The best fly trap is the one that is cheap enough to hang six of. Ours is a printed top that snaps or screws onto a standard 5 gallon pail, so the bucket is the trap body and the part you buy is just the lid. There is a 55 gallon drum version for a feedlot and a 2 liter bottle version for the porch.

Baiting it

Flies come in through the entrance in the lid, go toward the light, and cannot find their way back out. What brings them in is the bait. A couple inches of water in the bottom with a scoop of attractant is the standard. We sell an attractant that is matched to the trap, but a fish scrap or a dead mouse in the water works too, it just smells worse for you as well as the flies.

Where to hang it

Downwind of where the flies are, not where you are. Between the barn and the house is a mistake; you are pulling flies through the yard on the way to the trap. Hang it on the far side of the pens or on the lee side of the barn, in the sun, about chest height. Flies want warmth and light, so a trap in the shade fills slower.

How often to dump it

A well placed trap in fly season fills in about a week. When the water is a solid layer of flies, it stops working, so dump it, rinse it and re-bait. The printed top is PETG and will not go brittle in the sun; the bucket is the part that eventually cracks, and buckets are free.

Printing your own

The STL files for both the snap-in and the screw-together tops are in the store, if you would rather run a dozen off your own printer.