

 

 Postscript  What the Americans call chainsaw carpentry albeit with a jigsaw. Some of the timbers are rotten but there will be enough for one bin, possibly two and some outdoor shelves.