Site Navigation

Sunday, April 3, 2011

Double Layer Hammock Pattern



Here is a pattern I have put together to build one of my favorite hammock styles.  It is fairly straightforward if you know how to sew.  I am sure the directions could even be more simplified by an expert.  I am not a DIY expert, I don't pretend to be, just a hobbist.  These instructions have no guarantees of perfection or safety, they are published for your consideration and reference.

Materials needed to build one hammock using these directions:

Quest Outfitters:
  • #1202 NO-SEE-UM MESH , (Black) --------------4yds
  • #2032 GROSGRAIN RIBBON - 1 inch Black------12yds
  • #5030 #5 COIL ZIPPER by the yd BLACK-------- 4yds
  • #5043 #5 COIL NL REV ZIPPER TAB BLACK---2 eaches
  • #2400 1/8 shock cord--------------------------------2yds
ArrowHeadEquipment
  • Polyester Tree Straps-------------------------------- 30ft yields two 14 foot straps with 3 inch loops
  • 7/64th Amsteel -------------------------------------- 25ft
Other Suppliers
  • Ripstop/Taffeta Nylon or Polyester 58 in+ wid-------12yds (8yds for body + 2 12ft x 6in wings). This will leave some leftover to make a hammock stuff sack and a ridgeline organizer.
  • Home Depot Mason Line for Whipping-------------- One Roll
  • REI SMC Decending Rings-------------------------- 4 eaches

Directions:

1. Cut two pieces of fabric (rip stop nylon, nylon or polyester taffeta) for the base layers. Dimensions: 11 feet long by 58+inches wide.

2. Cut two pieces of fabric (rip stop nylon, nylon or polyester taffeta) for the wings. Dimensions: 11 foot long by 9 inches wide

3. Sew a 1/2 inch rolled hem on one side of the inner base layer; see green line in figure below. This will be the finished inner layer that you will see and feel when you enter the hammock.  This hemmed edge will be next to the zipper and the rolled portion of the hem will be down.


4. Attach wings and zipper (if you are building a Black Bird clone,  use the shelf/footbox piece in place of the right wing).


5. Hem ends with a 1 inch channel.  The hem will go across the wings, zipper, grosgain and base layers.  Once hemmed the overall length of the hammock will be about 10’ 6” or 126”.



6. Cut a piece of rope that has a 300lb + working strength for the structural ridgeline of the hammock.  I personally like to use Amsteel or LashIt and use a splicing method to develop an adustable structural ridgline (ASR).  To learn more about how to build an ASR, see the following link:
http://www.whoopieslings.com/

To learn more about structural ridgelines for a hammock see the following:
To the Woods

If you are unfamiliar with splicing then good old fashion knots work well and you can build a static ridgeline very quickly and without much hassle.   To build a knotted static ridgeline,  measure the length of your hemmed hammock (about 10’ 6” or 126”.)  The rule of thumb is  that your finished ridgeline would be about 83% of your overal hammock length, about 100-103”.  Then tie loops into each end of the ridgeline rope, I tend to use a figure-eight knot, since they are easy to undo in case I need to readjust it at a later time. The end product should look like this:


7. Run a piece of small diameter rope (mason line, ZingIt, LashIt) through each of the hemmed end channels and use Knotty’s method in the video below to whip the hammock.  This method is similar to the Warbonnet Black Bird whipping method, and is one of the most comfortable I have used.   The only thing I do different is whip the hammock around the structural ridgline that we created in the previous step. This means that loops we tied into the ridgeline are poking out of the center of the whipped mass when complete.  I think this gives a more finished look and works better with an attached bugnet.  I will try to get a picture of this posted so that it makes more sense. 

The following tutorial was put together by Knotty from HammockForums.net.



Do not tie the knots  in the whipping that you can't undo. Also do not cut the excess of the whipping rope.   We will need to undo this to attach the bugnetting. This is just a dry run to make sure it is comfortable before attaching the bugnet.


8. Attach your favorite suspension to the whipped ends.  This becomes a very subjective area for most people as they all have their favorite type of suspensions.  The one I like the best is the webbing and ring buckles, others perfer to use whoopie slings or a cord variation.  See the following videos on the different types of hammock suspensions.  They can all be purchased or done by DIY methods.

These tutorials were put together by Grizz from Hammockforums.net, check out his other videos to learn more about hammocks.

Webbing:


Cord:


Whoopie Slings (Constriction):


There are vendors that sell the DIY materials and also finished product for the suspension, here are a few that I have used:

Arrow Head Equipment
Backwoods Day Dreamer
Jacks R Better

Once you have attached your suspension,  hang the hammock and try it out. Make sure the lay is comfortable, if not adjust the ridgeline length until you are happy with the lay. Once you have it dialed in, it is time for the bug net.

9. I like to fold my bug netting fabric long ways and then cut out the following basic shape. I know there are a few more complicated ways to determine exact lengths of the cuts, but I have found that the most simple for me is to actually just measure the exact size I need based upon my hung hammock.  The critical points to measure are shown below:


a. Determine where you want the tie-outs on the hammock (line Q end points)**; their purpose is to pull the bug netting away from your face. I like the WBBB method that uses two points instead of just one.  I determine where I want them by laying in the hammock and having someone pull the fabric out away from my face at different points.  Once you know the position of the desired pullouts, then use a right angle to determine where at on the ridgeline the tie out would intersect. Once you have those four points indentified you can quickly measure the distance for the (Z, ZZ, Y, and Q values). Then from there it is as simple as cutting out the basic shape.

** If building a Blackbird clone, you will use the measurements on the shelf to determine where the tie outs would be on each side.

b. Once you have the basic shape cutout, you need to shape the edges of the bugnet by cutting an arc into each side. These arcs are called catenary cuts, they help make the bug net stay uniformly taut.

I do catenary cuts that are 4-5 inches deep at the center on the long side and 2-3 inches deep at the center on the two shorter sides.  To find the center measure the length of the edge you want to shape and divide by two.  Find that point on the edge and measure the depth you want to cut to.

I like to use a long piece of flexible wood to model the curve so that I can mark where to cut on the bugnetting.


10. The last and final step is to attach the bug net onto the wings using the grosgrain ribbon.
  • While the hammock is hanging, pin the bugnet securely onto the hammock, just like it would be when sewn.
  • Remove suspension and undo the whipping so that you can sew all the way to the ends.
  • Start at the tie out points and sew the bugnet directly to the hammock wings, sewing toward the ends. Sewing towards the ends pushes out any of the puckers or excess to the ends where it can be trimmed.
  • After sewing the bugnet directly to the hammock,  finish the edge with one inch grosgain ribbon.
11.  Sew loops using the grosgain to the predetermined points where you want the bugnet/wings pulled away from your face.

12.  Attach cord/bungee cord to the tie outs,  I usually use three foot piece of cord tied between the two tie outs on each side. To this cord I attach a four foot piece of bungee cord.  The bungee piece attaches to the stake.


------------------------------------------------------------
Optional Step to build a WBB Shelf and footbox piece.

Here are the approximate measurements and shape. It is all one piece. If you go this route remember you will use this piece in place of the non zipper side wing.

The red dotted line indicates a second layer of heavy nylon sewn on to serve as a patch to help strengthen the neck between the footbox and shelf. It is critical to put it there as to help absorb the strain.

The finished BlackBird Clone should look something like this:





Good luck,

~C

4 comments:

  1. Whoa. I'm still working on learning how to knit dish clothes. I don't even know how to turn on a sewing machine. Can we pay you to make us two hammocks?

    ReplyDelete
  2. I love the blog. I was told by Steph and Eli to take a look and I am glad that I did. great info. and tips.

    ReplyDelete
  3. Hi there,

    Just wondering, you made and 11ft version, thought your footbox side is only 104inches (8.6ft) which leaves you 2.6ft short. So how does that work out? Cheers.

    Ghillieshot (HF)

    ReplyDelete