We have helped restore a junky very small old house on our hunting land we just leased. I have one side of the room (it's all open) that I'm going to hang my hammock in. The span is 16'. To create some anchor points I'm going to run a 4"x6" up each wall. That's what I'll screw my ring into. I'm only going to lightly anchor the 4x6 to the wall so I need to take care of the tension that will be created when I get into the hammock and the 4x6's will attempt to be pulled towards each other, away from the wall.

The solution is to run a pipe, 2x4, 2x6, etc. along the very top and anchor them to the 4x6's. I want a solution that will last, won't sag over time, and is cheap as possible. The span will actually only 15'4" (just a tad less, actually) once the 4x6's are factored in so I'm wondering if a 2x4 will sag, even if I put it on "edge". The 2x6 (like a floor joist) would do fine as would a gas pipe. Would a fence post that long work without sagging? Something bending and snapping would result in a bad experience.

Thoughts? Hate mail?