Hmm... well, for some reason this first pic turned sideways when I uploaded it. I'm not sure what that's about. Anyway, this one shows the holes I cut in the Rubbermaid bin for air and drainage. There are three long, skinny air holes along the tops of both long sides of the bin. And there is one square-ish hole cut more or less in the center of the bottom for drainage and to allow the worms to migrate from one bin to the next when the bins are stacked.
This next picture is of the package of meshy stuff I used to cover the air holes. I wanted something that would permit good air-flow, but inhibit bug infiltration. I am sooo not a big fan of fruit flies! I have read that some people either freeze their scraps or microwave them before adding them to the worm bin in an effort to prevent fruit flies (by killing any eggs laid on the scraps). The "worm food" I've been saving the last few days went into the freezer. Anyway, this meshy stuff is actually replacement filter material for window air conditioners. It is washable, so if it gets gross I can clean it and re-use it. I read Encyclopedia Hydroponica's blog entry about the modifications he made to his worm bin. He used nylon pantyhose to cover the air holes on his bin. I worried that nylons would be too fine for good air flow and would possibly grow mold from the humidity of the bin. So I went with this air conditioner filter stuff. I'll let you know how it works out.
This next pic shows the section of hardware cloth I cut and set in the bottom of the bin. It serves a couple purposes. It helps distribute the weight over the whole bottom after I cut that hole in the middle. It also allows the worms to pass through into the next bin, while supporting and retaining the materials accumulated in the bin. The bottom hole looks dark because it is covered, on the exterior, by a piece of the air conditioner filter. That should keep the worms from exiting prematurely and also deter bug infiltration. But back to the hardware cloth- this picture doesn't show it, but because the edges were sharp, I melted a little paraffin wax to coat the edges. Don't want my wormies getting torn up! For the second bin I will probably coat the entire piece of hardware cloth. But this time I was racing the clock...
Here you see the exterior view of my duct taping handiwork. Okay, it may not win any beauty contests; but if it keeps fruit flies out, I think it's a shoo-in for Miss Congeniality. You can sort of get an idea of how much air this filter material allows through by the amount of back-light you can see through the air holes. I tried to get a close-up of the filter material, but my camera just did not want to focus on it.
This is just an exterior bottom view. You can see a hint of the hardware cloth through the mesh. Nothing too exciting. I tried to get a picture of the worm pile after I put it in the bin. None of those shots really turned out.
And last, but certainly not least, here is a shot of the finished set-up. I have the bin resting on a couple of broad landscape pavers that rest on an upturned bin lid. There is room underneath for me to place a shallow tray to catch any drippings from the bin without having to pull apart two bins like you often see with these Rubbermaid bin systems. This is all an experiment. I haven't cut the second bin yet bacause I want to wait to see how this set-up works out. If I need to make adjustments, I will.