Step 8: About paracord
This isn't really a step; more like a justification of my methods. I've read a lot of forums where people say that paracord should NOT be used in this fashion. While I understand the concern, I also know that I've been using paracord on my hammocks for 2+ years now and I've never had a cord break on me yet. It's an acceptable risk to me, as falling may result in a bruise and nothing more.
*Edit -- If you look at the comments, I had an engineer explain the actual physics behind line tension (thanks, dchall8!), so this section isn't exactly right. I still stand by my design because I know it works for me, but my math doesn't quite add up (I majored in Humanities in college).*
Let's do a little math about paracord. I'm an English teacher, not an engineer, so my calculations may be flawed, but here are my methods. The breaking strength of 550 cord is 550 lbs. The common wisdom is that the safe working load is 1/3 to 1/5 of the break strength, which brings the more conservative estimate to 110 lbs safe working load.
Then we need to factor in the knots. Knots can weaken a rope by 50% (although the figure 8 and double fisherman both are generally considered stronger than this), so let's put the 110 lbs down to 55 lbs. But then, there are 4 strands, so we multiply the 55 lbs by 4 to get 220 lbs. So according to my calculations, my hammock should be able to hold a static 220 lbs without fear of breaking. If you weigh more than this, expect to do a lot of jumping while inside, or plan on putting 2 people in your hammock, you may want to use stronger climbing rope. But this system works fine for me.