Introduction: Sew What Hammock
Hammocks are great fun. When out hiking or backpacking, it's a great feeling to take a quick nap suspended in air above the sharp rocks, on a steep slope, or even over a stream (yes, I've done all these). Plus, they're an excellent way to relax on a lazy summer day in your backyard.
But hammocks either cost money or take time and effort to make. There are a number of solutions to this problem – here's one possible method. This design can be done in an hour for around $10. This would make a great scouting project. If you want a compact, easy-to-build, cheap design, then read on.
And don't forget to vote for me in the paracord contest!
Step 1: Materials
The following materials should be readily available in your local community.
1 piece of fabric, 9 feet in length. You can either buy it at your local Wally-World (look at the bargain material at $1.50 a yard) or you can use a bedsheet. Fabric strength is not really an issue, so pick whatever material you like best, provided it's at least 48” in width (60” pieces are more comfortable). I prefer non-stretchy fabric, but feel free to experiment.
2 carabiners. I found these at my local Home Depot at a dollar apiece. They say they are rated for 150 lbs. While I wouldn't trust them with my life, they hold up just fine for suspending me a few feet off the ground. If you'd prefer something beefier, try stainless steel quick links. They weigh more, but are rated to much higher safe working loads.
35-45 feet of paracord. I know I'm going to get some flak for this one, but in my experience this stuff is strong enough for the way I use it. If you don't feel comfortable trusting your weight to 550 cord, climbing rope can be substituted.
Additionally, you'll need a pair of scissors or knife, and a lighter (optional).
Step 2: Cut the Paracord
From your paracord, cut two 30-inch sections, and divide the rest in half. You should have two pieces 30 inches each, and two that are around 15-20 feet each. If you live in an area with big trees, go for the longer lengths. If you're around small trees (like I am), 15 foot sections will be fine. Seal the ends of all pieces with a lighter or candle. Sealing the ends isn't absolutely necessary, but it will keep the ends from fraying and make things more tidy.
Step 3: Tie the Loops
Tie the four cords into loops. Use a Double Fisherman's bend for a nice strong design (see pictures).
When you're done, you should have two short loops and two long loops.
Step 4: Attach the Cord to the Hammock
Gather one end of your material, and tie a Hammock bend with one of your short loops. The Hammock bend is just an upside-down Hedden knot, which is a relative to the Prussik knot. The climbing guides say to never tie this knot upside down, as it will seize the rope (or in this case, the material), but that's exactly what we're hoping it will do. Clip the carabiner through the loop. Repeat this on the other end of the material with the other short loop.
Step 5: Tie Your Tree Huggers
Starting with the knot end of one of the long cords, tie a figure 8 knot about 9 inches from the end. Tie another one 9 inches from that, and keep going with the entire cord. Repeat with the other cord. My 15 foot length of cord ended up 6 feet after looping it and tying the knots.
Step 6: Setup
This is the easy part. Find two trees between 10 and 15 feet apart. Wrap one of the long cords around the tree, and pull the cord through the end loop (you can start from the knotted end or the other end). Do the same with the other tree. Then simply clip the biners above any figure 8 knot on both cords, and you're done!
Step 7: Getting In
Get in carefully the first time to allow the knots to settle. The hammock bend should should cinch down tight and seize the material, and the figure 8 knots should tighten into their final form. There may be some jolting as everything settles for the first time, but nothing to be alarmed about. Once you feel secure, lay back and relax and have a nice time hanging!
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.
Step 9: About Possible Tree Damage
One more disclaimer: I don't usually use these cords by themselves, as they can cause damage to the bark on the trees as they cinch down. You can either use some extra material to pad the trees, or use Tree Huggers. When tying to posts or other nonliving anchors, this isn't necessary.