My nephew and I built a compost bin a couple of weeks ago. We built it using big, heavy, wooden pallets. We had to do this in such a way that we could easily remove the top for adding materials, as well as the front for when we are ready to harvest the compost.
Keep in mind that, there are dozens of cats in our trailer park, and we have to keep a top on it so that it does not end up being the local litter box. If this was not an issue, it simply would have been a three sided bin with no top.
So, we nailed the back to the sides at the top, but then could not get nails in on the bottoms. To remedy this, I tied old phone cord around them, to keep them together.
Now, so that we could easily remove the front for harvesting the compost, I simply attached the front pallet to the sides using some black sturdy tape. It will come off easily when I need it to, and then I can set it up with tape again, or maybe wire.
The top is simply a pallet placed on top. It can be removed any time.
So, I shoveled a bag of compost in, dried leaves, then grass. I also put in some not so good produce and some stale bread. Then a layer of dirt, leaves, grass, dirt, leaves, grass, compost, leaves, and more grass clippings. After a few days, I mixed this all up. I have added more kitchen refuse, leaves and grass clippings, and I go out and poke at it with an old broom handles every couple of days.
So far, so good.